JPS6232350A - Production of ion electrode - Google Patents

Abstract

PURPOSE:To produce an ion electrode having good reproducibility by packing a pasty compsn. for an ion carrier film between the periphery of an internal sensitive electrode and the inside wall of an external tube. CONSTITUTION:The internal sensitive electrode 10 which is coated with an oxidation-reduction film 4 on the end face at the front end thereof and is coated with an insulating layer 5 on the periphery except said end face is preliminarily manufactured. The film 4 part at the top end of a base body 1 is then inserted into the external tube 6 so as to be positioned at the prescribed distance (d) beyond the top end of the tube 6. A recess (s) is thereby formed between the top end of the base body 1 and the top end of the tube 6. The pasty compsn. of the ion carrier films is packed into the recess (s) and is cured to form the ion carrier film 7 having a desired film thickness. The possibility for the variance of the product or leakage is thus eliminated and the easy and quick production of the ion electrode having the good stability in the characteristics and reproducibility is made possible.

Description

[Detailed Description of the Invention] ■ Background of the Invention [Technical Field] The present invention relates to an ion electrode having a solid-state structure, which is coated with an ion carrier membrane that selectively transports target ions to a substrate having an oxidizing ring element reaction function. Regarding the manufacturing method.

[Prior art]

One method for producing ion electrodes is to apply an ion carrier film to a +4-pole substrate made of platinum or silver using a dipping method.
In this method, it is difficult to adjust the viscosity of the dipping solution, dipping and pulling speed, or drying conditions.For example, if the viscosity of the dipping solution is low, it will take a long time to form a desired film thickness, and if the viscosity of the dipping solution is increased, it will take a long time. There are problems such as the tendency to trap air bubbles. Further, the conventional ion electrode obtained in this manner has a problem in that accurate measurement values cannot be obtained when the partial pressure of O2 or CO2 dissolved in the measurement liquid changes.

■Purpose of the Invention The present invention provides a method for manufacturing an ion electrode, which allows an internal sensitive electrode having an oxidation ring reaction function to be coated with an ion carrier film of any given thickness in a simple process with good reproducibility. With the goal.

Furthermore, this invention prevents leakage of the measurement liquid to the internal sensitive electrode (
An object of the present invention is to provide a method for manufacturing an ion electrode that can prevent leakage.

■ Summary of the Invention That is, the present invention consists of an internally sensitive W pole whose base end is connected to the REET 9 wire and whose circumferential surface is covered with an insulating layer except for the distal end. inserting and holding the electrode in a state where the tip of the electrode is flush with the tip of the sheathing tube or a predetermined distance inward from the tip of the sheathing tube; in this situation, the ion carrier substance and A step of directly contacting the tip of the internal sensitive electrode and the tip of the exterior tube with a paste-like ion carrier film composition containing a paste-like synthetic resin that has the property of curling with the exterior tube and has good adhesion to the exterior tube. and curing the tested paste-like ion carrier film composition.

Furthermore, the present invention provides a method for manufacturing the above-mentioned 4-piece ion, including the internal sensitive electric current ffl tip and the exterior tip.

- Provides a method characterized in that the paste-like ion carrier film composition is filled not only in the gap between the tip of the plate but also between the periphery of the internal sensitive i-electrode and the inner wall of the outer tube. It is.

Furthermore, the present invention provides the method for manufacturing an ion electrode, wherein the outer coverings -f are made of synthetic resin, and the inner walls thereof are surface-treated to improve adhesion before being filled with the paste-like synthetic resin. The present invention provides a method characterized by the following.

■ Detailed description of the invention The present invention will be described below with reference to illustrated embodiments.

1 to 3 show the manufacturing process of the ion electrode according to the first embodiment of the present invention.
As shown in the figure, as an internal sensitive electrode 10, an IJ (I wire 3) is connected to the base end of a cylindrical graphite substrate 1 via a conductive adhesive 2 such as solder or a silver compound, and a carbon dioxide film is applied to the tip end surface. 4 and the surrounding surface except for the end surface is covered with an insulating layer 5, and as shown in FIG. Insert and hold the oxidation-reduction film 4 so that it is positioned a predetermined distance (indicated by @d'' in the figure) from the tip of the exterior tube 6. This allows the tip of the base 1 and the tip of the exterior tube 6 to connect. A recess @S# is formed between the recesses.Next, as shown in FIG. , and then the filling material 6r is formed by heat treatment or the like to form an ion carrier film 7, thereby completing the ion process.

