JPH09105734A - Ion electrode and its manufacture - Google Patents
Ion electrode and its manufactureInfo
- Publication number
- JPH09105734A JPH09105734A JP7291848A JP29184895A JPH09105734A JP H09105734 A JPH09105734 A JP H09105734A JP 7291848 A JP7291848 A JP 7291848A JP 29184895 A JP29184895 A JP 29184895A JP H09105734 A JPH09105734 A JP H09105734A
- Authority
- JP
- Japan
- Prior art keywords
- ion
- sensitive member
- electrode
- sealing material
- support
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Measuring Oxygen Concentration In Cells (AREA)
Abstract
Description
【0001】[0001]
【発明の属する技術分野】本発明は、化学工業、食品工
業、医療、環境計測等において、溶液中に存在する特定
のイオンの濃度を測定するために用いられるイオン電極
であって、特に内部液を必要としない全固体型のイオン
電極及びその製造方法に関する。TECHNICAL FIELD The present invention relates to an ion electrode used for measuring the concentration of a specific ion existing in a solution in the chemical industry, food industry, medical care, environmental measurement, etc. TECHNICAL FIELD The present invention relates to an all-solid-state type ion electrode that does not need to be manufactured and a manufacturing method thereof.
【0002】[0002]
【従来の技術】溶液中の特定のイオン濃度を測定する手
法として、イオン選択性電極(以下、イオン電極とい
う)を用いるイオン電極法が知られている。ここで、イ
オン電極とは、溶液中の陰イオンまたは陽イオンの活量
(熱力学的補正濃度)に応じて発生する電位差を検出す
るための電極をいい、通常、特定のイオン種に選択的に
感応するイオン感応部材(イオン感応体)を備えてい
る。2. Description of the Related Art As a method of measuring a specific ion concentration in a solution, an ion electrode method using an ion selective electrode (hereinafter referred to as an ion electrode) is known. Here, the ion electrode means an electrode for detecting a potential difference generated according to the activity (thermodynamically corrected concentration) of anion or cation in a solution, and is usually selective for a specific ion species. It is equipped with an ion sensitive member (ion sensitive body) that is sensitive to.
【0003】上記イオン電極の感応部材には、従来より
ガラス膜または有機膜が用いられているが、このような
イオン電極は感応部材自体が非常に薄い膜状であるた
め、機械的強度や耐久性、化学的安定性等に乏しいとい
う問題がある。また、上記のイオン電極には電解質を含
む内部標準液を使用するタイプのものが主であり小型化
に適さず、多量の被測定液を必要とすると共に、メンテ
ナンスに手間がかかるという問題もある。Conventionally, a glass film or an organic film has been used as a sensitive member of the ion electrode. However, since the sensitive member itself of such an ion electrode is a very thin film, mechanical strength and durability are improved. There is a problem that it is poor in sex and chemical stability. In addition, the above-mentioned ion electrode is mainly of a type that uses an internal standard solution containing an electrolyte, is not suitable for downsizing, requires a large amount of solution to be measured, and has a problem that maintenance is troublesome. .
【0004】これに対して、イオン感応部材に無機塩や
固体電解質などからなる固体膜を用いて強度や耐久性、
化学的安定性の改善を図ったイオン電極が提案されてい
る。このようなイオン電極は、上記固体膜自体の耐水性
が必ずしも十分なものではないため、固体膜に直接リー
ド線を付けて電位を取り出す方法、またはイオンブリッ
ジとも呼ばれる固体状または半固体状の導電性ブリッジ
材を介してリード線を付けて電位を取り出す方法等によ
って、内部標準液を必要としない、いわゆる全固体型電
極として構成されている。On the other hand, a solid film made of an inorganic salt or a solid electrolyte is used for the ion sensitive member to improve strength and durability,
Ion electrodes have been proposed that have improved chemical stability. In such an ion electrode, since the water resistance of the solid film itself is not always sufficient, a method of directly attaching a lead wire to the solid film to take out an electric potential, or a solid or semi-solid conductive also called an ion bridge A so-called all-solid-state electrode that does not require an internal standard solution is formed by a method in which a lead wire is attached via a flexible bridge material to take out an electric potential.
【0005】[0005]
【発明が解決しようとする課題】このような全固体型の
イオン電極では、使用時に支持体内側に被測定液が浸入
してリード線と接触し電気的導通(短絡)を生じると、
本来の目的たるイオン濃度に応じて発生すべき電位に大
きな影響を及ぼし正確な測定ができなくなるため、イオ
ン感応部材と支持体との間(空隙)は液密的に封止し、
被測定液の浸入を防ぐ必要がある。その対策として、イ
オン感応部材と支持体とを固着して電極を作製する際
に、樹脂系の接着剤等がシール材として用いられる。In such an all-solid-state ion electrode, when the liquid to be measured enters the inside of the support during use and comes into contact with the lead wire, causing electrical conduction (short circuit),
Since the potential that should be generated according to the originally intended ion concentration is greatly affected and accurate measurement cannot be performed, the space (void) between the ion sensitive member and the support is liquid-tightly sealed,
It is necessary to prevent the measured liquid from entering. As a countermeasure, a resin adhesive or the like is used as a sealing material when the electrode is manufactured by fixing the ion sensitive member and the support.
【0006】しかし、このようなイオン電極において
は、その検出電位について電極間の個体間のばらつきが
大きい上、その応答時間についても長くかかるものがあ
り、電極個々に検量線の作成や使用条件等の調整を必要
とするため、手間がかかるという問題があった。本発明
はこのような欠点を解消するためになされたものであ
り、その目的とするところは、応答時間が短く、再現性
に優れ、個体間のばらつきの小さい全固体型のイオン電
極を提供することにある。However, in such an ion electrode, there is a large variation in the detection potential among the electrodes and a long response time in some cases. However, there is a problem in that it takes time and effort because it requires adjustment. The present invention has been made to solve such drawbacks, and an object thereof is to provide an all-solid-state ion electrode having a short response time, excellent reproducibility, and small variation among individuals. Especially.
