Wettability evaluation apparatus and method

Abstract

To provide a method for evaluating wettability at a lower cost as compared with existing methods.SOLUTION: One preferred aspect of the present invention is a wettability evaluation device including: a channel into which a first medium and a second medium are introduced; a measuring instrument that measures a current value flowing in the channel when the first medium and the second medium are introduced; and a control unit that evaluates the wettability of the inner wall surface of the channel based on the current value.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a technique for evaluating wettability.

Background Art

[0002] There is a need for a technique for evaluating the wettability of a liquid. For example, an analysis apparatus for analyzing solution components is provided with a flow path pipe for feeding a sample liquid or a reagent liquid. Wettability of the flow path pipe is an important factor for appropriate liquid feeding.

[0003] For example, in an apparatus for analyzing components in blood, a change in wettability due to contamination in the flow path pipe causes liquid feeding abnormalities such as liquid residue, and sample carry-over between samples causes a decrease in analysis accuracy. Therefore, it is desired to grasp the wettability state before liquid feeding abnormalities occur between samples and to perform maintenance management to maintain an appropriate state.

[0004] As a conventional wettability evaluation technique, an evaluation method targeting flat materials or the like for the purpose of material research or the like has been developed. For example, in Patent Document 1, a method has been developed in which an individual sample plate on which a liquid is placed is vibrated, the surface tension is determined from the dynamics of the liquid during vibration, and the contact angle is obtained from the surface tension.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The technique described in Patent Document 1 has problems such as the need for an image sensor such as a camera for imaging, high implementation costs, and high analysis costs for handling time-division image data.

[0007] An object of the present invention is to provide a method for evaluating wettability at a lower cost than existing methods.

Means for Solving the Problems

[0008] A preferred aspect of the present invention is a wettability evaluation apparatus, comprising: a flow path into which a first medium and a second medium are introduced; a measuring instrument that measures a current value flowing through the flow path when the first medium and the second medium are introduced; and a control unit that evaluates the wettability of the inner wall surface of the flow path based on the current value.

[0009] Another preferred aspect of the present invention is a wettability evaluation method, including: a first step of preparing a flow path; a second step of sending a first medium and a second medium to a predetermined position of the flow path; and a third step of evaluating the movement of electric charges between a first location and a second location sandwiching the predetermined position of the flow path.

[0010] Further features related to the present disclosure will become apparent from the description in this specification and the accompanying drawings. The description in this specification is merely a typical example and does not limit the scope of the claims or the applications of the present disclosure in any way.

Advantages of the Invention

[0011] The present invention has the effect of enabling evaluation of wettability at a lower cost. Other problems, configurations, and effects than those described above will become apparent from the description of the following embodiments.

Brief Description of the Drawings

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Embodiments for Carrying Out the Invention

[0013] The embodiments will be described in detail with reference to the drawings. However, the present invention is not to be construed as being limited to the description of the embodiments shown below. Those skilled in the art can easily understand that the specific configuration can be changed without departing from the spirit or gist of the present invention.

[0014] In the configurations of the examples described below, the same reference numerals are commonly used among different drawings for the same parts or parts having similar functions, and redundant descriptions may be omitted.

[0015] When there are a plurality of elements having the same or similar functions, they may be described by attaching different subscripts to the same reference numeral. However, when it is not necessary to distinguish between the plurality of elements, the subscripts may be omitted in the description.

[0016] Expressions such as "first", "second", "third", etc. in this specification and the like are attached to identify components, and do not necessarily limit the number, order, or content thereof. Also, the numbers for identifying components are used for each context, and the numbers used in one context do not necessarily indicate the same configuration in other contexts. Further, it does not prevent a component identified by a certain number from also having the functions of a component identified by another number.

[0017] The positions, sizes, shapes, ranges, etc. of the respective components shown in the drawings and the like may not represent the actual positions, sizes, shapes, ranges, etc. in order to facilitate understanding of the invention. For this reason, the present invention is not necessarily limited to the positions, sizes, shapes, ranges, etc. disclosed in the drawings and the like.

