JP2019164036A - Electrode device - Google Patents

Abstract

To provide an electrode device that suppresses the manufacturing cost and to which dirt is hard to adhere.SOLUTION: An electrode device includes: an internal electrode 112; a housing storing the internal electrode; an internal liquid stored in the housing, and electrically communicating the internal electrode with a liquid junction formed in the housing or a response glass 111b forming a part of the housing or the whole thereof; and an antifouling mechanism including a light source 311 for radiating an ultraviolet ray to a sample contact surface as the surface that comes into contact with a sample of the housing, and preventing dirt from adhering to the sample contact surface of the housing. The light source is attached to the outside of the housing directly or indirectly. Alternatively, the light source is stored inside the housing.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an electrode device having an antifouling mechanism using ultraviolet rays.

  For example, when the electrochemical properties such as pH of a sample are continuously monitored for the purpose of water quality investigation, etc., electrode devices such as measurement electrodes and comparative electrodes may continue to be immersed in the sample solution for a long time. .

  Since various pollutants and microorganisms exist in the sample such as environmental water, if the sample is kept immersed in such a sample for a long time, the surface of the electrode device is contaminated, and pH measurement is performed. May adversely affect the measurement accuracy.

  Therefore, conventionally, in the electrode device as described above, for example, as shown in Patent Document 1, for the purpose of preventing the dirt from adhering to the surface of the electrode device, the dirt is decomposed on the surface in contact with the sample of the electrode device. It is considered to coat a thin film of titanium dioxide having a catalytic function.

  In order to prevent the adhesion of dirt on the surface of the electrode device by such coating, it is necessary to irradiate the thin film with ultraviolet rays that activate the catalytic function of titanium dioxide contained in the thin film.

  Therefore, conventionally, the surface of the electrode device is irradiated with ultraviolet rays from a light source provided separately from the electrode device to activate the catalytic function of the titanium dioxide coating.

  However, in the conventional electrode device as described above, the separately prepared light source must be arranged so that ultraviolet rays can be irradiated to a desired position on the surface of the electrode device, and the electrode device and the light source are installed. There is a problem that it takes time and effort.

  In addition, for example, when the electrode device is used after being immersed in a flowing sample for a long time, the position of the electrode device or the light source may be gradually changed by the flow of the sample. In addition, there is a problem that maintenance is troublesome, such as the necessity of confirming or adjusting the position of the electrode device or the light source.

Patent No. 5121012

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an electrode device that does not require time and labor for installation and maintenance, and is less likely to be contaminated on the surface.

  That is, an electrode device according to the present invention includes an internal electrode, a housing that houses the internal electrode, a liquid junction part that is housed in the housing and is formed in the housing, or one of the housings. An internal liquid that electrically connects the response glass forming part or all of the response electrode and the internal electrode, and a light source that emits ultraviolet rays to a sample contact surface that is a surface in contact with the sample of the housing. An antifouling mechanism for antifouling the contact surface, and the light source is directly or indirectly attached to the outside of the casing, or the light source is accommodated in the casing. It is a feature.

According to the electrode device configured as described above, the light source is directly or indirectly attached to the outside of the casing, or the light source is accommodated inside the casing. The trouble of preparing and installing it separately can be saved.
In addition, for example, even in a flowing sample, it is possible to reliably irradiate ultraviolet rays to a desired position of the casing without taking time and effort.

Even when ultraviolet rays do not have a thin film such as titanium dioxide, the nature of the ultraviolet rays itself can decompose organic substances that are the main cause of contamination of the electrode device or kill microorganisms. it can.
Therefore, when it is desired to reduce the manufacturing cost, an electrode device in which the surface of the casing is not coated with titanium dioxide or the like can be used.

  If the electrode device is characterized in that the case and the internal liquid have translucency, and the light source is housed in the case, the sample is difficult to transmit light. Even if it is a thing, it can irradiate to the said sample contact surface of the said housing | casing, maintaining the sufficient light intensity for the ultraviolet-ray inject | emitted from the said light source.

  If the response glass contains 40% or more of silicon dioxide, while maintaining the durability of the response glass, the UV light from the light source is efficiently transmitted to the surface on the side in contact with the sample of the response glass. The adhesion of dirt can be further suppressed.

In the case where the electrode device has a function as a reference electrode, it is conceivable to provide a liquid junction at a portion of the housing that contacts the sample.
When the liquid junction is formed of a porous material such as a small through hole formed in the housing or a ceramic disposed inside the through hole, dirt is particularly present on the liquid junction or the periphery thereof. Easy to adhere.
If dirt adheres to the liquid junction part or its periphery and the conduction between the sample and the internal liquid at the liquid junction part is interrupted, pH measurement or the like cannot be performed accurately.

  Therefore, if the light source is arranged so as to emit light in the direction of the liquid junction, the ultraviolet rays from the light source are likely to be applied to the liquid junction. Can be suppressed.