【0007】[0007]
【課題を解決するための手段】本発明は、イオン感応部
材と支持体とを固着するシール材が検出電圧に影響を及
ぼしている点に着目してなされたものであり、本発明の
請求項1に係るイオン電極は、固体電解質からなるイオ
ン感応部材と、該イオン感応部材上に配置された内部電
極と、前記イオン感応部材の検知面と前記内部電極とを
仕切るべくシール材で固着されてなる支持体とを備え、
前記イオン感応部材と支持体との固着面間隔が内部電極
側が次第に大きくなるように設けられていることを特徴
とする。このとき、前記イオン感応部材または支持体の
少なくとも一方に、面取り、丸みまたはテーパーが設け
られ、前記イオン感応部材と支持体との固着面のなす角
度が10〜80度(更には20〜60度)であることが
望ましい。また、前記固体電解質がイオン伝導性セラミ
ックスからなることが望ましい。The present invention has been made by paying attention to the fact that the sealing material for fixing the ion sensitive member and the support has an influence on the detection voltage. The ion electrode according to No. 1 has an ion sensitive member made of a solid electrolyte, an internal electrode arranged on the ion sensitive member, and a sealing material fixed to separate the detection surface of the ion sensitive member from the internal electrode. And a support that becomes
It is characterized in that a fixing surface interval between the ion sensitive member and the support is provided such that the inner electrode side is gradually increased. At this time, at least one of the ion-sensitive member and the support is provided with chamfering, rounding or taper, and the angle formed by the fixing surface between the ion-sensitive member and the support is 10 to 80 degrees (further 20 to 60 degrees). ) Is desirable. Further, it is desirable that the solid electrolyte is made of ion conductive ceramics.
【0008】また、本発明の請求項6に係るイオン電極
の製造方法は、固体電解質からなるイオン感応部材と、
該イオン感応部材上に配置された内部電極と、前記イオ
ン感応部材の検知面と前記内部電極とを仕切るべく固着
されてなる支持体とを備えたイオン電極の製造方法にお
いて、前記イオン感応部材と支持体とをその固着面間隔
が内部電極側が次第に大きくなるように配置し、液状ま
たはペースト状のシール材を注入した後、これを硬化さ
せてイオン感応部材と支持体とを固着する工程を有する
ことを特徴とする。このとき、前記シール材として、そ
の25℃における粘度が10〜700Pa・sであるこ
とが望ましく、更に望ましい範囲は50〜500Pa・
sである。A method for manufacturing an ion electrode according to a sixth aspect of the present invention is an ion sensitive member comprising a solid electrolyte,
A method for producing an ion electrode, comprising: an internal electrode disposed on the ion-sensitive member; and a support body fixed to separate the detection surface of the ion-sensitive member and the internal electrode, wherein the ion-sensitive member comprises: There is a step of arranging the supporting body so that the fixing surface distance becomes gradually larger on the internal electrode side, injecting a liquid or paste-like sealing material, and then curing the sealing material to fix the ion-sensitive member and the supporting body. It is characterized by At this time, the viscosity of the sealing material at 25 ° C. is preferably 10 to 700 Pa · s, more preferably 50 to 500 Pa · s.
s.
【0009】[0009]
【発明の実施の形態】本発明のイオン電極は、上述した
ように、固体電解質からなるイオン感応部材と支持体と
の固着部に予め面取り、丸みまたはテーパーを公知の加
工法等で形成しておき、イオン感応部材と支持体との固
着面間隔が内部電極側が次第に大きくなるように配置
し、固着部に楔型の空間を設けてシール材の滞留部を形
成した上で両者をシール材で固着してなるものである。BEST MODE FOR CARRYING OUT THE INVENTION As described above, in the ion electrode of the present invention, chamfering, roundness or taper is formed in advance at a fixed portion between an ion sensitive member made of a solid electrolyte and a support by a known processing method or the like. Then, the fixed surface distance between the ion sensitive member and the support is arranged so that the internal electrode side becomes gradually larger, and a wedge-shaped space is provided in the fixed part to form a retention part of the sealing material, and then both are sealed by the sealing material. It is fixed.
【0010】上記固体電解質としては、イオン伝導性を
有する固体材料であって、たとえば、ナシコンセラミッ
クス(Na1+XZr2SiXP3-XO12,0≦x≦3)、ベ
ータ・アルミナセラミックス(M2O・nAl2O3,5
≦n≦11,Mはアルカリ金属)、フッ化ランタン(L
aF3)、ハロゲン化銀、硫化銀、硫化銅、硫化カドミ
ウム等を用いることができる。イオンの伝導種は前記固
体電解質の材料によってほぼ決まるものであるが、ナト
リウムの他に、カリウム、リチウム等のアルカリ族のイ
オン、水素イオン、酸素イオン、フッ素イオン、炭酸イ
オンなどが挙げられる。The above-mentioned solid electrolyte is a solid material having ion conductivity, for example, Nasicon ceramics (Na 1 + X Zr 2 Si X P 3-X O 12 , 0 ≦ x ≦ 3), beta. Alumina ceramics (M 2 O ・ nAl 2 O 3 , 5
≤n≤11, M is an alkali metal, lanthanum fluoride (L
aF 3 ), silver halide, silver sulfide, copper sulfide, cadmium sulfide and the like can be used. The conductive species of the ions are substantially determined by the material of the solid electrolyte, and examples thereof include alkaline ions such as potassium and lithium, hydrogen ions, oxygen ions, fluorine ions, carbonate ions and the like in addition to sodium.