[0018] The publications, patents, and patent applications cited in this specification constitute part of the description of this specification as they are.

[0019] Components represented in the singular form in this specification shall include the plural form unless clearly indicated otherwise in the context.

[0020] Since the technique described in Patent Document 1 requires imaging a liquid, it cannot be applied to the evaluation of the wettability of a flow path pipe whose inside cannot be observed. In an example of the technique described in the examples, as a method for evaluating the wettability inside a flow path pipe, it is applicable to a flow path whose inside cannot be observed, and as a method for keeping the mounting cost and analysis cost low, a method for evaluating the wettability inside a flow path pipe at low cost compared to existing methods using the electrical conduction characteristics of the flow path pipe when bubbles or the like are introduced into the flow path pipe as an index is provided.

[0021] A wettability evaluation apparatus of a typical embodiment is an apparatus having a flow path pipe capable of feeding a medium such as a solution, and includes a mechanism for feeding the medium to the flow path pipe, a mechanism for applying a voltage to the flow path, and a mechanism for measuring a current flowing through the flow path, and means for introducing at least two or more kinds of media into the flow path, means for measuring a current value with respect to the applied voltage when the medium is introduced, and means for evaluating the wettability of the inner wall surface of the flow path based on the current value.

[0022] The wettability evaluation apparatus according to the present disclosure provides a method for evaluating the wettability of a flow path pipe including a flow path pipe whose inside could not be observed, which was difficult in the past, at low cost, and has an effect of enabling maintenance management of the flow path pipe for performing appropriate liquid feeding.

Example

[0023] <Configuration example of wettability evaluation apparatus> FIG. 1 shows a schematic diagram of a wettability evaluation apparatus according to a first embodiment. The wettability evaluation apparatus of this example includes a measurement unit 100 and a control unit 200.

[0024] The measurement unit 100 includes flow path pipes 1a to 1e for feeding or sending air (hereinafter, feeding the medium is referred to as liquid feeding) a medium (fluid) such as a solution or a gas, and a syringe pump 2 for feeding the medium to at least a part of the flow path pipe 1. The bottle 7 stores a liquid (solution) whose wettability with the flow path pipe 1 is to be evaluated. The air filter 8 filters the gas introduced into the flow path pipe 1.

[0025] In the flow path pipe 1, three-way solenoid valves 6a and 6b and conductors 3a and 3b that can be in electrical contact with the medium in the flow path are arranged. A voltage source 4 and an ammeter 5 are electrically connected to the conductors 3a and 3b.

[0026] The controller 12 is composed of, for example, a microcomputer, and controls the operations of the syringe pump 2, the voltage source 4, the ammeter 5, the three-way solenoid valve 6, etc. However, the operation may be performed manually or may be controlled by the control unit 200.

[0027] The control unit 200 includes an analysis unit 9 that analyzes the output values from the voltage source 4 and the ammeter 5, a database 10 that stores data for calculating the relationship between the current value, voltage value, and wettability, and a display unit 11 that displays the analysis results by the analysis unit. The database 10 stores the evaluation table 700, threshold database 800, time-series data 1000, set thresholds, etc., which will be described later.

[0028] The control unit 200 can be configured by a general computer including an input device, an output device, a processing device, and a storage device. It may be configured by a single computer, or any part of the input device, output device, processing device, and storage device may be configured by other computers connected by a network.

[0029] When configuring the control unit 200 with a general computer, it includes an interface for inputting the signal from the measurement unit 100 to the input device. The output device includes the display unit 11 configured by a display monitor or the like. The database 10 is stored in a storage device such as a hard disk drive. The analysis unit 9 is configured by software and stored in a storage device such as a semiconductor memory, and is executed by a processing device such as a CPU (Central Processing Unit) to enable the processing described later.