  The casing is cylindrical, the light source is disposed at a position where the liquid junction or the response glass is irradiated with ultraviolet rays, and the internal electrode is positioned relative to the position of the light source. If the internal electrode is an electrode that is easily affected by ultraviolet rays, such as a silver / silver chloride electrode, if it is disposed on the opposite side of the body from the liquid junction or the end near the response glass. Even if it exists, since the ultraviolet-ray from the said light source is hard to be irradiated to the said internal electrode, deterioration of the said internal electrode by ultraviolet irradiation can be prevented.

According to the present invention, the light source is directly or indirectly attached to the outside of the housing, or the light source is housed inside the housing, so that the light source is separately prepared and installed. This saves you time and effort.
Further, for example, even in a flowing sample, it is possible to reliably continue to irradiate the desired position of the housing with ultraviolet rays without taking time and to maintain measurement accuracy.

Even when ultraviolet rays do not have a thin film such as titanium dioxide, the nature of the ultraviolet rays itself can decompose organic substances that are the main cause of contamination of the electrode device or kill microorganisms. it can.
Therefore, when it is desired to reduce the manufacturing cost, an electrode device in which the surface of the casing is not coated with titanium dioxide or the like can be used.

The schematic diagram which shows the whole electrochemical measuring device which concerns on one Embodiment of this invention. The schematic diagram which shows the end surface of the electrode apparatus which concerns on this embodiment. The schematic diagram which shows the electrode apparatus which concerns on other embodiment of this invention. The schematic diagram which shows the electrode apparatus which concerns on other embodiment of this invention. The figure which shows the experimental result in one Example of this invention.

An embodiment of the present invention will be described below with reference to the drawings.
The electrode apparatus 1 according to the present embodiment is an electrochemical measurement apparatus 100 that measures, for example, pH, various ion concentrations, etc. in samples such as industrial wastewater and effluent water from water treatment facilities, river water, and marsh lake water. Is used.

  For example, as shown in FIG. 1, the electrochemical measurement apparatus 100 is configured to output an ion device 1 that outputs an ion concentration or the like in the sample as an electrical signal by contacting the sample as described above. Measuring device including an information processing circuit 21 that receives the output signal of the signal, converts the received output signal into desired information and outputs the information, a display unit 22 that displays the information output from the information processing circuit 21, and the like The main body 2 is provided.

  In this embodiment, as shown in FIG. 2, the electrode device 1 includes, for example, a glass electrode 11 for measuring pH and a reference electrode 12 provided so as to surround the glass electrode 11. For example, a dome-shaped composite electrode 1 having no large unevenness on its side surface.

The glass electrode 11 includes, for example, a cylindrical glass electrode casing 111 made of transparent glass or the like, and a measurement internal electrode 112 accommodated in the glass electrode casing 111.
For example, the glass electrode casing 111 is formed by integrally bonding the response glass 111b formed in a hemispherical shape to the tip of a glass electrode support tube 111a made of glass by welding or the like. It is.

The support tube glass forming the response glass 111b or the glass electrode support tube 111a may be, for example, one containing 40 mol% or more of silica. Although the silica content of the said support tube glass or the said response glass 111b should just be 40 mol% or more, it is preferable that it is 50 mol% or more, and it is more preferable if it is 60 mol% or more.
More specifically, the support tube glass or the response glass 111b contains 70 mol% of one or more substances selected from the group consisting of SiO ₂ , Al ₂ O ₃ , Li ₂ O, Na ₂ O, and K ₂ O. As mentioned above, More preferably, it contains 80 mol% or more.
The support tube glass or the response glass 111b is made of 80 mol% or more of at least one substance selected from the group consisting of SiO ₂ , Al ₂ O ₃ , alkali metal oxides, and alkaline earth metal oxides. Preferably what is contained is 90 mol% or more.
The support tube glass or the response glass 111b is made of SiO ₂ , Al ₂ O ₃ , oxide of alkali metal, oxide of alkaline earth metal, B ₂ O ₃ , oxide of lead (Pb), Y ₂ O ₃ , La ₂ O ₃ , Ta ₂ O ₅ , ZrO ₂ , TiO _2, one or more substances selected from the group consisting of 90 mol% or more, more preferably 95 mol% or more may be used.
The support tube glass or the response glass 111b is a colored substance, and the content of transition metal oxides such as chromium, manganese, iron, cobalt, nickel, and copper is 1 mol% or less, and oxides other than transition metals It is desirable that occupies 99 mol% or more.
As explained above, the support tube glass or the response glass 111b only needs to contain 95 mol% or more, more preferably 97 mol% or more of a transparent composition such as a transparent metal oxide.

  The glass electrode housing 111 contains, for example, a KCl aqueous solution or the like as the glass electrode internal solution 113 for electrically connecting the measurement internal electrode 112 and the response glass 111b.