【0011】上記固体電解質のうち、ナシコン、β−ア
ルミナ等のイオン伝導性セラミックスは本発明のイオン
感応部材として特に好ましいものである。これらの材料
を用いる場合は緻密な焼結体であることが望ましく、そ
の製造は、イオン感応部材の形状や大きさに応じて公知
の成形法(たとえば、金型プレス成形法、スリップキャ
スト成形法等)及び焼成法を適宜用いることができる。
セラミックス焼結体は機械的強度が高く、機械加工性に
も優れるため、焼結後に角部に面取り加工や丸み加工を
施したり、テーパー形状に研削加工を施すことも容易で
あるが、焼結前の成形体の段階で上記の加工を施した後
に焼結させることも可能である。Of the above solid electrolytes, ion conductive ceramics such as NASICON and β-alumina are particularly preferable as the ion sensitive member of the present invention. When these materials are used, it is desirable that the material be a dense sintered body, and the production thereof is performed according to the shape and size of the ion-sensitive member by a known molding method (for example, die press molding method, slip cast molding method). Etc.) and the firing method can be appropriately used.
Since the ceramics sintered body has high mechanical strength and excellent machinability, it is easy to chamfer or round the corners or grind the tapered shape after sintering. It is also possible to sinter after performing the above-mentioned processing in the stage of the former molded body.
【0012】上記支持体としては、ガラス、セラミック
ス焼結体、アクリル樹脂、ABS樹脂等の材質のものを
用いることができるが、電気絶縁性に優れ、加工性、取
り扱い性等を備えるものであれば特に限定されず、これ
らをイオン電極の使用形態に応じた各種形状、たとえば
円筒状、板状等に加工して用いることができる。The support may be made of a material such as glass, a ceramics sintered body, an acrylic resin, an ABS resin, etc., provided that it has excellent electric insulation, workability and handleability. There is no particular limitation, and these can be used after being processed into various shapes depending on the usage of the ion electrode, such as a cylindrical shape and a plate shape.
【0013】本発明のイオン電極では、イオン感応部材
と支持体との固着面間隔が内部電極側が次第に大きくな
るように設けられている。それには、前記イオン感応部
材または支持体の少なくとも一方の側の角部に面取り若
しくは丸みを設けるか、またはこれらの固着部分をテー
パー形状とすることで達成され、この部分にシール材の
滞留部が構成される。このとき、前記イオン感応部材と
支持体との固着面のなす角度が80度より大きいと、シ
ール材が滞留部に留まらずに内部電極側へ滲み出して接
触してしまうおそれがあるので好ましくない。より好ま
しくは60度以下である。一方、イオン感応部材と支持
体との固着面のなす角度が10度より小さいと、十分な
滞留部が確保できない上に毛細管力により固着面の端部
からシール材が滲み出すおそれがあり、また、シール材
を滞留部に注入する際の作業性も劣るため好ましくな
い。より好ましくは20度以上であり、最も好ましいの
は30〜45度である。In the ion electrode of the present invention, the fixed surface distance between the ion sensitive member and the support is provided so that the internal electrode side gradually becomes larger. This can be achieved by chamfering or rounding the corners on at least one side of the ion-sensitive member or the support, or by tapering these fixed parts, and the retention part of the sealing material is provided in this part. Composed. At this time, if the angle formed by the fixing surface between the ion-sensitive member and the support is larger than 80 degrees, the sealing material may not stay in the staying portion but may exude to the internal electrode side and come into contact therewith, which is not preferable. . More preferably, it is 60 degrees or less. On the other hand, if the angle formed by the fixing surface between the ion-sensitive member and the support is less than 10 degrees, a sufficient retention portion cannot be secured, and the sealing material may exude from the end of the fixing surface due to capillary force. However, the workability when injecting the sealing material into the retention portion is also inferior, which is not preferable. It is more preferably 20 degrees or more, and most preferably 30 to 45 degrees.
【0014】前記内部電極としては、リード線(銅線)
を用いてこれを直接イオン感応部材に取り付けて構成し
てもよいが、イオンブリッジとも呼ばれる固体状または
半固体状の導電性ブリッジ材を介してイオン感応部材に
つけると安定した電位が取り出せるため、好ましい。前
記導電性ブリッジ材としては、導電性と接着性とを兼ね
備えるものが望ましい。たとえば、好ましい例として、
カーボン粒子をフェノール樹脂と混合してなる熱硬化性
のカーボンペーストをイオン感応部材に塗布し、リード
線の芯線端部を埋入または接触させた状態で加熱してペ
ーストを接着硬化させるとよい。また、このカーボンペ
ーストにさらに、塩化ナトリウム、塩化銀等の塩類を加
えたものを導電性ブリッジ材として用いることにより応
答性の向上や電位の安定化を図ることもできる。As the internal electrodes, lead wires (copper wires) are used.
It may be configured by directly attaching it to the ion sensitive member using, but because a stable potential can be taken out when it is attached to the ion sensitive member via a solid or semi-solid conductive bridge material also called an ion bridge, preferable. The conductive bridge material preferably has both conductivity and adhesiveness. For example, as a preferred example,
It is preferable that a thermosetting carbon paste prepared by mixing carbon particles with a phenol resin is applied to the ion-sensitive member, and the paste is adhesively cured by heating while the end of the core wire of the lead wire is embedded or in contact. Further, by using the carbon paste to which salts such as sodium chloride and silver chloride are added as a conductive bridge material, it is possible to improve the response and stabilize the potential.