[0030] However, the control unit 200 may be configured by a dedicated device. This form is shown in FIG. 1. In this case, the database 10 is stored in a dedicated memory (or an external database may be used), and the display unit 11 uses a dedicated image monitor. The analysis unit 9 can also implement functions equivalent to those configured by software using hardware such as an FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit). Alternatively, it may be implemented on a microcontroller.

[0031] In this device, it is possible to evaluate the wettability of the inner wall at any position of the pipe 1c between the conductors 3a and 3b. When sucking the syringe pump 2, the piping 1d side of the three-way solenoid valve 6b is opened to introduce the medium into the pipe 1c. When discharging the syringe pump, the 1e side of the three-way solenoid valve 6b is opened to discharge the medium in the syringe. The medium introduced into the pipe 1c can be switched by the three-way solenoid valve 6a. In the device of this embodiment, two media, an aqueous solution in which the electrolyte in the bottle 7 is dissolved and a gas, can be introduced.

[0032] Note that the gas can be taken in from the pipe 1b opened to the atmosphere and introduced into the pipe 1c after passing through the air filter 8. In the present embodiment device, since the influence of gravity on the surface tension of the medium with respect to the flow path pipe wall surface cannot be ignored, the inner diameter of the flow path pipe 1c is targeted to be 5 mm or less.

[0033] <Example procedure for wettability evaluation> With reference to FIG. 2, the wettability evaluation method in the device of this embodiment will be described. The flow of the evaluation method in the device shown in FIG. 1 is shown in FIG. 2. It is assumed that the controller 12 executes the process by controlling the syringe pump 2, the voltage source 4, the ammeter 5, and the three-way solenoid valve 6.

[0034] First, with the syringe pump 2, the aqueous solution (medium 1) is sent from the bottle 7 via the pipe 1a to fill the inside of the flow path pipe 1c with the aqueous solution (reference state) (S201).

[0035] After that, a predetermined voltage is applied using the voltage source 4 (S202), and the current value at that time is measured with the ammeter 5 (S203).

[0036] Next, at the position where the wettability of the flow path pipe 1c is to be evaluated, a predetermined amount of gas (medium 2) is sent from the pipe 1b with the syringe pump 2 (S204).

[0037] During this period, the current value is also measured with the ammeter 5, and the measurement is terminated after a predetermined time has elapsed (S205).

[0038] At this time, the current value during gas introduction is analyzed for its change over time since the start of gas feeding (S206) to evaluate wettability (S207).

[0039] <Example of evaluating wettability> An example of evaluating wettability using the apparatus of this embodiment will be described. Pipes with an inner diameter of 1 mm whose inner walls were brought into contact with protein solutions of different concentrations (0, 0.1, 1, 10 mg / mL) for a certain period of time were prepared.

[0040] Figure 3 shows the results of measuring the contact angle after treating a flat plate made of the same material as the inner wall of the pipe with the protein solution in the same manner. The contact angles on the flat plate were measured to be 72.3°, 71.9°, 60.2°, and 52.3° respectively.

[0041] The results of evaluating the wettability of the inner walls of the respective pipes with the apparatus of this embodiment will be described.

[0042] Figure 4 shows the relationship between the current value (vertical axis, arbitrary unit) measured in S203 and time (horizontal axis, seconds).

[0043] Figure 5 shows the relationship between the amplitude of the current value measured in Figure 4 (vertical axis, arbitrary unit) and time (horizontal axis, seconds).

[0044] In Figures 4 and 5, in advance, the pipe 1c was filled with an aqueous solution, the introduction of 2 μL of gas was started with the syringe pump 2, and the timing of the start of bubble introduction was set to 0 sec. After approximately 1.0 sec, the gas was moved to the part where the wettability of the pipe 1c was to be evaluated, and the liquid feeding was stopped.

[0045] At this time, as the voltage source 4 to be applied, it is desirable to use alternating current rather than direct current to avoid deterioration of the conductor 3, etc. Also, when using an aqueous solution as the medium, it is desirable that the voltage does not exceed 1.23 V to avoid a decrease in measurement accuracy due to electrolysis of water. Here, an alternating voltage of 10 Hz and 0.2 V was applied.