  The measurement internal electrode 112 is, for example, a silver / silver chloride electrode, and the measurement internal electrode 112 is electrically connected to the measurement apparatus main body 2 via, for example, a lead wire L or a cable K. ing.

  The internal electrode 112 for measurement is covered with a covering material such as a sheet or a film made of a material that blocks or absorbs ultraviolet rays, for example, a resin, except for a part thereof. The covering material is not particularly limited as long as it can reduce the amount of ultraviolet rays irradiated to the measurement internal electrode 112. As for the covering method, the outer side of the measurement internal electrode 112 may be wrapped with the coating material, or the coating material may be coated on the outer side of the measurement internal electrode 112.

If the entire measurement internal electrode 112 is covered with the coating material without a gap, the electrical connection between the measurement internal electrode 112 and the glass electrode internal liquid 113 may be interrupted. For example, a cylindrical shape in which a hole or an opening for ensuring electrical continuity is formed at the distal end portion of the measurement internal electrode 112 is used.
This hole is not limited to the tip of the measurement internal electrode 112, and may be formed anywhere in the covering material as long as the measurement internal electrode 112 and the glass electrode internal liquid 113 can contact each other. .

  The comparison electrode 12 includes, for example, a cylindrical comparison electrode casing 121 made of support tube glass as described above, a comparison internal electrode 122 housed in the comparison electrode casing 121, and the comparison electrode. A through-hole formed so as to pass through the casing 121 in the thickness direction and open to the surface in contact with the sample of the comparative electrode casing 121, or a porous ceramic attached to the inside of the through-hole and the through-hole And a liquid junction portion 123 including a capillary and the like.

  In the composite electrode according to the present embodiment, the comparison electrode casing 121 is disposed so as to surround the outer periphery of the glass electrode casing 111, and the glass electrode casing 111 and the comparison electrode casing 121 are the glass electrode. The housing of the composite electrode is formed by being hermetically connected by welding or the like in the vicinity of the connection portion between the support tube 111a and the response glass 111b.

The front end side of the response glass 111 b protrudes from the front end portion of the comparison electrode casing 121.
The liquid junction 123 is formed, for example, in the vicinity of a connection portion between the glass electrode casing 111 and the comparison electrode casing 121.

The comparison internal electrode 122 is accommodated in a space formed between the inner peripheral surface of the comparison electrode casing 121 and the outer peripheral surface of the glass electrode casing 111.
Further, in the space, a transparent polymer gel containing, for example, a KCl aqueous solution, which is a comparative electrode internal liquid 124 that electrically connects the comparative internal electrode 122 and the sample via the liquid junction 123. Is housed.

  The comparison internal electrode 122 is, for example, a silver / silver chloride electrode, and the comparison internal electrode 122 is electrically connected to the measurement apparatus main body 2 via, for example, a lead wire L or a cable K. ing.

The comparison internal electrode 122 is covered with a covering material such as a sheet or a film made of resin, for example, which blocks or absorbs ultraviolet rays, similarly to the measurement internal electrode 112.
The comparative internal electrode 122 is further covered with a resin or the like that suppresses the fluidity of the comparative electrode internal liquid 124.

Thus, the composite electrode according to the present embodiment further includes an antifouling mechanism 3 that irradiates the sample contact surface, which is a surface in contact with the sample, of the comparison electrode housing 121 and the glass electrode housing 111. .
In this embodiment, the sample contact surface is, for example, the outer surface of the composite electrode housing from the tip formed of the response glass 111b of the composite electrode to a height including the entire liquid junction 123. Refers to that.

  The antifouling mechanism 3 includes, for example, a light source unit 31 and an attachment mechanism 32 that indirectly attaches the light source unit 31 to the glass electrode casing 111 or the comparison electrode casing 121.

  The light source unit 31 includes a light source 311 that emits ultraviolet light, a substrate 312 to which the light source 311 is attached, and a connection line 313 that connects the light source 311 and a power supply device (not shown).

The light source 311 is, for example, an LED chip (light emitting diode chip) that emits light having a wavelength of about 400 nm or less, more preferably 370 nm or less.
The light emitted from the light source 311 may have a wavelength of about 500 nm or less, for example, blue light having a wavelength of 500 nm or less, violet light having a wavelength of 430 or less, or the like.

In this embodiment, the ultraviolet light emitted from the light source 311 has an intensity at which light of about 8 mW / cm ² can be observed at the position of the outer surface of the response glass 111b portion of the glass electrode housing 111, for example. Is used.
More specifically, the light source 311 only needs to be capable of emitting light of 1 mM / cm ² or more and 15 mW / cm ² or less, and more preferably emit light of ² mW / cm ² or more and 12 mW / cm ^2. Anything is fine.

The substrate 312 is made of, for example, a disk-shaped ceramic.
In this embodiment, the plate surface of the substrate 312 is disposed so as to be perpendicular to the axial direction of the glass electrode housing 111, and the side of the substrate 312 near the response glass 111b is arranged. The LED chip is attached to the surface.

