JP3764550B2 - Small oxygen electrode and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an oxygen electrode that can be stably operated at room temperature and a method for manufacturing the same. More specifically, the present invention relates to an oxygen electrode that can be mass-produced using inexpensive materials.
[0002]
[Prior art]
The oxygen electrode can be used to produce various biosensors by immobilizing biological substances such as enzymes and microorganisms on the sensitive part. For example, if glucose oxidase is fixed to the sensitive part, a sensor for measuring glucose can be obtained, which can be used for a measuring instrument for diabetes diagnosis. Moreover, if a kind of yeast Trichosporon cutaneum is fixed to the sensitive part, a sensor for measuring a BOD value, which is one of important indicators of pollution of rivers and the like, can be made. Since the sensitive part of the Clark oxygen electrode is covered with a water-repellent gas permeable membrane, when a biosensor is configured, there is an advantage that the influence of interfering substances is less than that of various sensors.
[0003]
Thus, the oxygen electrode can be used for many applications. However, since what is currently marketed is basically made individually, it is typically about the size of a ball-point pen, and the price is also tens of thousands of yen. Therefore, when a biosensor is produced using this, it is difficult to make it disposable after one to several uses. Moreover, when applied to a biosensor, the life of a biological substance fixed to the sensitive part often becomes a problem. In the case of using a current oxygen electrode and a conventional transducer, this problem is solved by exchanging the biological material fixed membrane. However, such an operation is troublesome for the user, and it is desirable that each sensor can be made disposable. In addition, it is desirable that the size of the sensor is small.
[0004]
In order to solve such a problem, an attempt is made to miniaturize an oxygen electrode by collectively forming it on a silicon or glass substrate using a semiconductor microfabrication technique such as photolithography. However, this technology can achieve a certain price reduction and mass production of oxygen electrodes to some extent, but it is difficult to fabricate, for example, a chip of 100 yen or less as long as a normal semiconductor microfabrication technology is used. .
[0005]
[Problems to be solved by the invention]
The present invention has been made in view of the problems of the prior art as described above, and provides a small-sized oxygen electrode that can be mass-produced in a lump using an inexpensive material and has excellent responsiveness, and a method for manufacturing the same. With the goal.
[0006]
[Means for Solving the Problems]
The present inventors have found that the above problems can be solved by adopting a specific structure, and have completed the present invention.
[0007]
That is, in the oxygen electrode according to the first aspect of the present invention, a water-repellent insulating film is formed on a part of one surface of the hydrophilic porous sheet, and extends from the insulating film onto the porous sheet. A cathode pattern having a cathode and a pad with which the cathode has an electrical contact with the outside is formed, and a water-repellent insulating film is formed on a part of the opposite surface of the porous sheet. the anode and the anode so as to extend in the porous sheet anode pattern is formed to have a pad for electrical contact with the outside, the side surface and the cathode of the formed surface of the oxygen electrode to leave the pad portion Covered with an oxygen permeable material, the surface on which the anode is formed is covered with an oxygen permeable material or a plastic sheet, leaving a pad portion, and an electrode is formed in the hydrophilic porous sheet. A small oxygen electrode, wherein the liquid is impregnated.
[0008]
In the oxygen electrode of the second aspect of the present invention, a water-repellent insulating film is formed on a part of one surface of the hydrophilic porous sheet, and extends from the insulating film onto the porous sheet. A cathode pattern having a cathode and a cathode having a pad for making electrical contact with the outside, and an anode pattern having an anode and a pad for making the electrical contact with the outside are formed, and on the opposite side of the porous sheet surface is covered with a plastic sheet or insulating film on the entire surface water repellency is formed, the side surface and the cathode and the anode of the formed surface of the oxygen electrode to leave the respective pad portions coated with an oxygen permeable material The small oxygen electrode is characterized in that an electrolyte is soaked in the hydrophilic porous sheet.