【0015】前記シール材としては、接着性、絶縁性及
び耐水性に優れたものであって、イオン感応部材と支持
体あるいはリード線と支持体とによく濡れ、密着して液
密性を維持できるものが望ましく、例えば、エポキシ樹
脂系、シリコーン樹脂系、ポリウレタン樹脂系、アクリ
ル樹脂系、フェノール樹脂系等の接着剤が挙げられる。
特に好ましいのはエポキシ樹脂系接着剤である。また、
その粘性が低すぎると、シール材が滞留部に留まらずに
内部電極を構成する導電性ブリッジ材やリード線芯線と
接触してしまう恐れがあるので、25℃における粘度と
して10Pa・s以上、より好ましくは50Pa・s以
上のものを用いる方がよい。一方、粘性が高すぎると、
固着部に均一にシール材が浸透せず、液密的かつ十分な
強度の固着ができないため、700Pa・s以下、より
好ましくは500Pa・s以下のものを用いる方がよ
い。なお、上記シール材はその粘度を適当な溶剤を用い
て調製して用いることもできる。The sealing material has excellent adhesiveness, insulation and water resistance, and is well wetted and adhered to the ion sensitive member and the support or the lead wire and the support to maintain liquid tightness. What is possible is desirable, and examples thereof include epoxy resin-based, silicone resin-based, polyurethane resin-based, acrylic resin-based, and phenol resin-based adhesives.
Epoxy resin adhesives are particularly preferable. Also,
If the viscosity is too low, the sealing material may come into contact with the conductive bridge material and the lead core wire that form the internal electrodes without staying in the retention area. Therefore, the viscosity at 25 ° C. is 10 Pa · s or more, It is preferable to use 50 Pa · s or more. On the other hand, if the viscosity is too high,
Since the sealing material does not uniformly penetrate into the fixed portion and liquid-tightness and sufficient strength cannot be fixed, it is preferable to use 700 Pa · s or less, more preferably 500 Pa · s or less. The sealing material can be used by adjusting its viscosity using an appropriate solvent.
【0016】[0016]
【作用】本発明のイオン電極では、イオン感応部材と支
持体との固着部となるべき部分を面取り、丸み、テーパ
ー等の形状としておくことにより、両者を固着させるべ
く組み合わせたときにその固着面間隔が内部電極側に向
かって次第に大きくなるように構成されたシール材の滞
留部が形成される。上記の面取り、テーパー等の加工
は、これらと同様に滞留部を形成可能な溝加工や段付き
加工、ネジ加工等といった複雑且つ煩雑な加工に比べて
比較的単純である点で有利でもある。そして、イオン電
極を組み立てる際に、イオン感応部材と支持体との固着
面に液状若しくはペースト状のシール材を注入すると、
過剰のシール材が固着面から滲み出したり押し出される
が、上記滞留部のところで過剰のシール材が凹状のメニ
スカスを形成して留められる。In the ion electrode of the present invention, the portion to be the fixing portion between the ion sensitive member and the support is chamfered, rounded, tapered or the like so that the fixing surface when the both are fixed to each other is fixed. A stagnation portion of the sealing material is formed so that the gap gradually increases toward the internal electrodes. The above-described chamfering, tapering, and the like are also advantageous in that they are relatively simple as compared with complicated and complicated processing such as groove processing, step processing, and screw processing capable of forming a retaining portion like these. Then, when assembling the ion electrode, if a liquid or paste sealing material is injected into the fixing surface between the ion sensitive member and the support,
The excess sealing material exudes or is extruded from the fixed surface, but the excess sealing material forms a concave meniscus and is retained at the retaining portion.
【0017】その結果、シール材が内部電極を構成する
導電性ブリッジ材やリード線の部分にまで達してこれら
と接触することが防止され、ノイズの発生等を抑えて測
定精度が維持される。また、シール材の使用量が電極個
々に異なっていても、シール材が介在する固着面積が滞
留部で隔されることによりほぼ一定に保たれるため、シ
ール材とイオン感応部材との接触面積の差による検出電
位のばらつきが低減される。As a result, the sealing material is prevented from reaching the conductive bridge material and the lead wire forming the internal electrode and coming into contact therewith, and the generation of noise is suppressed and the measurement accuracy is maintained. Further, even if the amount of the sealing material used varies from electrode to electrode, the fixed area where the sealing material intervenes is kept almost constant by being separated by the retention area, so the contact area between the sealing material and the ion sensitive member is large. The variation of the detected potential due to the difference of is reduced.
【0018】[0018]
【実施例】以下、本発明の実施例を図面に基づいて説明
する。 〔実施例1〕実施例1に係る本発明のイオン電極の断面
図を図1に示す。イオン電極1は、支持体2、イオン感
応部材3、導電性ブリッジ材4、被覆リード線5とこれ
らを固着するシール材8a,8bとから主に構成され
る。また、イオン感応部材3はその側面が傾斜すること
によってテーパー形状となっており、支持体2の内壁面
との間には断面楔状のシール材の滞留部9が形成されて
いる。さらに、イオン感応部材3の内側(被測定液と接
しない側)には内部電極として導電性ブリッジ材4を介
してリード線の芯線5aが接続されている。支持体2と
イオン感応部材3とは、その固着面から滞留部9に達す
るまでの部分がシール材8aによって固着され、また、
支持体の他端面においてリード線5の中途部分の外周面
がシール材8bによって固着されている。Embodiments of the present invention will be described below with reference to the drawings. [Embodiment 1] A sectional view of an ion electrode of the present invention according to Embodiment 1 is shown in FIG. The ion electrode 1 is mainly composed of a support 2, an ion sensitive member 3, a conductive bridge material 4, a coated lead wire 5 and sealing materials 8a and 8b for fixing these. Further, the ion sensitive member 3 has a taper shape due to its side surface being inclined, and a retaining portion 9 of a sealing material having a wedge-shaped cross section is formed between the ion sensitive member 3 and the inner wall surface of the support 2. Further, the core wire 5a of the lead wire is connected to the inside of the ion sensitive member 3 (on the side not contacting the liquid to be measured) via the conductive bridge material 4 as an internal electrode. The support 2 and the ion-sensitive member 3 are fixed by the sealing material 8a from the fixing surface to the retention portion 9, and
On the other end surface of the support body, the outer peripheral surface of the lead wire 5 in the middle thereof is fixed by a sealing material 8b.
