JP2003294687A - Stacked gas sensor element, its manufacturing method, and gas sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stacked gas sensor element capable of starting measurement at an early stage and achieving low power consumption, high resistance to heat, and compactness, and to provide its manufacturing method and a gas sensor. <P>SOLUTION: A first insulating base 11 having a heater 113, a second ion conductive part 13 having a solid electrolyte body 131 and electrodes 132 and 133, a cavity 15, a first ion conductive part 12 having a solid electrolyte body 121 and electrodes 122 and 123, and a second insulating base 16 having a porous part 161 having permeability, are stacked sequentially in this order. Part or the overall side surface of the porous part 161 is surrounded by a non-porous part 162, or the porous part 161 is provided in such a way that air permeates at least in the directions of its side surfaces. At least the end edge of the surface of the porous part 161 that does not face the first insulating base 11 is covered with the non-porous part 162. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated gas sensor element, a method of manufacturing the laminated gas sensor element, and a gas sensor. More specifically, the present invention relates to a laminated gas sensor element having excellent thermal strength and mechanical strength, a method for manufacturing such a laminated gas sensor element, and a gas sensor including such a laminated gas sensor element. INDUSTRIAL APPLICABILITY The laminated gas sensor element and gas sensor of the present invention are suitable as a gas sensor element and a gas sensor used for detecting and measuring gas components in exhaust gas of various internal combustion engines used in automobiles and the like.

[0002]

2. Description of the Related Art Conventionally, for the purpose of protecting an electrode (for example, a detection electrode) formed in the outermost layer of a gas sensor element, a porous portion is generally provided so as to cover the surface of the electrode. (Japanese Patent Laid-Open No. 11-223616, etc.). Such a porous portion can be formed by various methods. For example, it can be formed by spraying spinel on the electrode surface (Japanese Patent Laid-Open No. 9-203717, etc.). Alternatively, a desired portion of the unfired gas sensor element can be formed by immersing a desired portion of the unfired gas sensor element in a paste that is made porous by firing, applying the paste, and then firing (JP-A-9-170999). On the other hand, it is also possible to form a porous portion by sticking an unsintered sheet containing a component to be burned off at a desired position and then firing it because it is simple in the manufacturing process and the like (Japanese Patent Laid-Open No. 2001-2001). 281
No. 207).

[0003]

The porous portion 161 obtained by sticking the above-mentioned unsintered sheet and then sintering it.
Usually has a general shape as shown in FIGS. However, the porous portion is inferior in thermal strength and mechanical strength to the non-porous portion, and it is particularly preferable to protect its end portion if possible. The present invention has been made in view of the above circumstances, and an object thereof is to prevent a decrease in strength at the end of a porous portion, and to provide a laminated gas sensor element having excellent thermal strength and mechanical strength as a whole element. And Further, it is an object of the present invention to provide a manufacturing method capable of reliably and stably obtaining such a laminated gas sensor element. Moreover, it aims at providing the gas sensor provided with such a laminated gas sensor element.

[0004]

A laminated gas sensor element of the present invention comprises a first insulating base portion, an ion conductive portion having a solid electrolyte body and a pair of electrodes formed on the surface of the solid electrolyte body, and A second insulating base portion facing the first insulating base portion and a second insulating base portion are laminated in this order, and the second insulating base portion is provided with a porous portion capable of venting at least in the front-back direction,
Part or all of the side surface of the porous portion is surrounded by the non-porous portion, and only one of the pair of electrodes is in contact with the atmosphere to be measured through the porous portion. It is characterized by being arranged. Further, the entire side surface of the porous portion is surrounded by the non-porous portion, and the width of the frame portion formed of the non-porous portion surrounding the side surface of the porous portion is 0.2 mm or more. be able to. Furthermore,
A recess may be provided on the side of the second insulating base that does not face the first insulating base, and air may be ventilated in the front-back direction of the second insulating base through the recess and the porous portion.

Another laminated gas sensor element of the present invention comprises a first insulating base portion, an ion conductive portion having a solid electrolyte body and a pair of electrodes formed on the surface of the solid electrolyte body, and the first insulating layer. A second insulating base portion facing the base portion and a second insulating base portion are laminated in this order, and the second insulating base portion is provided with a porous portion that allows ventilation in at least a lateral direction, and
A non-porous portion that covers at least an edge of a surface of the porous portion that does not face the first insulating base portion, and only one of the pair of electrodes has the porous portion interposed therebetween. And is arranged so as to come into contact with the atmosphere to be measured.

In the laminated gas sensor element of the present invention and another laminated sensor element of the present invention, the porosity of the porous portion may be 5 to 80%. Furthermore,
A cavity serving as a reference gas introduction chamber or a detection chamber is provided between the first insulating base portion and the ion conductive portion, and faces the second insulating base portion of the cavity in the width direction of the stacked sensor element. The projected image of the outer peripheral line on the side may overlap with the projected image of the outer peripheral line of the porous portion, or may be located inside the projected image of the outer peripheral line of the porous portion. Further, another ion conductive portion is provided between the first insulating base portion and the ion conductive portion, and a cavity serving as a detection chamber is provided between the ion conductive portion and the other ion conductive portion, In the width direction of the laminated sensor element, the projected image of the outer peripheral line of the cavity facing the second insulating base portion overlaps with the projected image of the outer peripheral line of the porous portion, or It may be located inside the projected image of the peripheral line.

A method of manufacturing a laminated gas sensor element according to the present invention comprises a first laminate having an unfired first sheet which becomes the first insulating base, and an unfired second which becomes the second insulating base.
A step of stacking a sheet and a second laminated body having an unsintered ionic conductive part serving as the ionic conductive part and then sintering the stacked product is performed, and the unsintered second sheet is sintered to become the non-porous part. A non-sintered non-porous portion and a non-sintered porous portion that is calcined to become the above-mentioned porous portion are provided, and the non-sintered non-porous portion has a post-shrinkage shrinkage rate of the non-sintered porous portion. Is the same as or larger than. Further, the gas sensor of the present invention is characterized by including the laminated gas sensor element of the present invention and another one of the present invention.

[0008]

EFFECTS OF THE INVENTION According to the laminated gas sensor element of the present invention (including the second insulating base portion in which a part or all of the side surface of the porous portion is surrounded by the non-porous portion), the strength of the porous portion can be improved. It can be effectively supplemented, and the element as a whole has excellent thermal strength and mechanical strength. Further, since the entire side surface of the porous portion is surrounded by the non-porous frame having a width of 0.2 mm or more, it is possible to obtain particularly excellent thermal strength and mechanical strength. Furthermore, by providing the second insulating base portion with a recess and allowing ventilation through the recess, the strength of the porous portion can be effectively supplemented, and the element as a whole has excellent thermal strength and mechanical strength. Will have.
According to another laminated gas sensor element of the present invention (which includes a multi-layered second insulating base portion), the strength of the porous portion can be effectively supplemented, and the element as a whole has excellent thermal strength and mechanical strength. It will have strength.

In these laminated gas sensor elements of the present invention, the porosity of the porous portion is a predetermined value, so that more excellent thermal strength and mechanical strength are exhibited.
Further, a cavity is provided between the first insulating base portion and the solid electrolyte body, and the projected image of the outer peripheral line of this cavity overlaps with or is located inside the projected image of the outer peripheral line of the porous portion, that is, By adopting a mode in which the boundary between the porous portion and the non-porous portion where stress is more likely to be concentrated than other portions is not arranged on the cavity, durability against cracks and cracks is improved, and further, the mechanical properties of the entire device are improved. The physical strength can also be improved. Also,
Another ion conductive portion is provided between the second insulating base portion and the ion conductive portion, and a cavity is provided between the ion conductive portion and the other ion conductive portion, and the projected image of the outer peripheral line of this cavity is porous. Be located on or inside the projected image of the outer line of the quality part,
That is, compared to the other portion, by the mode in which the boundary between the porous portion and the non-porous portion where stress is more likely to be concentrated is not arranged on the cavity, the durability against cracks and cracks is improved, and further,
The mechanical strength of the entire device can be improved.

According to the method of manufacturing a laminated gas sensor element of the present invention, the laminated gas sensor element of the present invention and other laminated gas sensor elements of the present invention can be obtained in a stable and reliable manner. In addition, due to the structure of these laminated gas sensor elements,
It is possible to form an element which is conventionally formed by laminating another portion on an unsintered sheet serving as a first insulating base portion, and is laminated with another portion on an unsintered sheet serving as a second insulating base portion. ,
Greater flexibility in element design. Further, according to the gas sensor of the present invention, high durability can be exhibited.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION [1] Part constituting the element of the present invention and another element of the present invention The laminated gas sensor element of the present invention and the other laminated gas sensor element of the present invention include a first insulating base portion. , An ion conductive part, and a second insulating base part. Hereinafter, these portions and other portions that can be included in the element will be described.