[0009]
The oxygen electrode of the present invention has a minimum amount of materials necessary for its production. In the oxygen electrode of the present invention, an inexpensive material such as paper can be used as a substrate, and screen printing, spraying, or the like can be applied to pattern formation of an insulating film or the like, and the electrode can be manufactured at low cost. The oxygen electrode of the first aspect is one in which the cathode and the anode are formed on different surfaces, and the oxygen electrode of the second aspect is one in which the cathode and the anode are formed on the same surface.
[0010]
In the present invention, the porous sheet is preferably paper. Also preferably, both the cathode and the anode are silver.
The cathode pattern may have a cathode lead wire between the cathode and the pad, the cathode lead wire is sandwiched between two layers of insulating films, and an oxygen permeable material is further covered thereon. Is preferred.
[0011]
The oxygen permeable material is preferably silicone rubber.
Moreover, it is preferable that a part of the anode is in contact with the electrolytic solution and the other part is covered with an insulating film.
[0012]
Moreover, this invention provides the suitable manufacturing method of the said oxygen electrode.
That is, the manufacturing method of the 1st aspect of this invention is a manufacturing method of the small oxygen electrode including the following processes.
(1) A water-repellent insulating film is formed on both surfaces of a hydrophilic porous sheet so that a part of the porous sheet is exposed.
(2) A cathode pattern having a cathode and a pad having a pad for making an electrical contact with the outside so as to extend from the insulating film onto the porous sheet on one side, and an electrical contact between the anode and the anode on the outside An anode pattern having a pad for taking out is formed on the opposite surface.
(3) The surface on which the cathode pattern is formed is covered with an oxygen permeable material except for the pad portion, and the surface on which the anode pattern is formed is covered with an oxygen permeable material or a plastic sheet except for the pad portion. .
(4) An oxygen electrode is cut out from the obtained porous sheet, and the side surface of the oxygen electrode is covered with an oxygen permeable material.
(5) The electrolytic solution is soaked into the porous sheet from a part of the oxygen electrode .
[0013]
Moreover, the manufacturing method of the 2nd aspect of this invention is a manufacturing method of the small oxygen electrode including the following processes.
(1) A water-repellent insulating film is formed on both surfaces of a hydrophilic porous sheet obtained by cutting out and removing a part of the boundary between oxygen electrodes so that a part of the porous sheet is exposed.
(2) A cathode pattern having a cathode and a pad having a pad for making an electrical contact with the outside so as to extend from the insulating film onto the porous sheet on one side, and an electrical contact between the anode and the anode on the outside An anode pattern having a pad for taking out is formed on the opposite surface.
(3) The surface on which the cathode pattern is formed is covered with an oxygen-permeable material except for the pad portion, and the surface on which the anode pattern is formed is covered with a plastic sheet except for the pad portion.
(4) An oxygen electrode is cut out from the obtained porous sheet.
(5) The electrolytic solution is soaked into the porous sheet from a part of the oxygen electrode .
[0014]
Furthermore, the manufacturing method of the 3rd aspect of this invention is a manufacturing method of the small oxygen electrode containing the following processes.
(1) A water-repellent insulating film is formed so that a part of the hydrophilic porous sheet is exposed.
(2) A cathode pattern having a pad for the cathode and the cathode to make electrical contact with the outside so as to extend from the insulating film onto the porous sheet, and the anode and the anode make electrical contact with the outside An anode pattern having a pad is formed on the surface on which the insulating film is formed.
(3) The surface on which the cathode pattern and the anode pattern are formed is covered with an oxygen-permeable material except for the pad portion, and a water-repellent insulating film is formed on the entire surface on the opposite side, or a plastic sheet is used. Cover.
(4) An oxygen electrode is cut out from the obtained porous sheet, and the side surface of the oxygen electrode is covered with an oxygen permeable material.
(5) The electrolytic solution is soaked into the porous sheet from a part of the oxygen electrode .
[0015]
Furthermore, the manufacturing method of the 4th aspect of this invention is a manufacturing method of the small oxygen electrode containing the following processes.