【0019】上記のイオン電極1は次のようにして作製
される。イオン感応部材3である固体電解質として、外
径2.8mm×長さ4mmの円柱状のナシコンセラミッ
クス(Na3Zr2Si2PO12)の緻密質焼結体を用意
する。そして、その側面を旋盤加工により中心軸線に対
して30度の角度の傾斜面となるように加工する。この
実施例では、全側面のうち中心軸方向の一部にのみ傾斜
面を設けたが、側面全体を傾斜させてもよい。得られた
テーパー形状のイオン感応部材3の二端面のうち、径の
大きい側を被検液と接する検知面3aとし、径の小さい
側を内部電極と接する電極側面3bとして用いる。The above-mentioned ion electrode 1 is manufactured as follows. As the solid electrolyte that is the ion sensitive member 3, a dense sintered body of cylindrical Nasicon ceramics (Na 3 Zr 2 Si 2 PO 12 ) having an outer diameter of 2.8 mm and a length of 4 mm is prepared. Then, the side surface is processed by lathe processing so as to be an inclined surface having an angle of 30 degrees with respect to the central axis. In this embodiment, the inclined surface is provided only on a part of the entire side surface in the central axis direction, but the entire side surface may be inclined. Of the two end faces of the obtained tapered ion-sensitive member 3, the larger diameter side is used as the detection surface 3a in contact with the test liquid, and the smaller diameter side is used as the electrode side surface 3b in contact with the internal electrode.
【0020】次いで、導電性ブリッジ材4として、フェ
ノール樹脂にカーボン粒子を含有させてなる導電性ペー
スト(ドータイト:FC−403R,藤倉化成(株)
製)を用意し、前記イオン感応部材3の電極側面3bに
一定量を塗布する。そして、端部の被覆チューブ約1m
mを剥離して芯線を露出させたリード線5の芯線部分5
aを前記導電性ペースト中に埋入し、その状態を保持し
つつ150℃で30分間の加熱処理を行ない前記導電性
ペーストを熱硬化させて、イオン感応部材3とリード線
5とを導電性ブリッジ材4を介して接着させる。Next, as the conductive bridge material 4, a conductive paste made of phenol resin containing carbon particles (Dotite: FC-403R, Fujikura Kasei Co., Ltd.).
Manufactured), and a predetermined amount is applied to the electrode side surface 3b of the ion sensitive member 3. And the coating tube at the end is about 1m
The core wire portion 5 of the lead wire 5 in which m is peeled off to expose the core wire
a is embedded in the conductive paste, and while maintaining the state, heat treatment is performed at 150 ° C. for 30 minutes to thermally cure the conductive paste to make the ion sensitive member 3 and the lead wire 5 conductive. Bonding is performed via the bridge member 4.
【0021】次に、外径5mm×内径3mm×長さ10
mmのパイレックスガラス管よりなる支持体2の一端部
2aに上記イオン感応部材3をその検知面3aを外側に
向けて挿入する。このとき、固着部となるイオン感応部
材3の側面と支持体2の内壁面との間の固着面間隔が内
部電極側が次第に大きくなる形となり、断面楔状のシー
ル材の滞留部9が形成される。ここにエポキシ樹脂系接
着剤(粘度:50Pa・s)からなるシール材8aを注
入すると、固着面の狭小部分に入りきらない過剰のシー
ル材が滞留部9内に溜まる。この状態で加熱処理してエ
ポキシ樹脂系接着剤を硬化させ、支持体2とイオン感応
部材3とを固着する。さらに、リード線の固定と支持体
内部への水分等の浸入防止を目的として、支持体2の他
端部2bにおいてリード線5をエポキシ樹脂系接着剤か
らなるシール材8bによって固着して、イオン電極1が
得られる。Next, the outer diameter is 5 mm, the inner diameter is 3 mm, and the length is 10.
The ion sensitive member 3 is inserted into the one end portion 2a of the support body 2 made of a Pyrex glass tube of mm with the detection surface 3a thereof facing outward. At this time, the fixed surface distance between the side surface of the ion sensitive member 3 serving as the fixed portion and the inner wall surface of the support body 2 becomes gradually larger on the internal electrode side, and the retention portion 9 of the sealing material having a wedge-shaped cross section is formed. . When the sealing material 8a made of an epoxy resin adhesive (viscosity: 50 Pa · s) is injected into this, an excessive amount of the sealing material that does not fit into the narrow portion of the fixing surface is accumulated in the retention portion 9. In this state, heat treatment is performed to cure the epoxy resin-based adhesive and fix the support 2 and the ion sensitive member 3. Further, for the purpose of fixing the lead wire and preventing the intrusion of water or the like into the inside of the support, the lead wire 5 is fixed to the other end 2b of the support 2 by a sealing material 8b made of an epoxy resin adhesive, and the ion The electrode 1 is obtained.