(1) First Insulating Base The above-mentioned "first insulating base" is a second type which will be described later in terms of the strength of the entire laminated gas sensor element (hereinafter also simply referred to as "element").
This is the part that guarantees it together with the insulating base. The shape and size of the first insulating base are not particularly limited, but usually,
The thickness is 0.1 mm or more (preferably 0.2 to 1.5
mm, more preferably 0.5-1.0 mm, usually 2.0
mm or less). If the thickness is less than 0.1 mm, it will be difficult to sufficiently secure the element strength.
When the step of laminating an unfired layer to be another portion is performed on the first insulating base during manufacturing, this lamination may be difficult. Further, the first insulating base portion may be a single-layer body or a multi-layer body.

The first insulative base is made of insulative ceramics and can exhibit a sufficient insulative property. The degree of this insulating property is not particularly limited because it varies depending on the use environment, the size of the element, etc., but for example, at a temperature of 800 ° C., the electric resistance value between a pair of electrodes included in the ion conductive part described later is 1 MΩ (preferably 10 MΩ) It is preferable that the above insulating properties can be exhibited. Examples of the insulating ceramics capable of exhibiting such insulating property include those containing one or more of alumina, mullite, spinel, steatite, aluminum nitride and the like as a main component. . Among these, alumina or insulating ceramics containing alumina as a main component is preferable because it is inexpensive and relatively easy to process.

When using alumina or a material containing alumina as a main component as the insulating ceramics, sufficient insulating properties and heat resistance (heat shock resistance, etc.) are exhibited.
70 mass% or more of alumina (more preferably 80 mass% or more, further preferably 90 mass% or more;
It may be 100% by mass). On the other hand, the remaining part may contain 1 to 20% by mass of a component that constitutes a part (for example, a solid electrolyte body or the like) to be laminated in direct contact with the insulating ceramic part. The remaining part contains a component that constitutes a portion to be laminated in direct contact with the insulating ceramic portion, so that the thermal expansion between the first insulating base portion and the portion to be laminated directly in contact with the first insulating base portion. The difference is eased.

However, when it is necessary for the insulating ceramic portion to exhibit a particularly high insulating property, 90% by mass or more of alumina (more preferably 95% by mass or more, still more preferably 99.99% by mass) relative to the whole is required. Or more) and contains 10000 ppm or less of silica (more preferably 1000 ppm or less, further preferably 50 ppm or less) or does not contain silica (below the measurement limit)
It is preferably one. With such an insulating ceramic, for example, even when the heater is provided on the surface or inside of the base, it is possible to reliably prevent the leakage of current from the heater to the electrode.

(2) Ion Conducting Portion The above "ion conducting portion" comprises a solid electrolyte body and a pair of electrodes, and can move predetermined ions or gas from one electrode side to the other electrode side. It is the part that can be done. This ionic conductive part is, for example, a concentration battery part capable of outputting the concentration of the gas to be measured as a potential difference, or a predetermined ion or gas from one electrode side to the other electrode side by applying a voltage to a pair of electrodes. And the like can function as a pump cell unit or the like that can move the like. The ionic conductive portion may be composed of only the solid electrolyte body and the pair of electrodes, but may further include other portions such as electrodes for measuring the internal resistance of the solid electrolyte body. Further, only one ionic conductive portion may be provided in the element, but two or more ionic conductive portions may be provided in the element. The gas to be measured is a gas that constitutes the atmosphere to be measured, is a gas to be measured by the element of the present invention or another element of the present invention, and is composed of one kind or two or more kinds of components.

(2-1) Solid Electrolyte Body The above “solid electrolyte body” can be used without particular limitation as long as it has ionic conductivity. Examples of the solid electrolyte body include a zirconia-based sintered body (which may contain a stabilizer such as yttria) and LaGa.
An O ₃ based sintered body and the like can be mentioned. Among these, in the case of conducting oxygen ions, it is preferable to use a zirconia-based sintered body (containing yttria or the like as a stabilizer) which is particularly excellent in oxygen ion conductivity. This solid electrolyte body (in the case of including a plurality of ionic conductive portions, means a solid electrolyte body provided in a first ionic conductive portion described later) is the first insulating base portion and / or the second insulating base portion. They may be laminated directly in contact with each other, or indirectly laminated via an electrode or another member.

The shape and size of the solid electrolyte body are not particularly limited. Further, the thickness thereof is not particularly limited, but 300 μm or less (further 200 μm or less, particularly 150 μm).
In particular, it can be 50 μm or less, usually 20 μm or more). In particular, when the solid electrolyte body is thinned to 150 μm or less, the element can be downsized, and the thermal conductivity of the solid electrolyte body, which is usually smaller than that of alumina, can be reduced, and the heat inside the element can be reduced. Since the conductivity is improved and the heat of the heater is easily transferred to the ion conductive portion, the element can be started earlier. Furthermore, various excellent effects can be exhibited, such as the power consumption can be suppressed to a lower level. Even if the solid electrolyte body is thicker than 300 μm, its function as an element is not lost, but it is difficult to obtain the above-mentioned excellent effects. On the other hand, 20μ
When the thickness is less than m, it tends to be difficult to produce and it is difficult to obtain sufficient ionic conductivity.

(2-2) A pair of electrodes The above-mentioned "pair of electrodes" are electrodes formed on the surface of the solid electrolyte body. Only one of the pair of electrodes is an electrode capable of coming into contact with the atmosphere to be measured through a porous part provided in a second insulating base described later (in the case of including a plurality of ion conductive parts, the electrode described below It means one of the electrodes included in one ionic conductive portion). The other of the pair of electrodes is in contact with the atmosphere or a reference gas having a constant pressure and is not in contact with the atmosphere to be measured (when a plurality of ion conductive parts are provided, the first ion conductive part described later is It means one of the electrodes provided). In addition, the pair of electrodes may be arranged so as to face each other by being formed on one surface and the other surface of the solid electrolyte body respectively, and both electrodes should not contact each other on the one surface side of the solid electrolyte body. It may be arranged in.

The shape of each of the pair of electrodes is not particularly limited, but may be composed of, for example, a wide electrode portion and a narrow electrode lead portion. Moreover, the size of these electrodes is not particularly limited.
Furthermore, the material forming the pair of electrodes is not particularly limited, but for example, at least one of platinum, gold, silver, palladium, iridium, ruthenium, and rhodium is the main component (usually 70% by mass of each electrode). Or more), and it is usually preferable to use platinum as the main component.
Moreover, the main component which comprises a solid electrolyte body may be contained. One electrode of the pair of electrodes and the other electrode may be made of different materials or the same material.

(3) Second Insulating Base Part The above-mentioned "second insulating base part" is provided with a part made of insulating ceramics composed of a porous part and a non-porous part, and has an ionic conductive part (a plurality of ionic conductive parts). (Means a first ion conductive portion described later) is directly or indirectly supported through another member, and the strength of the entire element is
This is the part that guarantees it together with the insulating base. The shape and size of the second insulating base are not particularly limited, but usually,
The thickness is 0.1 mm or more (preferably 0.2 to 1.5
mm, more preferably 0.5-1.0 mm, usually 2.0
mm or less). If this thickness is less than 0.1 mm, it may be difficult to sufficiently secure the element strength. In addition, as with the first insulating base, it may be difficult to stack during manufacturing. The second insulating base may be a single layer or a multilayer.

The porous portion and the non-porous portion forming the second insulating base portion are formed of insulating ceramics capable of sufficiently exhibiting the same insulating property and heat resistance as the insulating ceramics forming the first insulating base portion. It is preferable that they are However, the insulating ceramics forming the first insulating base and the insulating ceramics forming the second insulating base may have the same composition or different compositions.

(3-1) Porous Section of Second Insulating Base Section The "porous section" is a part of the second insulating base section,
Ion conductive part (If multiple ion conductive parts are provided,
This means a portion for contacting one of a pair of electrodes constituting a first ion conductive portion described later) with the atmosphere to be measured outside the element. This porous part acts to prevent the metal composing the electrode from being poisoned by phosphorus, lead, silicon, etc., and to be measured at the time of contact with the electrode regardless of the flow velocity of the measured gas outside the element. It is possible to exert a rate-controlling effect or the like that makes the gas flow rate substantially constant. Since this porous portion can sufficiently exert these effects, it has a porosity of 5
% Or more (more preferably 20% or more, further preferably 4
It is preferably 0% or more and usually 80% or less). If the porosity is less than 5%, the responsiveness tends not to be sufficiently improved as compared with an element including a porous portion having a sufficient porosity. The porosity is the apparent volume (including the pore volume).
It is calculated from the following equation using V, mass m1 in air, and water-containing mass m2 in which water is immersed in water so that pores sufficiently contain water. {(M2-m1) / V} × 100 (%) ...