[0046] Furthermore, it is also possible to change the frequency of the applied voltage, measure the impedance from the relationship between the current value and the applied voltage, and use it as an index for wettability evaluation. It was confirmed that the time change of the current value in each pipe differed depending on the concentration of the protein solution brought into contact in advance.

[0047] The lower the contact angle is measured on the flat plate and the pipe is processed under such conditions, the more gradual the attenuation of the current amplitude tends to be.

[0048] With reference to FIG. 6, the reason why the attenuation of the current amplitude changes depending on the contact angle of the inner wall will be described. FIG. 6 is a schematic diagram of the inner cross-section of pipe 1c.

[0049] In the reference state, the inside of pipe 1c is filled with aqueous solution 50 (F501). 2 μL of gas 51 is introduced using syringe pump 2 (F502) and stopped at the position 52 to be evaluated (F503).

[0050] Immediately after stopping, since there is a liquid film of the aqueous solution between the introduced gas and the wall surface of pipe 1c, the electrical resistance value is in a low state. As this liquid film gradually becomes thinner, the electrical resistance value increases (F504), and eventually the gas comes into contact with the wall surface (F505), and the electrical resistance value rapidly increases.

[0051] In the apparatus of this embodiment, the difference in wettability is detected by utilizing the fact that this change process becomes slower when the wettability of the inner wall of the pipe is high and faster when the wettability is low. The region where the wettability is evaluated by this method is the area where the gas exists centered on position 52. For example, the evaluation range can be changed by controlling the size of the introduced gas, such as narrowing the evaluation region by reducing the introduced gas volume.

[0052] Also, after the evaluation of position 52 is completed, by moving the position of the gas from position 52 to position 53, it is possible to continuously evaluate the inner walls at different positions (F506 to F508).

[0053] As described above, the wettability of the inner wall of the pipe is deeply related to the movement of charges between the first location and the second location sandwiching the position 52. Therefore, by measuring the electrical characteristics of the pipe, it becomes possible to evaluate the wettability of the inner wall of the pipe. In the above, an aqueous solution and a gas were adopted as the first medium and the second medium. However, as long as the first medium and the second medium do not mix with each other and have different electrical resistances, either a gas or a liquid may be used.

[0054] In the evaluation of wettability, the analysis unit 9 acquires the current value fluctuation range from the start of liquid feeding to 2.5 seconds as shown in FIG. 5, and evaluates the wettability from an evaluation table that stores the relationship between current-related values such as the current value fluctuation range and the wettability parameter indicating the degree of wettability, which are stored in the database 10 in advance.

[0055] FIG. 7 shows an example of the evaluation table 700 stored in the database 10. The data in the evaluation table 700 stores in advance the current-related values (applied voltage and current analysis values) obtained from the above-described wettability evaluation using a flow path with a known flow path length, flow path inner diameter, and wettability parameter. By using these relationships, the wettability parameter can be converted from the current-related value.

[0056] Note that the numerical values in the evaluation table 700 differ depending on the material of the wall surface and the types of the medium 1 and the medium 2, and thus are prepared according to the evaluation object.

[0057] As the wettability parameter, for example, the contact angle with the flat plate shown in FIG. 3 can be used. Alternatively, a new parameter based on the current analysis value under predetermined conditions may be adopted. Alternatively, the current analysis value itself may be used as a parameter without conversion.

[0058] As an example of the conversion method, there are a method of calculating using an approximate expression representing the relationship between the current-related value and the wettability parameter in the analysis unit 9, and a method of calculating using a machine learning model or the like when the approximate expression cannot be used. The data in the evaluation table 700 can be rewritten. Thereby, for example, the influence on the measurement error due to the fluctuation of the applied voltage value due to the deterioration of the conductor 3a or the like can be reduced.