  For example, the light from the LED chip is emitted from the surface of the substrate 312 on which the LED chip is attached toward the end of the composite electrode housing on the side on which the response glass 111b is attached. It is.

  The attachment mechanism 32 includes, for example, a cylindrical connection line accommodating tube 321 that accommodates the connection line 313 and a coating that covers the light source unit 31 so that the light source unit 31 does not touch the glass electrode internal liquid 113. And a tube 322.

  The connection line accommodating tube 321 is, for example, a cylindrical tube made of glass or the like, and the diameter of the connection line accommodating tube 321 is smaller than the diameter of the substrate 312 in this embodiment.

  An opening on one end side of the connection line accommodating tube 321 is formed in the glass electrode casing 111 so as to protrude from the liquid surface of the glass electrode internal liquid 113 filled in the glass electrode casing 111. Has been placed.

  In this embodiment, the opening on the other end side of the connection line accommodating tube 321 is liquid-tightly joined to the surface of the substrate 312 opposite to the surface on which the light source 311 is attached.

  The cladding tube 322 is, for example, a cylindrical one made of transparent glass or the like having the same composition as the response glass or the support tube glass described above, one end is open, and the other end is, for example, It is liquid-tightly closed with a glass plate made of the same material as the side peripheral surface of the cladding tube 322.

  The cladding tube 322 is disposed so as to cover a part of the connection line accommodating tube 321, the light source 311 and the substrate 312 from the side of the substrate 312 where the light source 311 is attached.

  At this time, a space formed between the cladding tube 322, the substrate 312 and the connection line accommodating tube 321 is filled with a molding material 323 made of resin or the like, and the glass electrode internal liquid 113 is filled from the space. I try not to get in.

  In this embodiment, the light source 311 is held in the glass electrode casing 111 by holding a part of the connection line accommodating tube 321 in the cable bush B pushed and fixed inside the glass electrode casing 111. It is indirectly attached to.

  More specifically, for example, the position of the LED chip is closer to the end side of the glass electrode housing 111 opposite to the response glass 111b than the liquid junction portion 123 is. .

The manufacturing method of the composite electrode provided with such an antifouling mechanism 3 is as follows.
First, as described above, the reference electrode casing 121 is joined around the glass electrode casing 111, the glass electrode internal liquid 113 is placed inside the glass electrode casing 111, and the comparison electrode casing is also included. The body 121 is filled with the required amount of the reference electrode internal liquid 124.

  Next, the light source unit 31 to which the connection line accommodating tube 321 and the cladding tube 322 are attached from the end opposite to the end formed on the response glass 111b of the glass electrode housing 111, Insert and fix inside the glass electrode housing 111.

  The measurement internal electrode 112 is inserted between the inner peripheral surface of the glass electrode housing 111 and the connection line accommodating tube 321, and the measurement internal electrode 112 and the measurement apparatus main body 2 are connected to each other. It is attached to the housing via a lead wire L to be electrically connected, a cable bush B fixed to the opening of the glass electrode housing 111, or the like.

  The comparison internal electrode 122 is inserted between the inner peripheral surface of the comparison electrode casing 121 and the outer peripheral surface of the glass electrode casing 111, and the comparison inner electrode 122 and the measurement apparatus main body 2 Are connected to the housing via a lead wire L that is electrically connected to each other, a cable bush B fixed to an opening of the comparison electrode housing 121, or the like.

A temperature sensor T is further inserted between the inner peripheral surface of the comparison electrode casing 121 and the outer peripheral surface of the glass electrode casing 111.
The temperature sensor T, the measurement internal electrode 112, and the comparison internal electrode 122 are opposite to the end on the side where the liquid junction 123 and the response glass 111b are disposed with respect to the light source unit 31. It is an end side, and it arrange | positions so that each at least one part may be immersed in the said glass electrode internal liquid 113 or the said comparison electrode internal liquid 124.

More specifically, the temperature sensor T, the measurement internal electrode 112, and the comparison internal electrode 122, as a whole, divide the length of the glass electrode casing 111 and the comparison electrode casing 121 into two equal parts. The glass electrode housing 111 is positioned on the opposite end side of the glass electrode housing 111 from the end where the response glass 111b and the liquid junction 123 are disposed.
More preferably, the temperature sensor T, the measurement internal electrode 112, and the comparison internal electrode 122 are positions where the whole divides the length of the glass electrode casing 111 or the comparison electrode casing 121 into three equal parts. Rather than the end of the glass electrode housing 111 on which the response glass 111b and the liquid junction 123 are disposed.

According to the electrode device 1 configured as described above, the following effects can be obtained.
Cases such as the glass electrode case 111 and the comparison electrode case 121, internal solutions such as the glass electrode internal solution 113 and the comparison electrode internal solution 124, and the cladding tube 322 of the attachment mechanism 32 are made of a transparent material. As a result, the ultraviolet light emitted from the light source 311 can be efficiently transmitted to irradiate the outer surface of the housing in contact with the sample.