Further, in the laminated gas sensor element of the present invention, a part or the whole of the side surface of the porous portion is surrounded by the non-porous portion which constitutes the second insulating base portion. Here, "a part of the side face is surrounded" means, for example,
As shown in FIG. 1, when the porous portion 161 is formed of a polygonal plate-like body (the corners may be rounded), the side surfaces are surrounded by the non-porous portion 162 from three sides of the element. An aspect can be mentioned. In addition, as shown in FIG. 2, when a side surface is formed of a curved plate-like member having a curved shape, the side surface is formed from three sides of the element to the non-porous portion 162.
The aspect surrounded by is mentioned.

Further, as shown in FIG. 3, when the porous portion 161 is formed of a polygonal plate-like body, the side surface is surrounded by the non-porous portion 162 from two opposing directions in the element. Can be mentioned. In addition, as shown in FIG. 4, when the porous portion 161 is formed of a curved plate-like body, the side surface of the porous portion 161 is surrounded by the non-porous portion 162 from two opposing directions in the element. You can As shown in FIGS. 1 to 4, the apex (the portion where the three sides intersect) of each corner portion (the portion where the one surface and the other surface intersect) of the element is formed by the non-porous portion. It is preferable that each corner portion is also formed of a non-porous portion. This is because the tops and corners are one of the parts that are exposed to the most intense cold-hot cycle when the device is used. Since the top and the corners are formed of the non-porous portion, the thermal strength and mechanical strength of the entire element can be effectively improved.

The entire side surface of the porous portion is surrounded by the non-porous portion, for example, when the porous portion 161 is formed of a polygonal plate as shown in FIG. There may be mentioned a mode in which is surrounded by the non-porous portion 162. Further, for example, as shown in FIG. 6, when the porous portion 161 is formed of a circular plate-like body, the entire side surface is surrounded by the non-porous portion 162. Also in this case, since the corners of the element are formed by the non-porous portion as in the above case, the thermal strength and mechanical strength of the entire element can be effectively improved.

The width of the frame portion (168 or the like in FIGS. 1 to 6) surrounding a part or the whole of the side surface of the porous portion is preferably 0.2 mm or more (the width of the element is 2 to 2 mm).
At about 7 mm). When the width of the narrowest part of the frame part is less than 0.2 mm, it tends to be difficult to obtain sufficient durability against a cold cycle and impact during firing or during use. In addition, handling of the unsintered body during manufacturing may be difficult. In addition, this porous portion can be provided with a concave portion that is open on the surface that does not face the first insulating base portion (169 in FIG. 7). For the same reason, the width of the frame portion (168 in FIG. 7) forming this recess is preferably 0.2 mm or more (when the width of the element is about 2 to 7 mm).

On the other hand, in another laminated gas sensor element of the present invention, the second insulating base portion is provided with a porous portion so that air can be ventilated at least in the lateral direction, and further, the first portion of the porous portion is provided.
The non-porous portion covers at least the edge of the surface on the side not facing the insulating base. The phrase "breathable in the side surface direction" as used herein means that the porous portion is formed so as to be exposed on the side surface of the element, as shown in FIGS. However, it may be exposed only in one direction on the side surface of the element (for example, FIG. 8), may be exposed in two directions (for example, FIG. 9), or may be exposed in three directions. (For example, FIG. 10).

The one surface side of the porous portion faces the first insulating base portion, but the other surface side does not face the first insulating base portion. The edge of the porous portion on the other surface side is the “edge” of the “surface of the porous portion on the side not facing the first insulating base”. The width of this edge is not particularly limited as long as it can form a non-porous portion for pressing the porous portion toward the first insulating base portion, but is preferably 0.2 mm or more (width of element Is about 2 to 7 mm).
Furthermore, in another element of the present invention, at least this edge may be covered with a non-porous portion (see, for example, FIGS.
3)), or the entire surface of the side of the porous portion that does not face the first insulating base portion may be covered with the non-porous portion (for example, FIGS. 8 to 10).

Further, the porous portion can be provided with a concave portion which is opened on the surface not facing the first insulating base portion (169 in FIGS. 11 to 13). By providing this concave portion, the gas to be measured can be introduced not only from the side surface of the element but also from one surface side in the stacking direction of the element,
The response of the device can be improved as compared with the case where the gas to be measured is introduced from only the side surface of the device at a rate-determining rate. 11 to 13 can be exemplified as the element of such an aspect. A frame portion that forms this recess (see FIGS.
The width of 168) in No. 13 is 0.
It is preferable that the width is 2 mm or more (the width of the element is 2 to 7 m).
about m).

(4) Other parts The element of the present invention and the other element of the present invention can be provided with other parts in addition to the above-mentioned first insulating base portion, ion conductive portion and second insulating base portion. . Examples of these other parts include a heater, a cavity, an interlayer adjustment layer, and a rate-controlling introduction part. Hereinafter, these other parts will be described.

(4-1) Heater The ionic conductive portion forming the element of the present invention and the other element of the present invention can be normally activated by heating to exhibit ionic conductivity. The method for heating the ion conductive part is not particularly limited, and may be naturally heated in the environment where the element is installed (for example, heated by exhaust gas in the exhaust pipe of the internal combustion engine), or separately provided. A heater may be provided as a heating means inside. When the heater is provided, for example, it can be provided on the surface or inside of at least one of the first insulating base portion and the second insulating base portion. Further, the heater can be composed of a heating portion and a heater lead portion, the heating portion is a portion where the temperature is actually raised by the supply of electric power, and the heater lead portion is a portion which leads the electric power from the external circuit to the heating portion. is there. Although these shapes are not particularly limited, for example, the heat generating portion can be formed narrower than the heater lead portion.

(4-2) Cavity Further, the element of the present invention and another element of the present invention can have a cavity. This cavity can function as a detection chamber, a reference gas introduction chamber, or the like. The shape and size of this cavity are not particularly limited, but the height in the stacking direction is 1.0 m.
It is preferably m or less (more preferably 0.5 mm or less, further preferably 0.1 mm or less, usually 0.02 mm or more). Further, the position where the cavity is provided in the element is not particularly limited, but, for example, a first insulating base portion and an ion conductive portion (when a plurality of ion conductive portions are provided, it means a first ion conductive portion described later) It can be made to function as a reference gas introduction chamber or a detection chamber. The cavity may be closed in all directions or may be open to the outside of the device in at least one direction. Furthermore, this cavity is 1
It may be provided with only one, but may be provided with a plurality (for example, in the case of having a plurality of ion conductive parts, it may be provided so as to be sandwiched between one ion conductive part and another ion conductive part). Good).

(4-3) Interlayer adjusting layer Further, an interlayer adjusting layer for adjusting the height between layers may be provided. For example, in FIG. 19, the interlayer adjustment layer 1 is formed to match the height of the cavity 15 formed in a part between the first ion conductive portion 12 and the second ion conductive portion 13 with the height of the other portion.
52 and 154. (4-4) Rate-Controlling Introducing Section In the case where the element has a cavity as described above, a rate-controlling introducing section capable of rate-controlling and introducing the measurement gas constituting the measurement atmosphere is provided in the cavity. be able to. This rate-controlling introduction part may be formed in any manner. For example, the rate-controlling introduction porous part (1 in FIG. 17) having gas permeability enough to allow the gas to be measured to be rate-controlled and introduced.
51 and 152), or a small through-hole (15 in FIGS. 22 and 23) that allows the gas to be measured to be introduced at a rate-determining rate.
7) and the like. Examples of such a rate-controlling introduction porous portion include those having a porosity of 5 to 40% (more preferably 5 to 30%, further preferably 10 to 20%). On the other hand, examples of the through holes that are small enough to allow the gas to be measured constituting the atmosphere to be measured to be rate-controlled include a through hole having an opening area of 0.5 mm ² or less on the outer surface of the element.

[2] Correlation of Position and Size of Each Component As described above, the element of the present invention and another element of the present invention can be provided with the above-mentioned respective parts. The correlation between the position of each of these parts within the element and the size of each part will be described. The projected image of each part described below reflects the size and position of each part.
Therefore, by comparing the projected images of the respective parts, it is possible to simultaneously compare the position correlation and the size correlation of the respective parts.