(1) A water-repellent insulating film is formed on one side of a hydrophilic porous sheet obtained by cutting out and removing a part of the boundary of the oxygen electrode so as to expose a part of the porous sheet.
(2) A cathode pattern having a pad for the cathode and the cathode to make electrical contact with the outside so as to extend from the insulating film onto the porous sheet, and the anode and the anode make electrical contact with the outside An anode pattern having a pad is formed on the surface on which the insulating film is formed.
(3) The surface on which the cathode pattern and the anode pattern are formed is covered with an oxygen-permeable material except for the pad portion, and a water-repellent insulating film is formed on the entire surface on the opposite side, or a plastic sheet is used. Cover.
(4) An oxygen electrode is cut out from the obtained porous sheet.
(5) The electrolytic solution is soaked into the porous sheet from a part of the oxygen electrode .
[0016]
According to the production method of the present invention can be produced in large quantities at once oxygen electrode. In particular, according to the manufacturing methods of the second and fourth aspects, since the boundary portion of the oxygen electrode of the porous sheet is previously cut out and removed, when the oxygen electrode is cut out from the porous sheet, the porous sheet has a cross section. Is not exposed except for the pad portion, and the side surface of the oxygen electrode is covered, so that the step of covering the side surface of the oxygen electrode can be omitted.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail.
<1> Oxygen electrode of the present invention The hydrophilic porous sheet 1 used in the present invention is used for impregnating and holding an electrolytic solution, and forms an insulating film thereon with good adhesion. There is no particular limitation as long as the metal pattern to be the cathode and the anode has good adhesion. Examples of such a porous sheet 1 include filter paper and a membrane filter made of nitrocellulose. Filter paper is preferred, and commercially available ones can be used.
[0018]
The thickness of the porous sheet is usually 100 to 300 μm, and the size varies depending on the application, but is usually 0.2 to 0.5 cm × 1 to 2 cm.
The water-repellent insulating film 2 formed on the porous sheet 1 is usually composed of a water-repellent polymer, and the polymer used needs to satisfy the following conditions.
(1) The porous sheet 1 is not made water-repellent by soaking into the porous sheet 1 such as paper.
(2) Adhesion with a metal electrode pattern formed on the insulating film 2 is practically sufficient.
[0019]
Examples of such polymers include polyimide and silicone rubber.
The insulating film 2 may be formed by applying the polymer, or may be formed by bonding a sheet made of the polymer with an adhesive or the like. An example of the sheet coated with an adhesive is a tape. When a tape is used, it is necessary to satisfy the following conditions in addition to the above conditions (1) and (2).
(3) The electrolyte solution soaks into the porous sheet and does not peel off even when the tape gets wet. This condition does not need to be met perfectly, but it must be at least soaked in the user electrolyte into the porous sheet and not peeled off while using the oxygen electrode.
[0020]
The thickness of the insulating film 2 depends on the material constituting it, but is usually 50 to 100 μm.
A cathode pattern having a cathode 3 and a pad 5 for the cathode 3 to make electrical contact with the outside extends from the insulating film 2 to the porous sheet 1. That is, it exists over both. The same applies to the anode 6.
[0021]
The material constituting the cathode 3 and the anode 6 is electrically conductive and is not particularly limited as long as it does not react with the measurement solution or the like, but silver is preferably used.
The shape of the cathode pattern and the anode pattern is not particularly limited, and when the cathode 3 and the anode 6 are formed on different surfaces, it can be simply formed on the entire surface without patterning. The term “pattern” used in this specification includes such a shape formed on the entire surface. In any case, the portions in contact with the porous sheet 1 (electrolytic solution in the porous sheet) function as the cathode 3 and the anode 6. Preferably, a portion of the lead wire 4 is provided between the cathode 3 and the pad 5, and the width of the cathode 3 and the portion of the lead wire 4 is narrowed (FIG. 1B). This width is usually 0.05 to 0.2 mm.