  Since the light source 311 is accommodated in the glass electrode casing 111, even if the sample has low light transmittance, the sample contact surface of the composite electrode casing is irradiated with sufficiently strong ultraviolet rays. can do.

  In particular, since the response glass 111b contains 40 mol% or more of silica, it is easy to transmit ultraviolet light, and it is easy to irradiate the outer surface in contact with the sample of the response glass 111b. When the content of silica is large, the durability of the glass can be improved while keeping the transmittance of ultraviolet rays high.

  The light from the LED chip is emitted to the outside from the entire surface other than the surface in contact with the substrate 312 of the LED chip, and the position where the LED chip is attached is more than the liquid junction part 123 than the response glass 111b. The sample contact surface including the entire outer surface of the response glass 111b and the entire liquid junction part 123 is irradiated with ultraviolet rays emitted from the LED chip. The whole can be irradiated.

  Since the composite electrode is of a dome shape, the surface of the glass electrode casing 111 or the comparison electrode casing 121 that is in contact with the sample does not have large irregularities, and the number of portions that are not easily irradiated with ultraviolet rays from the light source 311 is minimized. can do.

  Since the internal electrodes such as the measurement internal electrode 112 and the comparative internal electrode 122 that are silver / silver chloride electrodes are covered with a coating material that absorbs ultraviolet rays, the irradiation of the internal electrodes with ultraviolet rays is suppressed, A silvering reaction in which the silver chloride of the internal electrode is changed to silver ions can be suppressed.

Since the comparative internal electrode 122 is further covered with a resin or the like that suppresses the fluidity of the comparative electrode internal liquid 124, even if silver ions are eluted from the comparative internal electrode 122, silver ions remain in the comparative electrode. Diffusion into the internal liquid 124 can be prevented.
As a result, it is possible to further reduce the risk that silver ions are deposited at the liquid junction 123 and the conduction at the liquid junction 123 is interrupted.

  Since the light source unit 31 of the antifouling mechanism 3 includes an LED chip as the light source 311, the mounting position or the like due to the size of the light source 311 is not easily restricted, and the size of the glass electrode housing 111 is reduced. The light source unit 31 can be disposed inside the housing without being particularly large.

Since the attachment mechanism 32 includes the cladding tube 322 and the connection line accommodating tube 321, the LED chip used in the light source unit 31 and the connection line 313 for supplying power to the LED chip are connected to the glass electrode internal liquid. The glass electrode housing 111 can be placed inside the glass electrode housing 111 without being immersed in the glass 113.
As a result, it is possible to use a commercially available LED chip or the like without worrying about failure or leakage even without using a special LED chip or connection line 313 that can be used in water.

The internal electrode for measurement 112 and the internal electrode for comparison 122 are arranged on the end side opposite to the end on the side where the liquid junction portion 123 and the response glass 111b are arranged with respect to the light source unit 31. Therefore, it is possible to prevent the ultraviolet rays emitted from the light source 311 from being applied to the measurement internal electrode 112 and the comparison internal electrode 122.
As a result, the silvering reaction of the measurement internal electrode 112 and the comparative internal electrode 122 due to ultraviolet irradiation can be suppressed.

  Since the light source 311 and the measurement internal electrode 112, the comparison internal electrode 122, and the temperature sensor T are separated by a sufficient distance, even if the light source 311 generates heat, the measurement internal electrode 112, The influence of heat on the comparative internal electrode 122 and the temperature sensor T can be suppressed.

The present invention is not limited to the above embodiment.
For example, the cladding tube 322 that covers the light source unit 31 is not an essential configuration. For example, as shown in FIG. 4, the connection line accommodating tube 321 may cover the connection line 313 and the light source unit 31. .
The composite electrode is not limited to the type described above. For example, as shown in FIG. 4, the response glass 111b and the liquid junction 123 can be easily detached from the outside of the housing. An attached chip type may be used.

  In the case of such a chip type, in particular, the light source unit 31 may be detachably attached to the housing from the outside and exchangeable from the outside.

Specifically, for example, the composite electrode communicates with the inside of the glass electrode support tube 111a and the inside of the response glass 111b formed in a dome shape, for example, a response glass chip 4 made of resin, and the comparison electrode Examples include a case in which the inside of the housing 121 is a cylindrical cup that communicates with the inside of the housing 121 and includes the liquid junction portion chip 5 made of, for example, resin and having the liquid junction portion 123 formed on a part of the wall. it can.
The response glass chip 4 and the liquid junction chip 5 are attached to the end of the casing on the side in contact with the sample solution via, for example, a screwed structure.

In this modified example, the light source unit 31 including an LED chip that can be used in water as the light source 311, as with the response glass chip 4 or the liquid junction chip 5 of the casing, The light source support tube 6 is fixed to the surface of the light source support tube 6 on the side of the response glass 112b and the liquid junction portion 123, which is attached to the end of the contact side.
The light source support tube 6 corresponds to the attachment mechanism 32, and is, for example, a thin cylindrical one that can accommodate the connection line 313 therein and attach the light source 311 to the tip thereof.