(1) Correlation between Electrode and Porous Portion In the element of the present invention and the other element of the present invention, the ion conductive portion (when a plurality of ion conductive portions are provided, the above-mentioned first ion conductive portion is used) Only one of the pair of electrodes constituting (meaning) is arranged so as to come into contact with the atmosphere to be measured via the porous portion. When the element is provided with a plurality of ion conductive parts, only one of the pair of electrodes of at least one of the ion conductive parts is arranged so as to be in contact with the atmosphere to be measured through the porous part. There is. That is, it means that the projected image of the outer peripheral line of one of the pair of electrodes at least partially overlaps the projected image of the outer peripheral line of the porous portion. This overlap is 30 times the apparent area of the electrode (area that does not include the irregularities forming the porosity).
% Or more (more preferably 60% or more, further preferably the entire surface).

Other than the above-mentioned correlation between the porous portion and the electrode, the correlation of each part provided in the element of the present invention and the other element of the present invention is not particularly limited, but by making the correlation of each part more preferable, It is also possible to significantly improve the performance of the device. (2) Correlation between heat generating portion and electrode For example, in the correlation between the heat generating portion of the heater and each electrode of the ion conductive portion, it is a position where heat from the heat generating portion can be efficiently conducted to the ion conductive portion. It is preferable. That is, when the area that can actually function as a part of the ion conductive section of each of the pair of electrodes included in the ion conductive section is the actual electrode area, at least one actual electrode area of the pair of electrodes is projected. It is preferable that the projected image overlaps at least partly with the projected image of the heating portion of the heater provided in the first insulating base. Further, it is preferable that all of the projected image of the actual electrode region is included in the outline of the projected image of the heat generating portion (the heater may have a complicated shape and thus may not be included in the outer peripheral line). In particular, it is preferable that the projected images of the real electrode regions of both electrodes of the pair of electrodes are all included in the outer peripheral edge of the projected image of the heating portion.

More specifically exemplifying the above-mentioned actual electrode region, in the electrode provided in the ion conductive portion, for example, a region which is not in contact with the solid electrolyte body on one surface side is not included in the actual electrode region. Further, for example, when an element having two ion conductive parts as shown in FIG. 24 is used as an air-fuel ratio sensor element, an electrode functioning as a detection electrode among electrodes included in the ion conductive part 13 functioning as a concentration battery. In 132, the solid electrolyte body 13 is provided on one surface side.
Even if it is in contact with 1, the part where the other surface does not face the cavity (detection chamber) 15 is not included in the actual electrode area. Further, in one electrode 123 of the electrodes included in the ion conductive portion 12 that functions as an oxygen pump, a region where one surface side is in contact with the solid electrolyte body 121 and the other surface side is not facing the porous portion 161 is It is not a real electrode area.

(3) Correlation between Electrode and Solid Electrolyte Body Further, the pair of electrodes provided in the ion conductive portion may have both electrodes formed on one surface side of the solid electrolyte body, and the front and back surfaces of the solid electrolyte body may be formed. The electrodes may be formed so as to face each other. (4) Correlation Between Solid Electrolyte Body and Each Insulating Base Further, the correlation between the solid electrolyte body and the first insulating base portion or the second insulating base portion is not particularly limited, and the correlation in the longitudinal direction and the width direction of the element In the direction, the solid electrolyte body may be the same as each insulating base, or the solid electrolyte body may be smaller (usually the solid electrolyte body is not larger than these insulating bases). .

(5) Correlation Between Solid Electrolyte Body and Porous Portion The size correlation between the solid electrolyte body and the porous portion is also not particularly limited, and the solid body is solid in each of the longitudinal direction and the width direction of the device. The electrolyte body may be larger, the same or smaller than the porous part, but the solid electrolyte body may be the same size as the porous part or smaller than the porous part. Is preferred. Further, the correlation between the positions of the solid electrolyte body and the porous portion is not particularly limited, but the outer peripheral line of each part constituting the element is a part having a high probability of being a starting point of cracks or cracks compared to other parts, It is preferable that the peripheral lines of the respective parts are located so as not to contact each other. As a result, a portion which may be a starting point of a crack or a break is dispersed in the element, and the crack or the break of the element is effectively prevented. Therefore, from the size correlation and the position correlation, the projected image of the outer peripheral line of the solid electrolyte body may or may not partially overlap with the projected image of the outer peripheral line of the porous portion. It is particularly preferable to be located at.

(6) Correlation between Cavity and Porous Part Furthermore, the correlation between the cavity and the porous part in the device having the cavities exemplified in FIGS. 15, 16 and 19 described above is not particularly limited, either. The cavity in each of the longitudinal direction and the width direction of the element may be larger than the porous portion,
It may be the same or smaller. However, the cavities need not be too large, but rather tend to reduce the strength of the device, so smaller cavities are preferred. Therefore, the cavities are preferably the same or smaller in each of the longitudinal direction and the width direction of the element than the porous portion. That is, for example, a mode in which the projected image of the outer peripheral line of the cavity is positioned inside the projected image of the porous part such that the projected image of the outer peripheral line of the porous part partially overlaps or does not overlap with the projected image of the outer peripheral line of the porous part can be mentioned. Furthermore, as in the correlation between the solid electrolyte body and the porous portion, the portion that may be the starting point of cracks or cracks is dispersed in the element, so that the projected image of the outer circumference of the cavity is the porous portion. It is more preferable that it is located inside such that it does not overlap with the projected image of.

[3] Specific Structure of the Element of the Present Invention and Other Elements of the Present Invention The element of the present invention and other elements of the present invention includes each part described in the above [1], and each of these parts further includes the above [ 2]
It is arranged as described in. Although the specific configuration of such an element is not particularly limited, for example, an element including one ionic conductive portion and two ionic conductive portions as described below are provided.
Examples thereof include an element provided with one and an element provided with three ion conductive parts.

(1) Element Having One Ion Conducting Portion As illustrated in FIG. 15 (width direction sectional view) and FIG. 16 (exploded perspective view), a first insulating base portion 11 and one cavity 1
5, the first ionic conductive portion 12 and the second insulating base portion 16 are laminated in this order, and is an element having only one ionic conductive portion. This element further uses, for example, a solid electrolyte body for the first ionic conductive portion, which constitutes the first ionic conductive portion, having oxygen ionic conductivity, and causes the first ionic conductive portion to function as an oxygen concentration battery. By using the cavity as the reference gas introduction chamber, it can be used as an oxygen sensor, an air-fuel ratio sensor, or the like. The reference gas introduction chamber referred to in this element is a chamber for introducing a reference gas during measurement. As the reference gas, it is possible to use the atmosphere or various gases maintained at a constant concentration.

In such an element, for example, the first insulative base 11 has the heat generating part 114 and the heater lead part 1 between the first insulative base lower part 111 and the first insulative base upper part 112.
15 may be provided, and the heater 113 that is electrically connected to the outside from the heater extraction pad 117 via the through hole 116 may be provided. In addition, the first cavity 15 may be formed by the interlayer adjustment layer 153. Further, the first ionic conductive portion 12 is the solid electrolyte body 1 for the first ionic conductive portion.
21 and a pair of first ion conductive part electrodes 122 and 1 formed on the surface of the first ion conductive part solid electrolyte body.
23 and the interlayer adjustment layer 124.

One of the electrodes 123 for the first ion conductive portion is provided with a through hole 125 formed at an end portion of the interlayer adjusting layer 124, and the intermediate layer non-porous portion 17 is formed.
2 is connected to the electrode extraction pad 165 via a through hole 174 formed in No. 2 and a through hole 163 formed at the end of the non-porous portion 162 of the second insulating base, which will be described later, to an external circuit. Can be derived. On the other hand, the electrode 122 has a through hole 173 formed at the end of the intermediate layer non-porous portion 172 described later, and a through hole 163 formed at the end of the second insulating base non-porous portion 162 described later. It can be led to an external circuit by being connected to the electrode extraction pad 164 via.

Further, an intermediate layer having an intermediate layer porous portion 171 formed of a porous material and an intermediate layer non-porous portion 172 formed of a non-porous material can be provided. Furthermore,
Second insulating base porous portion 161 made of porous material
And a second insulating base portion having a second insulating base portion non-porous portion 162 formed of a non-porous material.
In the intermediate layer 17, the boundary 167 of the second insulating base is the first
Lead portion 12 of one of the electrodes for the ion conductive portion
It is a layer for making a structure not in direct contact with 22. The above-mentioned intermediate layer is a layer provided to prevent the electrode 122 and the boundary 167 between the porous portion 161 and the non-porous portion 162 of the second insulating base from contacting each other. It is intended to prevent thinning and disconnection.