【0022】こうして得られたイオン電極を10本用意
し、応答時間、検出電位の再現性、個体間のばらつき、
イオン濃度勾配について評価した。イオン濃度の測定は
通常のイオン電極法に基づいた方法で行ない、市販の参
照電極との電位差をエレクトロメーターを用いて温度2
5℃で測定した。被測定液として、ナトリウムイオン濃
度10mM、1000mMに調製されたTris−HC
l緩衝溶液(pH=7)を用いた。応答時間は、イオン
電極を被測定液中に浸してから検出電位が一定値を示す
までの時間を用いた。検出電位の再現性は、1本の電極
について一定のイオン濃度の被測定液での測定を5回繰
り返して行ない、その検出電位の中心値からのシフト量
を用いた。個体間のばらつきは、同一条件での10本の
電極を測定した場合の差(最大−最小)を用いた。イオ
ン濃度勾配は、濃度10〜1000mMにおける検出電
位から作成した検量線からその勾配を算出した。イオン
感応部材にテーパー加工を施さずに円柱状のままで作製
したイオン電極を比較例として用意し、その評価結果を
併せて表1に示す。Ten ion electrodes thus obtained were prepared, and the response time, reproducibility of detected potential, variation among individuals,
The ion concentration gradient was evaluated. The ion concentration is measured by a method based on a normal ion electrode method, and the potential difference from a commercially available reference electrode is measured with an electrometer at a temperature of 2
It was measured at 5 ° C. Tris-HC adjusted to have a sodium ion concentration of 10 mM and 1000 mM as a liquid to be measured
1 buffer solution (pH = 7) was used. As the response time, the time from the immersion of the ion electrode in the liquid to be measured until the detected potential shows a constant value was used. The reproducibility of the detection potential was obtained by repeating measurement with a solution to be measured having a constant ion concentration five times for one electrode, and using the shift amount from the center value of the detection potential. As the variation between individuals, the difference (maximum-minimum) when 10 electrodes were measured under the same conditions was used. The ion concentration gradient was calculated from a calibration curve prepared from the detection potential at a concentration of 10 to 1000 mM. As a comparative example, an ion electrode manufactured in a cylindrical shape without tapering the ion sensitive member was prepared, and the evaluation results are also shown in Table 1.
【0023】[0023]
【表1】 [Table 1]
【0024】この結果から明らかなように、本発明のイ
オン電極は、応答時間が比較例のものの約5分の1以下
に短縮され、再現性及び個体間のばらつきについても従
来品に比べて著しく改善されていることが判明した。ま
た、イオン濃度勾配に関しても比較例と遜色はなく、む
しろ若干理論勾配値に近い値が得られた。As is clear from these results, the ion electrode of the present invention has a response time reduced to about one-fifth or less of that of the comparative example, and reproducibility and variation among individuals are remarkably higher than those of the conventional products. It turned out to have been improved. Also, the ion concentration gradient was comparable to that of the comparative example, and rather a value slightly closer to the theoretical gradient value was obtained.
【0025】〔実施例2〜6〕次に、本発明のイオン電
極の他の構造例を示すが、いずれも実施例1と同様の測
定性能が得られた。実施例2のイオン電極21は、イオ
ン感応部材3は円柱形状とし、該イオン感応部材3が固
着されるべき支持体2の内壁面の一部に奥広がりの傾斜
面(傾斜角度30度)を設けたこと以外は実施例1とほ
ぼ同じようにして作製したイオン電極の例であり、その
断面図を図2に示す。[Examples 2 to 6] Next, other structural examples of the ion electrode of the present invention will be shown. In all cases, the same measurement performance as in Example 1 was obtained. In the ion electrode 21 of the second embodiment, the ion sensitive member 3 has a cylindrical shape, and an inclined surface (inclination angle of 30 degrees) is formed on a part of the inner wall surface of the support 2 to which the ion sensitive member 3 is to be fixed. This is an example of an ion electrode manufactured in substantially the same manner as in Example 1 except that it is provided, and its cross-sectional view is shown in FIG.
【0026】実施例3〜6は平板型のイオン電極の例で
あり、その断面図を図3〜図6に示す。実施例3のイオ
ン電極31は、イオン感応部材3として直径10mm×
厚さ2mmの円板状のナシコンセラミックス焼結体を用
い、その側面全周を角度45度にて面取りし、径の小さ
い側の底面を検知面3aとし、他の面を電極側面3bと
して用いたものである。実施例1と同様にして電極側面
3bに導電性ブリッジ材4を介してリード線5が接続さ
れている。支持体2には、20mm×20mm×厚さ1
mmのα−アルミナ質焼結体板を使用し、そのほぼ中央
部に直径約3mmの貫通孔11が設けられている。この
貫通孔11に検知面3aを合わせ、シール材8a(エポ
キシ樹脂系接着剤)を用いて、貫通孔11の周縁部から
滞留部9までの部分が固着されている(図3)。このよ
うな平板型のイオン電極は、少量の被測定液をサンプリ
ングしてコンタミネーションの恐れのない滴下式の測定
をするのに適する他、複雑な形状物の表面に密着させた
ままリアルタイムで測定をするのにも適している。Examples 3 to 6 are examples of flat plate type ion electrodes, and cross-sectional views thereof are shown in FIGS. 3 to 6. The ion electrode 31 of Example 3 has a diameter of 10 mm × as the ion sensitive member 3.