In this manner, by indirectly attaching the light source unit 31 to the outside of the housing, the ultraviolet light from the light source 311 is also applied to the response glass 111b and the liquid junction 123 even in the chip-type composite electrode as described above. Can be easily irradiated.
In addition, since the light source unit 31 can be easily replaced from the outside, the light source unit 31 can be easily maintained.

  Even in the case of the chip-type composite electrode as described above, as long as the casing, the response glass chip 4, the liquid junction chip 5 and the like are transparent, for example, described in the first embodiment. Needless to say, the light source unit 31 may be disposed inside the housing.

  The light source unit 31 is not limited to the LED chip that is the light source 311 and the connection line 313 are directly connected, and the light source unit 31 may be of a wireless power feeding type.

  Specifically, the light source unit 31 may further include a wireless power feeding mechanism including a reception unit built in the LED chip and a transmission unit that wirelessly transmits power to the reception unit. it can.

  Between the receiving unit and the transmitting unit of the wireless power feeding mechanism, for example, power transmission is performed by magnetic field resonance, so the distance between the receiving unit and the transmitting unit is approximately 30 cm away, Power can be supplied to the LED chip.

Specifically, for example, an LED chip incorporating the receiving unit is placed in the glass electrode internal liquid 113 filled in the glass electrode casing 111, for example, and the transmitting unit is inserted into the glass electrode casing 111. The lead wire L connected to the measurement internal electrode 112, the comparison internal electrode 122, the temperature sensor T, or the like may be attached to the cable K side portion of the connector connected to the cable K.
In addition to this, the transmitter may be attached to a part of the connector on the housing side, or the transmitter may be attached to a part of an electrode holder for fixing the composite electrode in a sample. .

  By adopting such a wireless power supply type light source unit 31, for example, the connection line 313 does not have to be inserted into the housing of the glass electrode or the comparison electrode, so that the connection line is placed inside the housing. It is not necessary to secure a space for accommodating 313, and the housing can be made as compact as possible.

  The receiving side portion of the light source unit 31 of the wireless power feeding type that combines the LED chip, the substrate 312 and the receiving unit is, for example, a cube having a side of approximately 4.5 mm. Can be freely attached to the place.

Moreover, since it is not necessary to devise so that the connection line 313 or the like does not touch the internal liquid, the manufacture of the electrode device 1 can be simplified.
Further, since it is possible to use a wirelessly powered LED chip in the water or the like, the light source unit can be used such as floating the LED chip in the internal liquid or simply submerging in the internal liquid. The degree of freedom of the method of attaching 31 to the housing can be greatly improved.

In the above-described embodiment, the light source unit 31 is indirectly attached to the housing. However, the light source unit 31 may be directly attached to the housing.
The LED chip that is the light source 311 is not limited to the LED chip that is attached toward the end of the housing that is formed of the response glass 111b, but is directed in various directions according to the place and application where the ultraviolet light is desired. Can be attached.

  For example, the LED chip that is the light source 311 may be attached to the surface of the response glass 111b that is in contact with the glass electrode internal liquid 113 so as to face away from the tip of the response glass 111b.

  The covering tube 322, the connection line accommodating tube 321, the light source support tube 6 and the like constituting the attachment mechanism 32 may be any member that can attach the light source unit 31 to the housing, and have rigidity such as glass. It is not limited to a material made of a material, and may be made of a material having elasticity or flexibility such as rubber or string.

The glass electrode internal liquid 113 and the comparative electrode internal liquid 124 are not necessarily the same, and may be appropriately changed. These internal liquids are not limited to gels as described above, but may be liquids.
As described above, the glass electrode casing 111 is not limited to a part formed of the response glass 111b, but may be formed entirely of the response glass 111b.

The light source 311 may be attached to the comparison electrode housing 121.
The electrode device 1 does not have to be a composite electrode as described above, and the glass electrode 11 and the comparison electrode 12 may be configured as the electrode device 1 independently of each other.

The sample contact surface is a surface of the surface of the electrode device 1 that may come into contact with the sample solution and may be contaminated. As a specific example, other than those described in the above embodiment, For example, part or all of the outer surface of the composite electrode casing, part or all of the glass electrode casing, part or all of the outer surface of the response glass, part or all of the liquid junction A part or all of the outer surface of the comparative electrode casing may be included.
More specifically, the sample contact surface refers to the measurement using the composite electrode casing, the glass electrode casing 111, the entire outer surface such as the comparison electrode casing 121, the cable K of the casing, and the like. The outer surface from the tip on the side opposite to the side connected to the apparatus main body 2 to about half of its length, or three minutes of the length from the tip on the side immersed in the sample solution of these cases It refers to the outer surface up to about one.