(2) Element having two ion conductive parts As shown in FIGS. 17 (widthwise sectional view), FIG. 18 (longitudinal sectional view) and FIG. 19 (exploded perspective view), the first insulating property is obtained. Base 11, second ion conductive portion 13, one cavity 15,
This is an element including the first ion conductive portion 12 and the second insulating base portion 16 which are laminated in this order. 18 is shown in FIG.
7 is a schematic cross-sectional view taken along the line AA ′ of FIG. 7, and FIG. 17 is a schematic cross-sectional view taken along the line BB ′ of FIG. 18. This element further uses, for example, one having oxygen ion conductivity as a solid electrolyte body constituting each of the first ion conductive portion and the second ion conductive portion, and the first ion conductive portion is caused to function as an oxygen concentration battery, By making the second ion conductive portion function as an oxygen pump and using the cavity as a reference gas introduction chamber, it can be used as an air-fuel ratio sensor or the like. still,
In the detection chamber referred to as this element, oxygen contained in the atmosphere to be measured can be introduced and derived by the oxygen pumping action of the second ionic conducting part, and the concentration of oxygen in the chamber can be increased by the concentration cell action of the first ionic conducting part. It is a room where you can measure.

(3) Element Having Three Ion Conducting Parts As shown in FIGS. 20 (partially exploded perspective view) and FIG. 21 (other parts exploded perspective view), the first insulative base 11, Three
Ion conductive portion 14, second cavity 181, and third cavity 18
This is an element including three ionic conductive parts, in which each of the second ionic conductive part 13, the second ionic conductive part 13, the first cavity 15, the first ionic conductive part 12, and the second insulating base 16 is laminated in this order.
20 and 21 show one element in these two drawings, and each portion of the first cavity 15, the rate-controlling introduction portion 151 and the interlayer adjustment layer 154 shown as the bottom layer in FIG. Is arranged at the position shown by the dotted line as the virtual uppermost layer in FIG.

In this element, as the solid electrolyte body forming each of the first ionic conductive portion, the second ionic conductive portion and the third ionic conductive portion, one having oxygen ionic conductivity is used, and the first ionic conductive portion and the third ionic conductive portion are used. The 3 ionic conductive portion functions as an oxygen pump cell, the second ionic conductive portion functions as an oxygen concentration battery, the first cavity is used as a detection chamber, and the second cavity is used as a nitric oxide decomposition chamber communicating with the first cavity, By using the third cavity as a reference gas chamber, it can be used as a nitrogen oxide sensor element.

In such an element, for example, the first insulating base portion 11 is such that the heat generating portion 114 and the heater lead portion 1 are provided between the first insulating base portion lower portion 111 and the first insulating base portion upper portion 112.
It is possible to provide a heater 113 that is provided with 15, and is electrically connected to the outside by a heater lead-out line 118. Further, the third ionic conductive part 14 includes a third ionic conductive part solid electrolyte body 141, and a pair of third ionic conductive part electrodes 142 and a pair of third ionic conductive part electrodes 142 formed on the surface of the third ionic conductive part solid electrolyte layer body. 143, electrode lead-out lines 1461 and 1462 for leading out the pair of electrodes to an external circuit, an insulating layer 145 for insulating between the pair of electrodes, and the interlayer adjustment layer 1
44 may be provided.

Further, the second cavity and the third cavity can be formed by the interlayer adjusting layer 183. The second ionic conductive portion includes a second ionic conductive portion solid electrolyte body 131,
A pair of electrodes 132 and 133 for the second ion conductive portion formed on the surface of the solid electrolyte body for the second ion conductive portion;
Electrode lead lines 1361 and 1362 for leading out the pair of electrodes to an external circuit, respectively, and an interlayer adjustment layer 134 may be provided. Further, it is a path for introducing the gas to be measured from the first cavity to the second cavity, and can include first and second cavity communication passages 136 formed of a porous material.

The first cavity 15 can be formed by the interlayer adjustment layer 154. The first cavity can be provided with a rate-controlling part 151 capable of rate-controlling and introducing the gas to be measured. Further, the first ionic conductive part 12 includes a first ionic conductive part solid electrolyte body 121 and a pair of first ionic conductive part electrodes 122 and 123 formed on the surface of the first ionic conductive part solid electrolyte body 121. And electrode lead lines 1281 and 1282 for leading out the pair of electrodes to an external circuit, respectively.
And an interlayer adjustment layer 124. In addition, the intermediate layer porous portion 17 formed of a porous material
1 and an intermediate layer non-porous portion 172 formed of non-porous material
Can be provided. Further, a second insulating base portion having a second insulating base porous portion 161 made of a porous material and a second insulating base non-porous portion 162 made of a non-porous material can be provided. The intermediate layer 17 is a layer for making the boundary 167 of the second insulative base portion not in direct contact with the lead portion 1222 of one of the electrodes for the first ion conductive portion.

[4] Method for Manufacturing Element of the Present Invention and Other Elements of the Present Invention Hereinafter, a method of manufacturing the element of the present invention and another element of the present invention will be described. The method of obtaining the element of the present invention and the other element of the present invention is not particularly limited, and for example, one surface side of the unsintered first sheet that becomes the first insulating base or the unsintered second sheet that becomes the second insulating base. Can be obtained by sequentially stacking the unsintered parts (unsintered ionic conductive part, unsintered second sheet, unsintered first sheet, etc.) that become each part by sintering, and sinter the resulting unsintered element. .

Further, it can be obtained by a manufacturing method including a step of laminating into a first laminated body and a second laminated body as in the manufacturing method of the present invention. In this manufacturing method, the first sheet and the second sheet are further laminated. The non-fired portion other than the two sheets may be formed in either the first laminate or the second laminate. The manufacturing method including the step of separately laminating the first laminated body and the second laminated body, which are described below, and the step of forming the unsintered ionic conductive portion on the second laminated body side is It is suitable for manufacturing an element having two or more.

The above-mentioned "unfired first sheet" is to be fired to become the first insulating base portion, and is provided with the unfired insulating ceramic portion to be fired to become the insulating ceramic portion.
The unfired insulating ceramic portion is not particularly limited as long as it is fired and can exhibit sufficient insulating properties. The method for forming the same is not particularly limited, but for example, a ceramic raw material powder (for example, a powder composed of one or more kinds of alumina, mullite, spinel, steatite, aluminum nitride, etc., or one or more kinds thereof). Obtained by cutting the resulting green sheet into a desired size by forming a paste prepared from a powder containing as a main component), a binder, a plasticizer, etc. into a sheet by the doctor blade method, etc., and then drying it. As a raw sheet that can be
Alternatively, it can be obtained as a laminate of a plurality of these elementary sheets.

On this unsintered first sheet, an unsintered heater, which becomes a heater by sintering, can be formed on the surface or inside. The unfired heater may be a conductive layer that generates heat by being energized after firing, and its forming method is not particularly limited. For example, a raw material powder containing at least one metal of noble metal, molybdenum and rhenium, a binder, and It can be obtained by applying a paste prepared from a plasticizer or the like by a screen printing method or the like, thinly applying the paste into a desired shape on the surface of the raw sheet, and then drying. In order to obtain the first insulating base portion having the heater on the surface, it can be obtained by forming an unfired heater on the surface of a single element sheet or a multilayer element sheet in which a plurality of element sheets are laminated. .
Further, in order to obtain the first insulative base having the heater inside, a non-fired heater is formed on one surface of the raw sheet or the multi-layer raw sheet, and then another non-fired heater is covered so as to cover the non-fired heater. It can be obtained by laminating and pressing sheets or multilayer sheets and drying.

The "first laminated body" is composed of only the unsintered first sheet, or has the unsintered first sheet and other unsintered parts. The other unfired portions are the unfired second sheet that is fired to become the second insulating base and the unfired ionic conductive portion that becomes the ionic conductive portion (in an element including a plurality of ionic conductive portions as described above, It is the other part except one ion conductive part). Examples of the other unsintered portions include, for example, an unsintered interlayer adjustment layer that becomes an interlayer adjustment layer by baking, and an unsintered element that includes a plurality of ion conductive parts, the first unsintered portion is baked. Examples include a non-sintered ionic conductive part that becomes the second ionic conductive part and the third ionic conductive part.

The above "unfired second sheet" is fired to become the second insulating base portion, and is fired to become the porous portion and the non-fired porous portion to become the non-porous portion. It consists of an unfired non-porous part. These unsintered porous part and unsintered non-porous part can be formed of the same material as the unsintered insulating ceramic part constituting the unsintered first sheet. However, the unsintered porous part and the unsintered non-porous part may be made of the same material as the unsintered first sheet or different materials. The shape and size of the unfired second sheet may be different from or the same as those of the unfired first sheet.

The unsintered porous portion constituting the unsintered second sheet is not particularly limited as long as it can be sintered to exhibit sufficient air permeability, and its forming method is not particularly limited.
For example, a ceramic raw material powder (for example, a powder made of one kind or two kinds or more of alumina, mullite, spinel, steatite, aluminum nitride, etc., or having one kind or two or more kinds thereof as main components). Powder), a powder that is burnt and burnt down (for example, carbon powder, a powder composed of xanthine derivatives such as theobromine or a powder containing these as a main component), a paste prepared from a binder, a plasticizer, etc. by a doctor blade method or the like. It is possible to obtain a green sheet obtained by cutting the obtained green sheet into a desired size after being formed into a sheet shape and then drying, or as a laminate of a plurality of these green sheets.