[0022]
If the cathode 3 and the anode 6 are formed on different surfaces (the oxygen electrode of the first embodiment), the dead space can be reduced, which is advantageous in terms of layout and the pattern of the insulating film and the cathode and anode is simpler. It becomes easy to make. On the other hand, the cathode 3 and the anode 6 may be formed on the same surface (oxygen electrode of the second embodiment) (FIG. 2). In this case, the insulating layer on the back surface is formed on the entire surface so that the porous sheet is not exposed, or the entire surface is covered with a plastic sheet. Covering with a plastic sheet can be performed by adhering the sheet with an adhesive or the like. If necessary, an oxygen permeable material may be further formed as an insulating film.
[0023]
Here, the cathode lead wire 4 is insulated by being sandwiched between the insulating layer 2 and the oxygen permeable material 8, but if the insulation is insufficient with the oxygen permeable material 8 alone, It is preferable to form another insulating film on the top (FIG. 3).
[0024]
The oxygen permeable material 8 is not particularly limited, but silicone rubber is preferably used. The thickness of the layer of the oxygen permeable material 8 depends on the type, but the thickness on the cathode 3 is usually 50 to 200 μm.
[0025]
There is no restriction | limiting in particular in electrolyte solution, A suitable thing is used. For example, an aqueous potassium chloride solution can be used.
In using the oxygen electrode of the present invention, for example, a constant voltage of −1.0 V may be applied to the cathode 3 with respect to the anode 6. As a result, an oxygen reduction reaction occurs on the surface of the cathode 3, and a current value proportional to the oxygen concentration can be obtained as a signal. A reaction in which silver chloride is mainly formed proceeds on the anode side, and a stable reference potential can be obtained.
[0026]
In the oxygen electrode of the present invention, the portion where the cathode is formed is an arrangement of an oxygen permeable membrane-cathode-electrolyte layer (a porous sheet containing an electrolytic solution), and oxygen first passes through the oxygen permeable membrane, It enters the electrolyte layer, wraps around from the electrolyte layer side, reaches the cathode, and is reduced at the cathode. By adopting such a structure, it is possible to mass-produce biosensors that are small and have excellent responsiveness using inexpensive materials.
[0027]
The anode 6 is typically formed without patterning on the entire surface opposite to the surface on which the cathode 3 is formed. However, when the area ratio of the anode 6 to the cathode 3 is large, the silver chloride layer is not easily formed, and the anode potential may not be stable. In this case, as shown in FIG. 4, only a part of the anode 6 is exposed and most of the anode 6 is covered with an insulating film. The area of the exposed portion may be approximately the same as that of the cathode 3, but it is preferable to take a sufficient width A in FIG. 1B so that the reaction on the anode side does not become rate limiting. The formation of silver chloride proceeds not only to the exposed part of silver but also to the part covered with the insulating film. For this reason, the advantages of shortening the stabilization time and prolonging the service life can be achieved.
[0028]
Next, the manufacturing method of the oxygen electrode of the present invention described above will be described. In the following description, the oxygen electrode being manufactured is also referred to as a chip.
[0029]
<2> Manufacturing method of the present invention First, the manufacturing method of the first aspect of the present invention will be described step by step. For convenience of explanation, one chip is shown in the figure, but actually, a plurality of chips are collectively manufactured. For convenience of illustration, the oxygen permeable membrane 8 is omitted in FIGS. 1, 2, and 6 (a).
[0030]
(1) Formation of insulating film A water-repellent insulating film is formed on both surfaces of a hydrophilic porous sheet so that a part of the porous sheet is exposed.
[0031]
As a method of forming an insulating film so that a part of the porous sheet is exposed, (a) after masking the porous sheet, the insulating film material is applied by spraying and dried. (B) There is a method of attaching a tape as an insulating film. The mask used in the case of the method (a) does not necessarily have to be a highly accurate mask used for screen printing, and it is sufficient to cut a part of the plastic sheet. In the case of the method (b), the end portion of the tape becomes a vertically stepped portion in the pattern formation in the next step, and the pattern may not be sufficiently formed. In such a case, a pattern of a water repellent polymer (for example, silicone rubber) may be formed only in the vicinity of the step.