The ultraviolet rays emitted from the light source 311 are not limited to those described above, and the outer surface of the response glass 111b is ² mW / cm ² or more which is the same intensity as the sunlight outdoors on the surface of the response glass 111b. What is necessary is just to be able to irradiate the light.
Actually, if the intensity of the ultraviolet light emitted from the light source 311 is 0.5 mW / cm 2 or more at the position of the outer surface of the response glass 111b, it can be confirmed by experiments that there is a sufficient antifouling effect. Yes.
Therefore, it is considered that a sufficient antifouling effect can be exhibited if the intensity of ultraviolet light emitted from the light source 311 is 0.5 mW / cm ² or more on the sample contact surface of the housing.
Further, depending on the conditions, the intensity of the irradiated ultraviolet rays is too strong, and the silvering reaction of the internal electrodes such as the measurement internal electrode 112 and the comparative internal electrode 122, the temperature effect on the electrochemical measurement, since there are cases where problems such as generation occurs, the intensity of ultraviolet rays irradiated on the sample contacting surface of the housing is preferably 0.5 mW / cm ² or more 3.5 mW / cm ² or less, 1.0 mW More preferably, it is not less than / cm ^{2 and not} more than 3.0 mW / cm ² .

In the embodiment, for example, the case where the sample contact surface of the casing is not coated with a thin film such as titanium dioxide has been described. However, if the sample contact surface is coated with titanium dioxide or the like, Hydroxyl radicals and superoxide radicals generated by the catalytic function can decompose a wider range of organic substances that cannot be decomposed by ultraviolet rays.
In addition, if the sample contact surface is coated with titanium dioxide, the hydrophilic effect of titanium dioxide can prevent contamination by inorganic substances.
As a result, the antifouling effect on the sample contact surface can be further improved by the synergistic effect of the ultraviolet irradiation and the catalytic effect of titanium dioxide.
By utilizing the synergistic effect of this ultraviolet ray and titanium dioxide coating, a sufficient antifouling effect can be exhibited without using a light source that emits short-wavelength ultraviolet light or high-intensity ultraviolet light as the light source.
Therefore, it is not necessary to use a light source that emits short-wavelength ultraviolet light or high-intensity ultraviolet light, and the manufacturing cost of the electrode device can be reduced more safely.

In particular, for example, in the case where irregularities are formed in the joint portion between the glass electrode casing 111 and the comparative electrode casing 121, it is considered that the ultraviolet rays from the light source are not easily irradiated to the irregular portions. It is.
As described above, the antifouling effect is further improved by applying the titanium dioxide coating to the portion where the irradiation intensity of the ultraviolet light from the light source is less than the predetermined value as described above depending on the shape of the casing. be able to.
Examples of the place where the titanium dioxide coating is applied include part or all of the sample contact surface, part or all of the outer surface of the casing, and the glass electrode casing 111 and the comparative electrode casing 121. Examples include the outer surface of the joining portion and the outer surface of the connecting portion between the glass electrode support tube 111a and the response glass 111b.

When using, for example, a KCl granule to which the reference electrode internal liquid 124 is added, the KCl granule may precipitate in the lower part of the reference electrode internal liquid 124 due to its own weight.
In such a case, the ultraviolet light emitted from the light source 311 may be dispersed by the KCl granules and may not reach the sample contact surface of the casing.

Therefore, when KCl granules are added to the internal liquid 124 of the reference electrode, the portion located between the light source 311 and the sample contact surface to which the ultraviolet light from the light source 311 is desired to be highly transparent. In addition, a polymer gel that does not mix with the polymer gel containing the KCl granule may be placed, and the polymer gel containing the KCl granule may be filled in other portions.
In order to prevent the KCl granules from being positioned between the light source 311 and the sample contact surface, for example, a liquid internal solution and a polymer gel containing KCl granules may be layered. Further, a bush, a partition plate, a partition film, or the like that can maintain electrical connection between the sample solution and the comparative internal electrode 122 may be provided inside the comparative electrode housing to adjust the position of the KCl granule.

The shape of the LED chip is not limited to a cube shape or a rectangular parallelepiped shape, but may be a polygonal column shape, a cylindrical shape, a conical shape, a pyramid shape, a hemispherical shape, a bullet shape, or the like.
The material of the housing is not limited to a material made of transparent glass, and may be made of a transparent resin. In particular, when the light source 311 is attached to the outside of the housing, The housing does not necessarily have to be transparent.

The electrode device is not limited to one that measures pH, various ion concentrations, and the like, and may be one that measures, for example, the oxidation-reduction potential of a sample or other electrochemical properties.
As the measurement internal electrode 112 and the comparison internal electrode 122, the silver / silver chloride electrode is used in the above-described embodiment. However, the present invention is not limited to this, and other components may be used depending on the application. good.
In addition, various modifications and combinations of embodiments may be performed without departing from the spirit of the present invention.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.
In this example, four composite electrodes (# 6101) manufactured by HORIBA, Ltd. were prepared, and these four composite electrodes were processed as shown in the following (a) to (d).