The firing shrinkages of the unfired porous portion and the unfired non-porous portion are not particularly limited and may be the same or different, but the firing of the unfired porous portion is not limited. The shrinkage rate is smaller than the firing shrinkage rate of the non-fired non-porous portion (more preferably 0.3 to 1.5% smaller, further preferably 0.3 to 1.1% smaller, and particularly preferably 0.3. ~ 0.
7% smaller) is preferable. Since the firing shrinkage of the unfired porous portion is smaller than that of the unfired non-porous portion, the unfired non-porous portion shrinks more than the unfired porous portion during firing, and The quality part and the non-porous part are more firmly bonded, and the thermal strength and mechanical strength of the entire device obtained can be improved as compared with other cases.

The term "calcining shrinkage rate (%)" used above means that the length of a predetermined position of the unsintered body is L ₁ and the temperature is 1300 to ₁
When the length of the same position of the fired body obtained by firing at 600 ° C. is L ₂ , it means the ratio X (%) calculated from the following formula. X (%) = {(L ₁ −L ₂ ) / L ₁ )} × 100 ... The firing shrinkage rate of one of the unfired porous portions described above is higher than the firing shrinkage rate of the unfired non-porous portion. the X _3% less, the sintering shrinkage of the unsintered porous portion and _{X 1%,} a firing shrinkage of the green non-porous portion when the _{X 2%, X 3 = X} 2 -X
It means that it is ₁ .

The "unbaked ionic conductive part" includes an unbaked solid electrolyte body that is baked to form a solid electrolyte body, and a pair of unbaked electrodes that are baked to form a pair of electrodes. Of these, the unsintered solid electrolyte body is not particularly limited as long as it is calcined to exhibit ionic conductivity. The forming method is also not particularly limited, but for example, a paste prepared from a ceramic raw material powder (for example, a powder made of zirconia powder and yttria powder or a powder containing these as the main components), a binder, a plasticizer, etc. is used as a doctor blade method. After being molded by, the green sheet obtained by drying can be obtained by cutting into a predetermined size. Further, it can be obtained by molding a similar paste by a screen printing method and then drying it.

On the other hand, the unfired electrode is not particularly limited as long as it can be fired to exhibit conductivity. The forming method is not particularly limited, but for example, a paste prepared from a raw material powder containing at least one metal selected from platinum, gold, silver, palladium, iridium, ruthenium and rhodium, a binder, a plasticizer, etc. It can be obtained by applying a thin coating in a desired shape onto the surface of the unsintered solid electrolyte by a printing method or the like and then drying. Also,
The unsintered ionic conductive part can be obtained by forming this unsintered electrode on the surface of the unsintered solid electrolyte body by the above-mentioned forming method or the like.

The above "second laminate" is composed of only the unsintered second sheet and the unsintered ionic conductive part, or has the unsintered second sheet and the unsintered ionic conductive part and other unsintered parts. Is. With this other unfired part,
It is not particularly limited as long as it is an unsintered body other than the unsintered first sheet that is sintered to become the first insulating base portion. In the case of forming an unsintered element having the ionic conductive part, an unsintered ionic conductive part which is calcined to become the second ionic conductive part and the third ionic conductive part can be exemplified.

Further, when an element having a cavity to be a detection chamber, a reference gas introducing chamber, etc. is obtained, the method of forming this cavity is not particularly limited, but, for example, it is bonded to the laminated surface to be a cavity through a spacer. Thus, a cavity can be obtained after firing. Further, by filling a paste that is burned down by firing or stacking unfired sheets obtained from such a paste, it is possible to obtain a cavity after firing.

[5] Gas Sensor of the Present Invention The gas sensor of the present invention comprises the element of the present invention or another element of the present invention. The gas sensor of the present invention is not particularly limited in configuration other than these, but may be, for example, as follows. That is, the element 1 is the holder 2
11. Thermal expansion of the cushioning material 212 made of talc powder or the like and the sleeve 213 (the lead frame 25 electrically connecting the element 1 and a lead wire 26 described later is interposed between the element 1 and the sleeve 213) The structure may be fixed to jigs capable of relaxing the contraction, and further, the whole of them may be fixed to the metal shell 22. Also, the metal shell 22
Has a plurality of holes into which one side of the measured gas can be introduced,
In addition, a protector 23 is provided to cover the vicinity of the detection part of the element 1 (in FIG. 25, one end side including the heat generating part, the solid electrolyte body for the concentration battery, the solid electrolyte body for the pump cell, etc.) and protect one end side of the gas sensor 2. However, an outer cylinder 24 that protects the other end of the gas sensor 2 can be disposed on the other end of the metal shell 22. Further, from the one end side of the outer cylinder 24, water or the like is prevented from entering the separator 27 and the gas sensor 2 which are provided with through holes for branching and inserting the lead wires 26 for connecting the element 1 to an external circuit. A grommet 28 can be included.

When the exhaust gas discharged from the internal combustion engine is to be measured using the gas sensor 2 as described above,
For example, on the side surface of the metal shell 22, a mounting portion 2 having a screw shape or the like is attached.
By providing 21, the detector of the element 1 can be attached to the exhaust pipe through which the exhaust gas flows so as to project, and the detector of the element 1 can be exposed to the gas to be measured for measurement.

[0068]

The present invention will be described in more detail below with reference to FIGS. In the following, the reference numerals of each part are the same before and after firing for easy understanding. [1] Manufacturing of stacked gas sensor element (FIGS. 17 and 18)
Having a schematic cross-sectional structure shown in <1> Preparation of first laminated body (first laminated body forming step) (1) Preparation of unfired first sheet 11 Preparation of element sheets 111 and 112 Alumina powder, Butyral resin, dibutyl phthalate,
A slurry was obtained using toluene and methyl ethyl ketone. Then, this slurry was formed into two green sheets having a thickness of 0.5 mm by the doctor blade method. Next, one of the green sheets was directly used as the raw sheet 112 which is a part of the unfired first sheet. The other green sheet was provided with two through holes 116 at a predetermined position on one end side thereof to obtain a bare sheet 111.

Formation of Unfired Heater 113 A slurry was obtained using a mixed powder of platinum powder and alumina powder, butyral resin and butyl carbitol. This slurry is screen-printed on one surface of the base sheet 111 in a predetermined shape, and a non-fired heater having a narrow non-fired heat generating portion 114 which becomes the heat generating portion 114 and a wide non-fired heater lead portion 115 which becomes the heater lead portion 115. 113
Was formed.

Formation of unfired heater extraction pad 117 and connection with unfired heater 113 A slurry was obtained in the same manner as above. This slurry was screen-printed on the other surface side of the raw sheet 111 on which the non-fired heater 113 was formed so as to pass over the through hole 116 to form a non-fired heater extraction pad 117. Then, a similar slurry is applied to the through holes 116.
The unfired heater lead portion 115 is poured into the inside.
And the unfired heater extraction pad 117 were connected so as to be electrically connected after firing.

Lamination of Element Sheets 111 and 112 On one surface of the one element sheet 111 obtained up to the above where the unfired heater 113 is formed, the other element sheet 112 obtained above is attached to one surface of the second butanol. After applying a mixed liquid of butyl carbitol and butyl carbitol, they were laminated and pressure-bonded to obtain an unfired first sheet 11 having an unfired heater 113 therein.

(2) Formation of unfired second ion conductive portion (unfired concentration cell portion) 13 Unfired electrode (for second ion conductive portion reference electrode) 133
A slurry was obtained by using a mixed powder prepared by mixing platinum powder and zirconia powder, butyral resin and butyl carbitol. This slurry is screen-printed on the surface of the raw sheet 112 of the laminated body obtained in (1) above, and a wide unsintered electrode portion that becomes an electrode portion when fired and a narrow width that becomes an electrode lead portion when fired. An unfired electrode 133 having an unfired electrode lead portion was formed.

Formation of Unfired Solid Electrolyte Body (for Second Ion Conducting Part) 131 Mixed powder prepared by mixing zirconia powder and alumina powder,
A slurry was obtained using a dispersant, butyl carbitol, dibutyl phthalate and acetone. This slurry is screen-printed to a thickness of 30 μm on the unfired electrode portion formed in (2) above and dried to give the unfired solid electrolyte body 1.
I got 31.