[0059] Note that, as a method for converting to the degree of wettability, not limited to the current value amplitude at a certain timing as in the current method, regression parameters calculated using regression analysis such as an exponential function, the integrated value of the current value amplitude in a certain time region, etc. may be used as an index.

[0060] All of these indexes may be stored in the database 10, and the index used for conversion can be changed each time.

[0061] <Example of monitoring the state of the flow path piping> Since the calculated degree of wettability is output to the display unit 11, the maintenance manager can grasp the state of the flow path piping and perform maintenance management before an abnormality occurs. Also, it is possible to predict the replacement timing of the flow path from the change in wettability over time and perform maintenance management before an abnormality occurs. An example of a method for predicting the replacement timing of the flow path will be described with reference to FIGS. 8 and 9.

[0062] FIG. 8 is an example of a threshold database 800 for maintaining the flow path piping of an apparatus for analyzing components in a solution, for example. As shown in FIG. 8, wettability parameters for each solution (medium 1) and thresholds serving as guidelines for the replacement timing are set. Different thresholds can be set depending on the length of the replacement timing. These threshold databases 800 can be stored in the database 10, for example.

[0063] FIG. 9 shows a flowchart for reporting the replacement timing to the user. First, the wettability parameter and the date are acquired by the method described above (S901). Then, each is stored in the database 10 as time-series data (S902).

[0064] The acquired wettability parameter is compared with the threshold (S903), and depending on whether the threshold is exceeded (S904), the process returns to S901 or the user is prompted to replace (S905). Thereby, it is possible to prompt the user to perform maintenance management such as replacing the flow path before an abnormality occurs.

[0065] Fig. 10 graphically shows an example of the time-series data stored in the database 10. The time-series data 1000 shows the relationship between the wettability parameter and the acquisition date (date). In this example, a wettability parameter of 6.5 is set as the threshold value.

[0066] Regardless of whether the threshold is exceeded or not, the user can output the time-series data 1000 to the display unit 11 and check it. The advantage of doing this is that depending on the characteristics of the sample passing through the flow path, the wettability may change rapidly, and it is difficult to accurately predict the replacement time with the threshold setting. Therefore, by observing the change in the wettability parameter over time, it is possible to cope with the wettability evaluation in such irregular usage situations.

[0067] In order to suppress the electrolysis of the sample due to the voltage application by the voltage source 4, it is desirable to apply an alternating voltage with as small a voltage value as possible. Also, by obtaining in advance the relationship between the change in the current value and the contact angle related to the wettability, it is possible to quantitatively evaluate the wettability. Further, in order to evaluate the electrical conductivity in the flow path, it is desirable to use an insulating material such as a material with an electrical resistance value of 1 GΩ or more between the inside and outside of the flow path wall for the flow path piping 1c.

[0068] In this way, in this embodiment, the wettability of any inner wall of the piping 1c can be evaluated. Therefore, by making the piping of the 1c part detachable, it is also possible to replace the piping and evaluate the wettability of the inner wall of another piping.

[0069] In this embodiment, an aqueous solution is used for medium 1 and air is used for medium 2, but any immiscible fluids and substances with different conductivities can be adopted. As long as one has high conductivity and the other has low conductivity, the effects of the embodiment can be exhibited in any combination. For example, a combination of liquids may also be used.

[0070] As described above, according to this configuration, by introducing two different media into the flow path piping and using the current value flowing with respect to the voltage applied to the flow path piping, even for a flow path piping whose interior cannot be observed, it is possible to evaluate the degree of wettability, grasp the state of the flow path piping from the evaluation result, and there is an effect that maintenance management can be carried out before a liquid feeding abnormality occurs.

[0071] [Modification Example of the First Embodiment] FIG. 11 shows a modification example of the measurement unit 100 of the embodiment of FIG. 1. The modification example of FIG. 11 is characterized in that the measurement unit 100-2 has a nozzle 1101 of a conductor having a vertically movable mechanism. When the nozzle 1001 is at the lower part, the aqueous solution in the bottle 7 can be introduced into the pipe 1c, and when the nozzle 701 is moved above the liquid level, air can be introduced. Therefore, the three-way solenoid valve 6a in FIG. 1 is not required.