[0032]
(2) Formation of Cathode and Anode Pattern A cathode pattern having pads for making electrical contact with the outside of the cathode and the cathode so as to extend from the insulating film onto the porous sheet, An anode pattern having a pad for the anode to make electrical contact with the outside is formed on the opposite surface.
[0033]
The pattern can be formed by various methods such as screen printing, vacuum vapor deposition, and sputtering. From the viewpoint of cost, it is preferable to use a simple method such as screen printing.
[0034]
(3) Formation of oxygen permeable film The surface on which the cathode pattern is formed is covered with an oxygen permeable material except for the pad portion, and the surface on which the anode pattern is formed on the surface of the oxygen permeable material except for the pad portion or Cover with plastic sheet.
[0035]
When the oxygen permeable material is silicone rubber, a method of applying silicone rubber and baking for 1 hour in an atmosphere saturated with water vapor at 80 ° C. can be exemplified. In forming the film, the pad portion is protected by applying a tape that is easily peeled off. After the silicone rubber is cured, the pad portion tape is peeled off. Alternatively, as in (1), a film is formed using the mask except for the pad portion.
[0036]
The portion formed on the cathode by this coating functions as an oxygen permeable membrane.
Since the function of the oxygen permeable membrane is not required on the surface on which the anode is formed, instead of coating with an oxygen permeable material, a plastic sheet may be coated with an adhesive or the like.
[0037]
Either the cathode side surface or the anode side surface may be coated first or simultaneously.
[0038]
(4) Cutting out a chip A chip is cut out from the obtained porous sheet, and the side surface of the chip is covered with an oxygen-permeable material.
[0039]
The oxygen electrodes formed in a lump on the porous sheet are cut off with scissors or a cutter knife. At this time, since the porous sheet is exposed on the cut surface, the side surface is covered with the same oxygen-permeable material as in (3), leaving a part as the electrolyte injection port.
[0040]
(5) Injecting electrolyte into the porous sheet from a part of the chip.
Since the electrolyte injection port is provided, the electrolyte solution can be injected by immersing the entire chip in the electrolyte solution.
[0041]
Through the above steps, the oxygen electrode of the present invention can be obtained. Further, before forming the water-repellent insulating film on the hydrophilic porous sheet, a part of the portion that becomes the boundary of the chip may be cut out and removed (the manufacturing method of the second aspect) (FIG. 6). Usually, the portion that remains without being removed becomes a pad portion, which becomes the electrolyte solution injection port in the electrolyte solution injection step. Other steps are basically the same as the manufacturing method of the first aspect, but in this case, when the chip is cut out in the chip cutting step, the porous sheet is not unnecessarily exposed in the cross section. There is an advantage that the chip side surface covering step can be omitted. Further, when a plastic sheet is used, an oxygen electrode excellent in strength can be obtained.
[0042]
Moreover, when forming a cathode and an anode on the same surface, what is necessary is just to perform the process of (1)-(3) as follows in said manufacturing method.
(1) Using the hydrophilic porous sheet as it is or by cutting out and removing a part of the boundary of the chip, the surface of the porous sheet is repelled so that a part of the porous sheet is exposed. An aqueous insulating film is formed.
(2) A cathode pattern having a pad for the cathode and the cathode to make electrical contact with the outside so as to extend from the insulating film onto the porous sheet, and the anode and the anode make electrical contact with the outside An anode pattern having a pad is formed on the surface on which the insulating film is formed.
(3) The surface on which the cathode pattern and the anode pattern are formed is covered with an oxygen-permeable material except for the pad portion, and a water-repellent insulating film is formed on the entire surface on the opposite side, or a plastic sheet is used. Cover.
[0043]
【Example】
Hereinafter, the present invention will be described with reference to examples. Note that a large number of small oxygen electrodes are collectively manufactured on one sheet, but for convenience, one oxygen electrode (for one chip) is shown in the drawing.