A disc-shaped NASICON ceramics sintered body with a thickness of 2 mm was used, and the entire side surface was chamfered at an angle of 45 degrees. Used. Similar to the first embodiment, the lead wire 5 is connected to the electrode side surface 3b through the conductive bridge material 4. The support 2 has 20 mm x 20 mm x 1 thickness
An .alpha.-alumina sintered body plate having a diameter of 3 mm is used, and a through hole 11 having a diameter of about 3 mm is provided at a substantially central portion thereof. The detection surface 3a is aligned with the through hole 11, and a portion from the peripheral portion of the through hole 11 to the retention portion 9 is fixed by using a sealing material 8a (epoxy resin adhesive) (FIG. 3). Such a flat plate-type ion electrode is suitable for performing a drop-type measurement in which a small amount of liquid to be measured is sampled and there is no risk of contamination. It is also suitable for
【0027】実施例4のイオン電極41は、図4に示し
たように、実施例3で用いた円板状のイオン感応部材3
は面取りすることなくそのまま用い、支持体2の貫通孔
11の周縁部に傾斜面を形成して組み合わせた例であ
る。実施例5のイオン電極51は、図5に示したよう
に、前記の円板状のイオン感応部材3の電極側面に傾斜
壁面をもつ凹部を形成し、該凹部の底部に内部電極を接
続した後、これを支持体2の外側面(被検液側)に固着
した例である。実施例6のイオン電極61は、図6に示
したように、前記の円板状のイオン感応部材3をそのま
ま用い、支持体2の貫通孔11の周縁を面取りして傾斜
面を形成して組み合わせた例である。実施例5,6のよ
うに支持体2の外側にイオン感応部材3が突出したタイ
プの電極では、検知面3aと被検液との接触が容易とな
る利点がある。As shown in FIG. 4, the ion electrode 41 of the fourth embodiment is a disk-shaped ion sensitive member 3 used in the third embodiment.
Is an example in which a chamfer is used as it is, and an inclined surface is formed at the peripheral edge portion of the through hole 11 of the support body 2 in combination. In the ion electrode 51 of Example 5, as shown in FIG. 5, a recess having an inclined wall surface was formed on the electrode side surface of the disk-shaped ion sensitive member 3, and the internal electrode was connected to the bottom of the recess. This is an example in which this is subsequently fixed to the outer surface of the support body 2 (the side of the test liquid). As shown in FIG. 6, the ion electrode 61 of Example 6 uses the disk-shaped ion sensitive member 3 as it is, and chamfers the peripheral edge of the through hole 11 of the support 2 to form an inclined surface. This is an example of combination. The electrode of the type in which the ion sensitive member 3 is projected to the outside of the support 2 as in Examples 5 and 6 has an advantage that the detection surface 3a and the test liquid can be easily brought into contact with each other.
【0028】[0028]
【発明の効果】本発明のイオン電極は、上記の構成とす
ることにより、イオン感応部材と支持体との固着用シー
ル材が内部電極に接触することがないため、シール材等
に起因する電位への影響(ノイズの発生や応答時間の遅
延等)が抑えられる。EFFECTS OF THE INVENTION With the ion electrode of the present invention having the above-mentioned structure, the sealing material for fixing the ion sensitive member and the support does not come into contact with the internal electrode. The influence (noise occurrence, delay of response time, etc.) on the
【0029】その結果、 応答時間(検出電位が安定化するまでの時間)が短縮
され、 検出電位の再現性が向上し、 電極間の検出電位の個体差(ばらつき)が低減され、 検出電位のイオン濃度勾配がネルンスト則の理論値
(59.2mV/decade:25℃)に近似した高
い測定精度を有する全固体型のイオン電極が、 簡便なシール材固着作業によって得られるという効果
を奏する。As a result, the response time (the time until the detection potential stabilizes) is shortened, the reproducibility of the detection potential is improved, the individual difference (variation) in the detection potential between the electrodes is reduced, and the detection potential An all-solid-state type ion electrode having a high measurement accuracy in which the ion concentration gradient is close to the theoretical value of the Nernst law (59.2 mV / decade: 25 ° C.) can be obtained by a simple sticking operation of the sealing material.
【図1】 実施例1に係る本発明のイオン電極の断面
図。FIG. 1 is a sectional view of an ion electrode of the present invention according to a first embodiment.
【図2】 実施例2に係る本発明のイオン電極の断面
図。FIG. 2 is a sectional view of an ion electrode of the present invention according to a second embodiment.
【図3】 実施例3に係る本発明のイオン電極の断面
図。FIG. 3 is a sectional view of an ion electrode of the present invention according to a third embodiment.
【図4】 実施例4に係る本発明のイオン電極の断面
図。FIG. 4 is a sectional view of an ion electrode of the present invention according to a fourth embodiment.
【図5】 実施例5に係る本発明のイオン電極の断面
図。5 is a sectional view of an ion electrode of the present invention according to Example 5. FIG.
【図6】 実施例6に係る本発明のイオン電極の断面
図。FIG. 6 is a sectional view of an ion electrode of the present invention according to a sixth embodiment.
1 イオン電極 2 支持体 3 イオン感応部材 4 導電性ブリッジ材 5 リード線 8a,8b シール材 9 滞留部 11 貫通孔 1 Ion Electrode 2 Support 3 Ion Sensitive Member 4 Conductive Bridge Material 5 Lead Wires 8a, 8b Sealing Material 9 Retaining Part 11 Through Hole
Claims (9)
該イオン感応部材上に配置された内部電極と、前記イオ
ン感応部材の検知面と前記内部電極とを仕切るべくシー
ル材で固着されてなる支持体とを備え、前記イオン感応
部材と支持体との固着面間隔が内部電極側が次第に大き
くなるように設けられていることを特徴とするイオン電
極。1. An ion sensitive member comprising a solid electrolyte,
An ion-sensitive member disposed on the ion-sensitive member; and a support body fixed by a sealing material to separate the detection surface of the ion-sensitive member from the internal electrode. An ion electrode, wherein the fixed surface spacing is provided such that it gradually increases on the internal electrode side.