Formation of Unbaked Interlayer Control Layer (for Second Ion Conductive Part) 134 Alumina powder, butyral resin, dibutyl phthalate,
A slurry was obtained using toluene and methyl ethyl ketone. This slurry is flush with the surface of the unsintered solid electrolyte body 131 on the unsintered electrode lead portions of the raw sheet 112 and the unsintered electrode 133, except for the unsintered solid electrolyte body 131 formed in (2) above. Screen print as
It was dried to obtain an unfired interlayer control layer 134. However, a through hole 135 for connecting the unsintered electrode lead portion of the unsintered electrode 133 to the unsintered electrode extraction pad 166 later.
Was printed so that

Unfired electrode (for second ion conductive portion) 1
Formation of 32 A slurry was obtained in the same manner as (2) above. The unsintered solid electrolyte body 131 and the unsintered interlayer control layer 134 are mixed with this slurry.
A wide unsintered electrode portion (which is formed on the surface of the unsintered solid electrolyte body 131) that is printed on the surface of the electrode, dried, and sintered to form an electrode portion, and an electrode lead portion that is sintered. The unsintered electrode 132 having a narrow unsintered electrode lead portion (this unsintered electrode lead portion was formed on the surface of the unsintered interlayer adjustment layer 134) was formed. In this way, the unsintered second ionic conductive portion 13 is laminated on the unsintered first sheet 11, and the first by the above (1) and (2).
A laminated body was obtained.

<2> Formation of Cavity (Detection Chamber) 15 and Porous Parts 151 and 152 for Introducing the Undetermined Rate Control (1) Unbaked Interlayer Control Layers (for Cavity Formation) 153 and 15
Formation of 4 A slurry was obtained in the same manner as in the above <1> (2). This slurry is screen-printed on the unfired electrode 132 and the unfired interlayer adjusting layer 134 of the first laminated body formed up to the above <1> (2) and dried to obtain the unfired interlayer adjusting layers 153 and 1.
54 was obtained. However, a through hole 155 for connecting to the unfired electrode lead portion of the unfired electrode 132 and the unfired electrode extraction pad 165 later is formed, and the unfired electrode lead portion of the unfired reference electrode 133 and the unfired electrode extraction are formed. Printing was performed so that through holes 156 for connecting to the pads 166 were formed. Further, the unbaked interlayer adjusting layer 153 and 154 is formed so that the cavity 15 is formed after baking.
It was divided into two parts, and printing was performed so that a space was formed between them.

(2) Formation of unfired rate-controlling introduction porous parts 151 and 152 Alumina powder (particle size capable of leaving voids after firing), butyral resin, dibutyl phthalate, toluene and methyl ethyl ketone to obtain a slurry. It was This slurry is screen-printed in a shape as shown in FIG. 19 on the unbaked interlayer adjusting layer 134 of the first laminate, where the unbaked interlayer adjusting layers 153 and 154 are not formed, and is not dried. Porous parts 151 and 152 for introducing rate-limiting firing were obtained. In addition, the unfired interlayer adjustment layers 153 and 154
The cavity 15 in FIG. 19 surrounded by the unfired rate-controlling introduction porous portions 151 and 152 serves as a detection chamber.

<3> Preparation of Second Laminate (1) Preparation of Unfired Second Sheet 16 Alumina powder, butyral resin, dibutyl phthalate,
A slurry for the non-porous portion was obtained using toluene and methyl ethyl ketone. This slurry was formed into a green sheet for a non-porous portion having a thickness of 500 μm by the doctor blade method. On the other hand, alumina powder, carbon powder, butyral resin, dibutyl phthalate, toluene and methyl ethyl ketone were used to obtain a slurry for a porous portion. This slurry was formed into a green sheet for a porous portion having a thickness of 500 μm by the doctor blade method. A sheet having an unsintered porous part 161 serving as the porous part 161 is formed from one of these two types of green sheets on one end side of the unsintered non-porous part 162 serving as the non-porous part as shown in FIG. did. Next, three holes to be the through holes 153 were provided to obtain the unfired second sheet 16.

(2) Formation of Unfired Intermediate Layer 17 Two kinds of slurries for a porous portion and a non-porous portion similar to the above <3> (1) were obtained. Of these, the slurry for the porous portion is used as the unfired second sheet 1 obtained in the above <3> (1).
6 was screen-printed so as to cover the unsintered porous part 161 provided in No. 6, and dried to form the unsintered intermediate layer porous part 171 to be the porous part 171 of the intermediate layer 17. Next, the slurry for the non-porous portion is screen-printed on the surface of the unfired second sheet 16 on which the unfired intermediate layer porous portion 171 is not formed, and dried to form the non-porous portion of the intermediate layer 17. The non-fired intermediate layer non-porous portion 172 to be the portion 172 was formed. However, a through hole 175 for connecting the unfired electrode 133 and the unfired electrode extraction pad 166 later is formed, and the unfired electrode 132 and the unfired first electrode 12 are formed.
3 and the unfired electrode lead-out pad 165 are formed with through holes 174, and the unfired electrode 122 is formed.
Printing was performed so as to form a through hole 173 for connecting the unfired electrode extraction pad 164. The intermediate layer 17 composed of the unsintered intermediate layer 17 has the electrode 122.
And the porous portion 161 and the non-porous portion 1 of the second insulating base
It is a layer provided to prevent the boundary 167 from coming into contact with 62, and prevents the electrode from being thinned or broken.

(3) Formation of unfired first ionic conductive portion (unfired pump cell) 12 Formation of unfired electrode 122 A slurry was obtained in the same manner as in the above <1> (2). This slurry is screen-printed on the surface of the unfired intermediate layer 17 obtained above, and a wide unfired electrode portion is fired to form an electrode portion, and a narrow unfired electrode lead is fired to form an electrode lead portion. An unfired electrode 122 having a portion was formed.

Formation of Unfired Solid Electrolyte Body (for First Ion Conductive Part) 121 A slurry was obtained in the same manner as in the above <1> (2). This slurry was screen-printed to a thickness of 30 μm on the green electrode portion of the green electrode 122 obtained above and dried to obtain a green solid electrolyte body 121.

Formation of Unfired Interlayer Control Layer 124 A slurry was obtained in the same manner as in the above <1> (2). Except for the unsintered solid electrolyte body 121 obtained above, this slurry is placed on the unsintered electrode lead portions of the unsintered intermediate layer 17 and the unsintered electrode 122 so that the height of the surface of the unsintered solid electrolyte body 121 is matched. Was screen-printed and dried to obtain an unfired interlayer control layer 124. However, a through hole 126 for connecting the unfired electrode 133 and the unfired electrode extraction pad 166 later is formed, and the unfired electrode 132 and the unfired electrode 123 (not formed at this time) and the unfired electrode extraction are formed. Through hole 12 for connecting to the pad 165
Printing was carried out so that 5 was formed.

Formation of Unfired Electrode 123 A slurry was obtained in the same manner as in the above <1> (2). The slurry is printed on the surfaces of the unsintered solid electrolyte body 121 and the unsintered interlayer control layer 124, dried, and then sintered to form a wide unsintered electrode portion (the unsintered electrode portion is an unsintered solid electrolyte layer). (Formed on the surface of the body 121) and a thin unfired electrode lead portion (which is formed on the surface of the unfired interlayer adjustment layer 124) that is fired to form an electrode lead portion. The electrode 123 was formed. In this way, the second laminated body was obtained by the above (1) to (3).

<4> Joining of First Laminated Body and Second Laminated Body This surface of the first laminated body in which the cavity 15 and the unfired rate-controlling introduction porous portions 151 and 152 are formed on one surface side, After applying the mixed solution of the second butanol and butyl carbitol to the surface of the two-layered body on which the unfired electrode 132 is formed,
The unfired element 1 was obtained by bonding and pressure bonding. <5> Degreasing and firing The unfired element 1 obtained up to the above <4> was subjected to a degreasing treatment in an air atmosphere. Then, the laminated gas sensor element 1 was obtained by firing at 1300 to 1600 ° C. in the air atmosphere.

<6> Manufacture of Gas Sensor A gas sensor 2 shown in FIG. 25 was manufactured using the element 1 obtained up to the above <5>. In this gas sensor 2,
The element 1 includes a ceramic holder 211, a talc powder 212 and a ceramic sleeve 21 which are housed in a metal shell 22.
3 (the lead frame 25 is provided between the sensor element 1 and the ceramic sleeve 213, and the upper end of the sensor element 1 is located in the ceramic sleeve 213). A metallic protector 23 having a double structure having a plurality of holes covering the lower portion of the sensor element 1 is attached to the lower portion of the metallic shell 22, and an outer cylinder 213 is attached to the upper portion of the metallic shell 22. There is. Further, a ceramic separator 27 and a grommet 28 provided with through holes for branching and inserting lead wires 26 for connecting the sensor element 1 to an external circuit are provided on the upper portion of the outer cylinder 24.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of a laminated gas sensor element of the present invention including an example of a second insulating base.