[0044]
[Example 1]
(1) Formation of Insulating Film A water-repellent polymer is used in a state where filter paper (made by Whatman, thickness 180 μm) is used as the hydrophilic porous sheet 1 and masks are provided on both sides to expose a part of the filter paper. An insulating film 2 having a thickness of about 50 μm was formed on both sides of the filter paper by applying (drying from Universal, Plastic Dip) by spraying and drying (FIG. 1A).
[0045]
(2) Formation of cathode and anode The filter paper having the insulating film formed in (1) has portions of the cathode 3, the cathode lead wire 4 and the cathode pad 5 so as to extend on the insulating film and the filter paper. An anode pattern having a cathode pattern and anode 6 and anode pad 7 portions was formed. The cathode pattern and the anode pattern were made of silver and formed to have a thickness of 1 μm by sputtering (FIG. 1B).
[0046]
(3) Formation of oxygen permeable membrane Silicon rubber (manufactured by Shin-Etsu Chemical Co., KE4895) was applied to the surface on which the cathode 3 was formed, and baked for 1 hour in an atmosphere saturated with water vapor at 80 ° C. Next, in the same manner, the same silicone rubber was applied to the surface on which the anode 6 was formed and baked. In forming each film, the portions of the pads 5 and 7 serving as contacts when connecting to the measuring instrument were protected by applying a tape that was easily peeled off to prevent silicone rubber from sticking. After the silicone rubber on both sides was cured, the tape on the pad part was removed (FIG. 1 (c)).
[0047]
(4) Separation of chips The oxygen electrodes formed on the filter paper in a lump were separated with scissors or a cutter knife. At this time, since the filter paper was exposed on the cut surface, the same silicone rubber as used in (3) was applied to the side surface, leaving the electrolyte injection port 9 and cured.
[0048]
(5) Injection of electrolyte solution The whole chip obtained in the steps up to (4) is immersed in the electrolyte solution (potassium chloride aqueous solution), and the electrolyte solution is soaked from the portion where the filter paper is exposed, that is, the electrolyte solution inlet 9. Let
[0049]
Through the above steps, an oxygen electrode was obtained.
[0050]
[Example 2]
(1) Formation of Insulating Film A filter paper (made by Whatman, thickness 180 μm) is used as the hydrophilic porous sheet 1, and a polyimide tape (Sumitomo 3M, Kapton Film Tape No. 5413) is used as the insulating film 2 on both sides thereof. Trademark) and a thickness of 70 μm) were aligned and pasted.
[0051]
(2) Formation of cathode and anode In the same manner as in Example 1, a silver cathode pattern and an anode pattern were formed on the insulating film 2 formed in (1).
[0052]
(3) Formation of oxygen permeable membrane Silicone rubber (manufactured by Shin-Etsu Chemical Co., KE4895) was applied to the surface on which the cathode 3 was formed, and baked for 1 hour in an atmosphere saturated with water vapor at 80 ° C. Similarly, silicone rubber was applied to the surface on which the anode 6 was formed and cured. In forming each film, the pad portion to be contacted when connecting to the measuring instrument was protected from silicone rubber in the same manner as in Example 1.
[0053]
(5) Separation of chips The oxygen electrodes formed on the filter paper in a lump were separated with scissors or a cutter knife. Similar to Example 1, the same silicone rubber as in (4) was applied to the side surface, leaving the electrolyte injection port 9.
[0054]
(6) Injection of electrolyte solution The same procedure as in Example 1 was performed.
FIG. 5 shows the response when the sensitive part of the small oxygen electrode prepared by this method is immersed in an aqueous solution and an excess amount of sodium sulfite is added to remove dissolved oxygen.
[0055]
[Example 3]
(1) Formation of insulating film, cathode and anode In the same manner as in Example 1, the insulating layer 2 was formed on the filter paper, and the cathode pattern and the anode pattern were formed thereon. However, filter paper obtained by cutting out the portion near the chip boundary other than near the pad was used (FIG. 6A).