In the above embodiment, the main body of the internal sensitive electrode IQ was described as a graphite base 1 whose tip end surface was coated with a redox film 4. , platinum electrode, silver electrode,・
You may use a maternal cavity electrode etc. as appropriate.
The material of the A-edge layer 5 is an insulating material such as a thermoplastic resin or a thermosetting resin, and is formed by appropriately coating one peripheral surface of the base body by a dipping method or the like.

It is preferable that the external packagings -f6 have a high bonding property with the proton carrier membrane 7 in order to prevent the measurement liquid from leaking into the sensing portion of the substrate 1.

Therefore, the material of the outer layer should be selected to have the same or almost the same or similar properties as the material of the proton carrier membrane 7, or the inner surface should be treated with plasma discharge.
By physical treatment such as sputtering, or by strong acid,
It is preferable to improve the adhesion with the proton carrier membrane 7 by modifying it by chemical treatment such as strong alkali or metal (IJ) treatment or graft polymerization.

Distance between the tip of the base 1 and the synthetic resin tip
"d" regulates the thickness of the proton carrier film formed on the tip end surface of the base 1, and the thickness of the proton carrier film can be increased or decreased by increasing or decreasing the distance "d".

The thickness of the proton carrier membrane 7 is generally 50 μm to 3 μm.
Since the distance "d" is selected within the range of m, the distance "d" is also adjusted approximately within this range.

The ion carrier membrane 7 may be made of conventionally known ion carrier materials such as dodecylamine, octaphenylcyclotetrasilane, and others.

Cod, Na'', c, 2+, ct2-, etc., can be arbitrarily selected from those containing a carrier material for the desired ions, an electrolyte, and a curable paste resin that can disperse and support these. It is preferable to use a non-foaming material that shows little change over time.

The method of curing the ion carrier composition is not limited to the heating method described above, but also other physical methods such as light, electron@
Alternatively, a chemical method such as using a crosslinking agent may be used.

FIG. 4 shows another second embodiment of the present invention, in which an insulating inner tube 11 (
For example, a synthetic resin tube such as a Teflon tube is used, and other than that, the manufacturing and structure are the same as in the first embodiment. Therefore, the same parts as those in the first embodiment are given the same reference numerals, and the explanation thereof will be omitted.

The polymerization of this second example is absolutely RN! It is possible to simplify the process such that the coating thickness of I5 can be relatively thin.

FIG. 5 shows an embodiment of fJ3 according to the present invention, which is a further modification of the second embodiment, and the only difference from the second embodiment is that the inner side 11 and The diameters of each of the tubes are selected so as to form a tubular space between them and the outer shell, and this tubular space is also filled with the paste-like ion carrier film composition.

The rest is the same as in the second embodiment, and therefore, the same parts as in the second embodiment are designated by the same reference numerals and the explanation thereof will be omitted. This third
In the case of the above embodiment, an ion carrier film is also formed in the tubular space, and this covers the sensitive part of the internal sensitive electrode from the surroundings, making it possible to more effectively prevent leakage from the measurement liquid. can.

Figure 6 of Hani is a book showing a miniature example of Invention 4,
Exterior chip in the second embodiment.

- A surface modification layer 12 is formed on the surface of Zorro to improve adhesion with the ion carrier film 7.Other configurations and manufacturing methods are the same as in the second embodiment. It is. Therefore, the same parts as those in the second embodiment are given the same reference numerals, and the explanation thereof will be omitted.

In addition, in FIG. 6, the surface modified layer 12 is
Although the case where they are formed on both the inner and outer surfaces of the exteriors -f is shown, they may be formed only on the inner surface.

Production Example 1 This production example shows a production example of the ion electrode shown in Fig. 4 for hydrogen ions. First, a stainless steel rod is immersed in a dipping solution having the composition shown in Table 1 below, and then pulled up and dried. A film with a thickness of several hundred microns was formed by repeating several tens of lines, and then the stainless steel rod was removed and the inner diameter was 1.7.
■I made the exterior chuzoro.

Table 1 Composition of immersion liquid Weight % Toridofylamine 0.18tetrakis(p″″″Potassium chlorophenyl urate A O
, 11 pre-vinyl chloride (degree of polymerization 1000) 6
．． 03 Zooctyl sepacate 12.06 Tetrahydro7 run (molten fl') 81.62 Next, a lead wire (e.g. copper wire) 3 was attached to one end of the cylindrical graphite substrate (diameter 1,0 m) with conductive adhesive 2 After inserting the wire so that the non-chamfered end surface connected to the lead wire is flush with the opening of the insulating tube, insert a wire into the gap between the base 1 and the insulating tube. A resin 5 injected and solidified was prepared, and the redox film 4 was coated on the end face where the insulating layers 5 and 11 were not overlapped by C. decomposition polymerization according to the conditions shown in Table 2.