FIG. 2 is a schematic perspective view of a laminated gas sensor element of the present invention including a second insulating base portion of another example.

FIG. 3 is a schematic perspective view of a laminated gas sensor element of the present invention including a second insulating base portion of yet another example.

FIG. 4 is a schematic perspective view of a laminated gas sensor element of the present invention including a second insulating base portion of yet another example.

FIG. 5 is a schematic perspective view of a laminated gas sensor element of the present invention including a second insulating base portion of yet another example.

FIG. 6 is a schematic perspective view of a laminated gas sensor element of the present invention including a second insulating base portion of yet another example.

FIG. 7 is a schematic perspective view of a laminated gas sensor element of the present invention including a second insulating base portion of yet another example.

FIG. 8 is a schematic perspective view of a laminated gas sensor element of the present invention including a second insulating base portion of yet another example.

FIG. 9 is a schematic perspective view of a laminated gas sensor element of the present invention including a second insulating base portion of yet another example.

FIG. 10 is a schematic perspective view of a laminated gas sensor element of the present invention including a second insulating base portion of yet another example.

FIG. 11 is a schematic perspective view of a laminated gas sensor element of the present invention including a second insulating base portion of yet another example.

FIG. 12 is a schematic perspective view of a laminated gas sensor element of the present invention including a second insulating base portion of yet another example.

FIG. 13 is a schematic perspective view of a laminated gas sensor element of the present invention including a second insulating base portion of yet another example.

FIG. 14 is a schematic cross-sectional view in the width direction showing an example of the laminated gas sensor element of the present invention.

FIG. 15 is a schematic cross-sectional view in the width direction showing another example of the laminated gas sensor element of the present invention.

16 is a schematic exploded perspective view of the laminated gas sensor element of the present invention shown in FIG.

FIG. 17 is a schematic cross-sectional view in the width direction showing still another example of the laminated gas sensor element of the present invention.

18 is a schematic cross-sectional view in the longitudinal direction of the laminated gas sensor element of the present invention shown in FIG.

FIG. 19 is a schematic exploded perspective view of the laminated gas sensor element of the present invention shown in FIGS. 17 and 18.

FIG. 20 is a schematic exploded perspective view showing a part of another example of the laminated gas sensor element of the present invention.

FIG. 21 is a schematic exploded perspective view showing another portion of another example of the laminated gas sensor element of the present invention.

FIG. 22 is a schematic cross-sectional view in the width direction showing still another example of the laminated gas sensor element of the present invention.

FIG. 23 is a schematic cross-sectional view in the width direction showing still another example of the laminated gas sensor element of the present invention.

FIG. 24 is a schematic cross-sectional view in the width direction showing still another example of the laminated gas sensor element of the present invention, for explaining the actual electrode region of the present invention.

FIG. 25 is a schematic cross-sectional view of an example of the gas sensor of the present invention.

FIG. 26 is a schematic perspective view showing an example of a conventional laminated gas sensor element.

FIG. 27 is a schematic perspective view showing another example of the conventional laminated gas sensor element.

[Explanation of symbols]

1; laminated gas sensor element, 11; first insulating base, 1
11; lower part of first insulating base (elementary sheet), 112; first
Insulating base upper part (elementary sheet), 113; heater, 11
4; Heat generating part, 115; Heater lead part, 117; Heater extraction pad, 118; Heater extraction line, 12; Ion conductive part (first ion conductive part), 121; Solid electrolyte body (first
(For ion conductive part), 122, 123; electrodes (first pump electrode and second pump electrode), 1221; electrode part, 122
2; electrode lead portion, 124; interlayer adjustment layer (for first ion conductive portion), 1271, 1272; insulating layer, 1281, 1
282; electrode lead wire (for first ion conductive portion), 13; ion conductive portion (second ion conductive portion), 131; solid electrolyte body (for second ion conductive portion), 132; electrode (detection electrode), 133 Electrode (reference electrode), 134; Interlayer control layer (for second ion conductive portion), 136; First and second inner chamber communication paths, 1371, 1372; Insulating layer, 1381, 138
2; electrode lead wire (for second ion conductive portion), 14; ion conductive portion (third ion conductive portion), 141; solid electrolyte body (for third ion conductive portion), 142; electrode (detection electrode),
143; electrode (reference electrode), 144; interlayer adjustment layer (third
(For ion conductive part), 145; insulating layer, 1461, 146
2; electrode lead wire (for third ionic conductive portion), 15; cavity (first cavity), 151, 152; rate-introducing porous portion, 1
53, 154; interlayer adjusting layer (for forming first cavity), 15
7: through-hole, 16; second insulating base portion, 161; porous portion, 162; non-porous portion, 164, 165, 166; electrode extraction pad, 167; boundary between porous portion and non-porous portion, 168; Frame part, 169; Recessed part, 17; Intermediate layer, 17
1; Intermediate layer porous part, 172; Intermediate layer non-porous part, 18
1; cavity (second cavity), 182; cavity (third cavity), 1
83; Interlayer control layer (for forming second and third cavities), 2; Gas sensor, 211; Holder, 212; Buffer material, 213; Sleeve, 22; Metal shell, 221; Mounting part, 23; Protector, 24; Outer cylinder , 25; lead frame, 26; lead wire, 27; separator, 28; grommet.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masamichi Hiraiwa             14-18 Takatsuji-cho, Mizuho-ku, Nagoya-shi Japan special             Within Toyo Co., Ltd.

Claims (9)

[Claims] 1. A first insulating base portion, an ion conductive portion having a solid electrolyte body and a pair of electrodes formed on the surface of the solid electrolyte body, and a second insulating base portion facing the first insulating base portion. And 2 are laminated in this order, the second insulating base portion is provided with a porous portion that can ventilate at least in the front-back direction, and a part of the side surface of the porous portion or the entire side surface is a non-porous portion. A laminated gas sensor element, which is surrounded and arranged such that only one of the pair of electrodes is in contact with the atmosphere to be measured through the porous portion. 2. The side surface of the porous portion is entirely surrounded by the non-porous portion, and the width of a frame portion surrounding the side surface of the porous portion is 0.2 mm or more. The laminated gas sensor element according to claim 1. 3. A concave portion is provided on a side of the second insulating base portion that does not face the first insulating base portion, and is ventilated through the concave portion and the porous portion in a front-back direction of the second insulating base portion. 1. The laminated gas sensor element according to 1. 4. A first insulating base portion, an ion conductive portion having a solid electrolyte body and a pair of electrodes formed on the surface of the solid electrolyte body, and a second insulating base portion facing the first insulating base portion. Are laminated in this order, and the second insulating base portion is provided with a porous portion so that air can be ventilated at least in the lateral direction, and the side of the porous portion that does not face the first insulating base portion is further provided. A non-porous portion that covers at least an edge of the surface of the electrode, and only one of the pair of electrodes is arranged so as to come into contact with the atmosphere to be measured through the porous portion. And a laminated gas sensor element. 5. The laminated gas sensor element according to claim 1, wherein the porous portion has a porosity of 5 to 80%. 6. A cavity serving as a reference gas introduction chamber or a detection chamber is provided between the first insulating base portion and the ion conductive portion, and the second insulation of the cavity is provided in the width direction of the laminated sensor element. The projected image of the outer peripheral line on the side opposite to the base portion overlaps with the projected image of the outer peripheral line of the porous portion or is located inside the projected image of the outer peripheral line of the porous portion. The laminated gas sensor element according to any one of 1. 7. A cavity provided with another ion conductive portion between the first insulating base portion and the ion conductive portion, and serving as a detection chamber between the ion conductive portion and the other ion conductive portion. In the width direction of the laminated sensor element, the projected image of the outer peripheral line of the cavity on the side facing the second insulating base portion overlaps with the projected image of the outer peripheral line of the porous portion, or The laminated gas sensor element according to any one of claims 1 to 5, which is located inside a projected image of an outer peripheral line of the quality portion. 8. The method for manufacturing a laminated gas sensor element according to claim 1, wherein the first laminated body includes an unsintered first sheet that serves as the first insulating base. And a second laminate including the unsintered second sheet that serves as the second insulating base and the unsintered ionic conductive portion that serves as the ionic conductive portion. The 2 sheet includes an unsintered non-porous portion that is calcined to become the non-porous portion and an unsintered porous portion that is calcined to become the porous portion. A method for manufacturing a laminated gas sensor element, wherein the firing shrinkage is equal to or greater than the firing shrinkage of the unfired porous portion. 9. A gas sensor comprising the laminated gas sensor element according to any one of claims 1 to 7.