[0056]
(2) Adhesive (epoxy adhesive) 11 was spin-coated on the entire surface of a polyester sheet (thickness: 100 μm) 10 having a shape that exposes a portion of the adhesive anode pad 7 of the plastic sheet, and was immediately obtained in (1). The filter paper was bonded to the surface where the cathode 3 was not formed.
[0057]
(3) Formation of oxygen-permeable film In the same manner as in Example 2, silicone rubber serving as an oxygen-permeable film was applied to the surface on which the cathode 3 was formed except for the pad 5 portion.
[0058]
(4) Separation of chips The oxygen electrodes formed on the filter paper in a lump were separated with scissors or a cutter knife. The boundary part other than the pad part of the chip has a laminated structure of polyester sheet-adhesive-silicone rubber so that the external aqueous solution does not penetrate, so it is necessary to apply silicone rubber to the side surface. (FIG. 6 (b)).
[0059]
(5) Injection of electrolyte solution The same procedure as in Example 2 was performed. The electrolyte solution was injected from the portion of the pad where the filter paper was exposed.
[0060]
【The invention's effect】
As described above, according to the present invention, there can be provided a small oxygen electrode which can be mass-produced in a batch using an inexpensive material and has excellent responsiveness, and a method for manufacturing the same.
[Brief description of the drawings]
FIG. 1 shows a structure of a small oxygen electrode according to Examples 1 and 2 and a manufacturing method thereof.
FIG. 2 shows an example of a layout when a cathode and an anode are formed on the same surface.
FIG. 3 is a cross-sectional view of a mode in which an insulating layer for cathode lead wire is added.
FIG. 4 shows a cross-sectional view of an embodiment in which a part of the anode is exposed and the most part is covered with an insulating film.
FIG. 5 shows how the small oxygen electrode according to Example 2 responds.
6 shows the structure and manufacturing method of a small oxygen electrode according to Example 3. FIG. (A) is a top view, (b) is sectional drawing along the aa 'line of (a).
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Porous sheet 2 Insulating film 3 Cathode 4 Cathode lead wire 5 Cathode pad 6 Anode 7 Anode pad 8 Oxygen permeable film 9 Electrolyte injection port 10 Plastic sheet 11 Adhesive

Claims (11)

A pad for forming a water-repellent insulating film on a part of one surface of the hydrophilic porous sheet, and for the cathode and the cathode to make electrical contact with the outside so as to extend from the insulating film onto the porous sheet And a water repellent insulating film is formed on a part of the opposite surface of the porous sheet, and the anode and the anode extend from the insulating film onto the porous sheet. the anode pattern is formed to have a pad for electrical contact with the outside, the side surface and the cathode of the formed surface of the oxygen electrode is covered with an oxygen permeable material leaving the pad portion, which is the anode of the formed surface Is coated with an oxygen permeable material or a plastic sheet, leaving a pad portion, and an electrolyte is soaked in the hydrophilic porous sheet. Oxygen electrode. A pad for forming a water-repellent insulating film on a part of one surface of the hydrophilic porous sheet, and for the cathode and the cathode to make electrical contact with the outside so as to extend from the insulating film onto the porous sheet An anode pattern having an anode and a pad for the anode to have an electrical contact with the outside, and is a water-repellent insulating film formed on the entire opposite surface of the porous sheet? is covered with a plastic sheet, the side surface and the cathode and the anode of the formed surface of the oxygen electrode is covered with an oxygen permeable material leaving the respective pad portions, the electrolyte into the porous sheet of hydrophilic is A small oxygen electrode characterized by being soaked.   The small oxygen electrode according to claim 1 or 2, wherein the porous sheet is paper.   The small oxygen electrode according to any one of claims 1 to 3, wherein both the cathode and the anode are silver.   The cathode pattern has a cathode lead wire between the cathode and the pad, the cathode lead wire is sandwiched between two layers of insulating films, and an oxygen permeable material is further covered thereon. Item 5. The small oxygen electrode according to any one of Items 1 to 4.   The small oxygen electrode according to any one of claims 1 to 5, wherein the oxygen-permeable material is silicone rubber.   The small oxygen electrode according to any one of claims 1 to 6, wherein a part of the anode is in contact with the electrolytic solution and the other part is covered with an insulating film. The manufacturing method of the small oxygen electrode including the following processes.