Table 2 'Ili deoxidation decomposition polymerization conditions Electrolyte composition (molar concentration) 0 to +l, Q l rut (vs 5SCE) After three runs, +1.0 kelt for 10 minutes Constant 1st position electrolysis Produced in this way The internal sensitive electrode prepared above was inserted concentrically into the exterior tube f6 prepared above, and positioned so that the distance between the end face of the oxidation-reduction film 4 and the tip of the exterior tube was 2 m, and in that state. It was fixed with.

Next, the 4-st ion carrier composition shown in Table 3 below was poured into the void @S'', and heat treated at 140°C for 1 minute.
An ion carrier film 7 having a thickness of about 21% was formed to produce a pH electrode.

Table 3 Paste-like ion carrier composition (for hydrogen ions) Weight ratio (weight f%) Tri-P decylamine 1 Tetrakis (
p-chlorophenyl)potassium borate 0.6 c/-1' Zooctyl sinate 65.6 Since the pat electrode thus obtained has the same composition as the ion carrier film 7, The bondability was extremely good, and there was no risk of leakage of the measurement liquid.

Production Example 2 As the exterior chuzoro of Production Example 1, 40 of the composition shown in Table 1 was used.
Production example 1 was used except that ethylene thiol hexafluoride, -f was immersed in a surface modifier (Tetraetch (trademark), manufactured by Junkosha) for 3 hours and then washed with ethanol and water. A pH electrode was obtained in the same manner. This pH″I
The It electrode also has an excellent characteristic of preventing leakage of the measurement liquid.Although the above example was shown for an electrode for hydrogen ions (pH electrode), by changing the ion carrier material, u% for other ions can also be obtained. It is easily understood that it can be produced by the method of the present invention.

■ Effects of the Invention According to this invention, an internal sensitive electrode is inserted into an exterior tube, and the positional relationship between the tips of both is quickly adjusted to the desired thickness of the ion carrier film, and the gap between them is The paste-like ion carrier composition is filled and cured to form the entire ion carrier film of the desired thickness.There is no risk of product variation or leakage, and the properties are stable and reproducible. Easily and easily use ion electric + pe
It is possible to quickly build Km.

[Brief explanation of drawings]

Figure 1 is a sectional view of the internal sensing electrode (Fig. 2 is a sectional view of the internal sensing electrode shown in Figure 1 inserted into the exterior cable), and Figure 3 is the configuration of Figure 2. The void formed by @
A cross-sectional view showing a state in which S' is filled with an ion carrier composition, and FIGS. 4 to 6 are cross-sectional views showing other modifications of the present invention. In the figure, 1...substrate, 2...conductive adhesive, 3...
Lead wire, 4... Oxidation-reduction film, 5... Insulating layer, 6.
・・Exterior CH・DE% 7・・Ion carrier membrane, S
...Void, 10...Internal sensitive electrode, 11...Inner side 1, -de, 12...Surface modified layer.

Claims (3)

[Claims] (1) An internal sensing electrode whose base end is connected to a lead wire and whose circumferential surface is covered with an insulating layer except for the distal end is placed inside a synthetic resin exterior tube with openings at both ends, with the tip of the electrode at the tip of the exterior tube. inserting and holding the ion carrier material so as to be located on the same plane as the outer tube or a predetermined distance inward from the tip of the outer tube; a step of coating the tip of the internal sensitive electrode with a paste-like ion carrier film composition containing a paste-like synthetic resin that has good adhesion to the outer tube, and bringing it into direct contact with the tip of the outer tube; 1. A method for producing an ion electrode, comprising the step of curing a membrane composition. (2) The pasty ion carrier film composition is filled not only in the recess between the tip of the internal sensitive electrode and the tip of the exterior tube, but also between the periphery of the internal sensitive electrode and the inner wall of the exterior tube. A method for manufacturing an ion electrode according to claim 1. (3) Claim 1, characterized in that the exterior tube is made of synthetic resin, and its inner wall has been previously subjected to surface treatment to improve adhesion before being filled with the paste-like synthetic resin. A method of manufacturing the described ion electrode.