ーパーが設けられていることを特徴とする請求項1に記
載のイオン電極。2. The ion electrode according to claim 1, wherein the ion sensitive member is provided with a chamfer, a roundness or a taper.
設けられていることを特徴とする請求項1に記載のイオ
ン電極。3. The ion electrode according to claim 1, wherein the support is chamfered, rounded or tapered.
す角度が10〜80度であることを特徴とする請求項1
ないし3のいずれかに記載のイオン電極。4. The angle formed by the fixing surface between the ion sensitive member and the support is 10 to 80 degrees.
The ion electrode according to any one of 1 to 3.
からなることを特徴とする請求項1ないし4のいずれか
に記載のイオン電極。5. The ion electrode according to claim 1, wherein the solid electrolyte is made of ion conductive ceramics.
該イオン感応部材上に配置された内部電極と、前記イオ
ン感応部材の検知面と前記内部電極とを仕切るべく固着
されてなる支持体とを備えたイオン電極の製造方法にお
いて、前記イオン感応部材と支持体とをその固着面間隔
が内部電極側が次第に大きくなるように配置し、液状ま
たはペースト状のシール材を注入した後、これを硬化さ
せてイオン感応部材と支持体とを固着する工程を有する
ことを特徴とするイオン電極の製造方法。6. An ion-sensitive member comprising a solid electrolyte,
A method for producing an ion electrode, comprising: an internal electrode disposed on the ion-sensitive member; and a support body fixed to separate the detection surface of the ion-sensitive member and the internal electrode, wherein the ion-sensitive member comprises: There is a step of arranging the supporting body so that the fixing surface distance becomes gradually larger on the internal electrode side, injecting a liquid or paste-like sealing material, and then curing the sealing material to fix the ion-sensitive member and the supporting body. A method for manufacturing an ion electrode, comprising:
700Pa・sであることを特徴とする請求項6に記載
のイオン電極の製造方法。7. The viscosity of the sealing material at 25 ° C. is 10 to 10.
It is 700 Pa.s, The manufacturing method of the ion electrode of Claim 6 characterized by the above-mentioned.
丸みが形成され、またはテーパー形状であることを特徴
とする請求項6または7に記載のイオン電極の製造方
法。8. The method for producing an ion electrode according to claim 6, wherein the ion sensitive member has chamfers or rounded corners or has a tapered shape.
からなることを特徴とする請求項6ないし8のいずれか
に記載のイオン電極の製造方法。9. The method for producing an ion electrode according to claim 6, wherein the solid electrolyte is made of ion conductive ceramics.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP7291848A JPH09105734A (en) | 1995-10-12 | 1995-10-12 | Ion electrode and its manufacture |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP7291848A JPH09105734A (en) | 1995-10-12 | 1995-10-12 | Ion electrode and its manufacture |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH09105734A true JPH09105734A (en) | 1997-04-22 |
Family
ID=17774207
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP7291848A Pending JPH09105734A (en) | 1995-10-12 | 1995-10-12 | Ion electrode and its manufacture |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH09105734A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103094027A (en) * | 2011-10-31 | 2013-05-08 | 日新离子机器株式会社 | Extraction electrode system and slit electrodes |
-
1995
- 1995-10-12 JP JP7291848A patent/JPH09105734A/en active Pending
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103094027A (en) * | 2011-10-31 | 2013-05-08 | 日新离子机器株式会社 | Extraction electrode system and slit electrodes |
KR101366512B1 (en) * | 2011-10-31 | 2014-02-24 | 닛신 이온기기 가부시기가이샤 | Extraction electrode system and slit electrodes |
CN103094027B (en) * | 2011-10-31 | 2015-11-11 | 日新离子机器株式会社 | Extraction electrode system and gap electrode |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN107037107B (en) | Electric potential sensor | |
Vonau et al. | pH monitoring: a review | |
US4753719A (en) | Ion sensor and method of manufacturing same | |
CN104422720B (en) | Measuring device | |
CN109752435B (en) | Half cell for measuring pH value, method for manufacturing half cell, and potential sensor | |
Kakutani et al. | Ion-transfer voltammetry and potentiometry of acetylcholine with the interface between polymer-nitrobenzene gel and water | |
US4495052A (en) | Replaceable junctions for reference electrodes | |
JP2698808B2 (en) | Ion sensor | |
JPH09105734A (en) | Ion electrode and its manufacture | |
Vonau et al. | Potentiometric all solid-state pH glass sensors | |
KR20190072451A (en) | Electrode for potential detection of electromagnetic flowmeter | |
JPH07325065A (en) | Ion electrode | |
US4495053A (en) | Replaceable junctions for reference electrodes | |
JPH09178690A (en) | Ion sensor and method for measuring ion concentration | |
JPH0815212A (en) | Ion electrode | |
US20060091009A1 (en) | Ion selective electrode with integral sealing surface | |
US5393402A (en) | Electrode with crystal membrane | |
CN112567237A (en) | Potentiometric measuring chain and method for determining pH value | |
JPH10197474A (en) | Reference electrode for electrochemical detector | |
JPS6243557A (en) | Solid electrode for electrochemical sensor | |
GB2089997A (en) | Replaceable junctions for reference electrodes | |
CN112083051B (en) | Ion selective electrode and electrochemical sensor | |
JPH0244203Y2 (en) | ||
JPS59214751A (en) | Collation electrode | |
JPH0439568Y2 (en) |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20040622 |