(1) A water-repellent insulating film is formed on both surfaces of a hydrophilic porous sheet so that a part of the porous sheet is exposed.
(2) A cathode pattern having a cathode and a pad having a pad for making an electrical contact with the outside so as to extend from the insulating film onto the porous sheet on one side, and an electrical contact between the anode and the anode on the outside An anode pattern having a pad for taking out is formed on the opposite surface.
(3) The surface on which the cathode pattern is formed is covered with an oxygen permeable material except for the pad portion, and the surface on which the anode pattern is formed is covered with an oxygen permeable material or a plastic sheet except for the pad portion. .
(4) An oxygen electrode is cut out from the obtained porous sheet, and the side surface of the oxygen electrode is covered with an oxygen permeable material.
(5) The electrolytic solution is soaked into the porous sheet from a part of the oxygen electrode . The manufacturing method of the small oxygen electrode including the following processes.
(1) A water-repellent insulating film is formed on both surfaces of a hydrophilic porous sheet obtained by cutting out and removing a part of the boundary between oxygen electrodes so that a part of the porous sheet is exposed.
(2) A cathode pattern having a cathode and a pad having a pad for making an electrical contact with the outside so as to extend from the insulating film onto the porous sheet on one side, and an electrical contact between the anode and the anode on the outside An anode pattern having a pad for taking out is formed on the opposite surface.
(3) The surface on which the cathode pattern is formed is covered with an oxygen-permeable material except for the pad portion, and the surface on which the anode pattern is formed is covered with a plastic sheet except for the pad portion.
(4) An oxygen electrode is cut out from the obtained porous sheet.
(5) The electrolytic solution is soaked into the porous sheet from a part of the oxygen electrode . The manufacturing method of the small oxygen electrode including the following processes.
(1) A water-repellent insulating film is formed on one surface of a hydrophilic porous sheet so that a part of the porous sheet is exposed.
(2) A cathode pattern having a pad for the cathode and the cathode to make electrical contact with the outside so as to extend from the insulating film onto the porous sheet, and the anode and the anode make electrical contact with the outside An anode pattern having a pad is formed on the surface on which the insulating film is formed.
(3) The surface on which the cathode pattern and the anode pattern are formed is covered with an oxygen-permeable material except for the pad portion, and a water-repellent insulating film is formed on the entire surface on the opposite side, or a plastic sheet is used. Cover.
(4) An oxygen electrode is cut out from the obtained porous sheet, and the side surface of the oxygen electrode is covered with an oxygen permeable material.
(5) The electrolytic solution is soaked into the porous sheet from a part of the oxygen electrode . The manufacturing method of the small oxygen electrode including the following processes.
(1) A water-repellent insulating film is formed on one side of a hydrophilic porous sheet obtained by cutting out and removing a part of the boundary of the oxygen electrode so as to expose a part of the porous sheet.
(2) A cathode pattern having a pad for the cathode and the cathode to make electrical contact with the outside so as to extend from the insulating film onto the porous sheet, and the anode and the anode make electrical contact with the outside An anode pattern having a pad is formed on the surface on which the insulating film is formed.
(3) The surface on which the cathode pattern and the anode pattern are formed is covered with an oxygen-permeable material except for the pad portion, and a water-repellent insulating film is formed on the entire surface on the opposite side, or a plastic sheet is used. Cover.
(4) An oxygen electrode is cut out from the obtained porous sheet.
(5) The electrolytic solution is soaked into the porous sheet from a part of the oxygen electrode .

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