  (A) No processing, (b) Only with titanium dioxide coating, (c) A light source emitting ultraviolet light inside the glass electrode housing, and (d) Titanium dioxide coating With a light source attached inside the glass electrode housing.

About the composite electrode of (b) and (d), the titanium dioxide was coated 3 times by the sol-gel method to the height shown by the double arrow in FIG.
As for the composite electrodes (c) and (d), as described in detail in the first embodiment, an LED that emits light having a wavelength of about 370 nm with an intensity of about 8 mW / cm ² is placed inside the glass electrode. Attached.
In addition, the response glass used for the composite electrode used in this example, and the support tube forming the glass electrode support tube and the comparison electrode housing have the following properties.
The response glass and the support tube glass contain 80 mol% or more of one or more substances selected from the group consisting of SiO ₂ , Al ₂ O ₃ , Li ₂ O, Na ₂ O, K ₂ O, SiO ₂ , Containing 90 mol% or more of one or more substances selected from the group consisting of Al ₂ O ₃ , alkali metal oxides, alkaline earth metal oxides, SiO ₂ , Al ₂ O ₃ , alkali metal oxides, One or more selected from the group consisting of alkaline earth metal oxides, B ₂ O ₃ , lead (Pb) oxides, Y ₂ O ₃ , La ₂ O ₃ , Ta ₂ O ₅ , ZrO ₂ , TiO ₂ These substances are contained in an amount of 95 mol% or more.
The response glass and the support tube glass both have a content of transition metal oxides such as chromium, manganese, iron, cobalt, nickel, copper, etc., which are colored substances, and are oxides other than transition metals. Occupies 99 mol% or more.
The response glass and the support tube glass contain 97 mol% or more of a transparent composition such as a transparent metal oxide.

FIG. 5 shows a photograph after actually using these four composite electrodes in a chemical factory for about one month.
From the results shown in FIG. 5, in the composite electrodes (a) and (b) that do not have a light source that emits ultraviolet light, the surface in contact with the sample solution was heavily soiled.
On the other hand, in the composite electrodes (c) and (d) in which the light source that emits ultraviolet light is attached to the inside of the housing, both of the surfaces of the composite electrode housing are contaminated with the ultraviolet light. It was found that there was almost no adhesion.

From this experimental result, it was found that a composite electrode having a light source that emits ultraviolet rays inside the housing can exhibit a sufficient antifouling effect even without a titanium dioxide coating.
Since the composite electrode used in this example is of a type in which the joint between the glass electrode housing and the comparative electrode housing is constricted, ultraviolet rays from the light source housed in the glass electrode housing are used. There is a portion that is difficult to be irradiated (a portion surrounded by a circle in FIG. 5), and there was a difference in the degree of adherence of dirt with or without the titanium dioxide coating in this portion.

From the above results, it was found that when the ultraviolet ray emitted from the light source can irradiate the entire surface of the housing in contact with the sample solution, the antifouling effect can be sufficiently exhibited even without the titanium dioxide coating.
On the other hand, in the case of an electrode device having a shape where it is difficult for ultraviolet rays emitted from a light source to reach, it is considered effective to use a titanium dioxide coating in combination.

DESCRIPTION OF SYMBOLS 100 ... Electrochemical measuring apparatus 1 ... Electrode apparatus 111b ... Response glass 123 ... Liquid junction part 21 ... Information processing circuit 3 ... Antifouling mechanism 311 ... Light source

Claims (7)

An internal electrode;
A housing containing the internal electrodes;
An internal liquid that is accommodated in the housing and electrically connects the liquid crystal part formed in the housing or the response glass forming part or all of the housing and the internal electrode;
A light source for irradiating the sample contact surface, which is a surface in contact with the sample of the housing, with ultraviolet light, and an antifouling mechanism for preventing the sample contact surface of the housing
The electrode device, wherein the light source is directly or indirectly attached to the outside of the casing, or the light source is accommodated in the casing.   The electrode device according to claim 1, wherein the casing and the internal liquid have translucency, and the light source is accommodated in the casing.   The electrode device according to claim 1, wherein the light source is an LED.   The electrode device according to claim 1, wherein the response glass contains 40 mol% or more of silicon dioxide.   The electrode device according to claim 1, wherein the light source is disposed so as to emit light in the direction of the liquid junction.   The casing is cylindrical, the light source is disposed at a position where the liquid junction or the response glass is irradiated with ultraviolet rays, and the internal electrode is positioned relative to the position of the light source. The electrode device according to any one of claims 1 to 5, wherein the electrode device is disposed on an end side opposite to an end of the body on the side close to the liquid junction part or the response glass. An electrode device according to claim 1;
An electrochemical measurement device comprising: an information processing circuit that receives an output signal from the electrode device, converts the received output signal into desired information, and outputs the information.