[0072] Also, by electrically connecting the nozzle 1001 to the voltage source 4 and the ammeter 5, the conductor 3a in FIG. 1 is not required. Although not shown, if a tube pump is used instead of the syringe pump 2, the three-way solenoid valve 6b is also not required, and an even simpler configuration can be achieved.

[0073] As described above, if the measurement unit 100-2 has means for introducing two types of media into the piping of the evaluation target part, means for applying a voltage, and means for measuring the change in the current flowing through the piping, the effects of the embodiment are exhibited.

Example

[0074] An example of applying the wettability evaluation apparatus described in Example 1 to an electrolyte analyzer that measures the electrolyte concentration in a sample solution will be described. The electrolyte analyzer can measure the concentration of a specific electrolyte contained in an electrolyte solution such as blood or urine. The electrolyte analyzer measures the concentration using an ion-selective electrode. As a general measurement method, a sample solution as an electrolyte solution is supplied to the ion-selective electrode, and the potential difference from the reference electrode is measured. Also, a standard solution is supplied to the ion-selective electrode, and the potential difference from the comparative electrode solution is measured in the same manner. As is well known, the electrolyte concentration of the sample solution can be calculated from the potential difference between the two electrodes.

[0075] FIG. 12 shows a wettability evaluation apparatus according to the second embodiment. The measurement unit 1200 of the apparatus of this example includes an ion-selective electrode 1201a and a reference electrode 1201b in addition to the configuration of the measurement unit 100 of Example 1. The suction nozzle 1202 operates to introduce the sample solution from the bottle 7 into the flow path pipe 1c. The reference solution bottle 1203 connected to the flow path pipe 1e stores the reference solution and can supply the reference solution to the flow path pipe 1c. The potential difference between the ion-selective electrode 1201a and the reference electrode 1201b is configured to be measurable by the potentiometer 1204. The reference electrode 1201b can also serve as the conductor 3b.

[0076] This analyzer can measure the electrolyte concentration in the sample solution by measuring the potential difference between the ion-selective electrode 1201a and the reference electrode 1201b. The analysis unit 9 is used for converting the electrolyte concentration by measuring the potential difference. The analysis unit 9 is assumed to have a known electrolyte concentration analysis function.

[0077] In this example, for both the sample solution and the reference solution, the wettability of the flow path pipe 1c can be evaluated by the method described in Example 1.

[0078] As described above, according to this configuration, it is possible to evaluate the degree of wettability of the flow path pipe of the apparatus having the flow path pipe equipped with the ion-selective electrode 1201, grasp the state of the flow path pipe from the evaluation result, perform maintenance management before the occurrence of liquid feeding abnormality, and improve the accuracy of electrolyte analysis.

[0079] [Modification Example of the Second Embodiment] FIG. 13 shows a modification example of the second embodiment. In this modification example, in the wettability evaluation of the flow path piping 1c mounted on the present analyzer, the suction nozzle 1202 is vibrated to change the impedance and a voltage is applied to the flow path piping 1. The current value flowing through the flow path piping 1 is measured using the ammeter 5, and the wettability is evaluated from the analysis of the time change of the current value and the like in the same manner as in Example 1.

[0080] In this configuration, in order to suppress the deterioration and cost of the ion selective electrode 1201, the voltage source 4 described in the first embodiment is not provided, and the voltage application is replaced by the vertical movement of the suction nozzle 1202. In addition to this, the voltage may be applied by the vibration of the bottle 7 or the vibration of the components arranged in the vicinity of the suction nozzle 1202.

[0081] FIG. 14 shows another modification example of the second embodiment. In this modification example, the wettability is evaluated using the time change of the potential value output by the potentiometer 1204 instead of the ammeter 5. At this time, it is necessary to use the specified conditions in advance for the applied voltage value, its frequency, etc., and this information is also stored in the database 10.

[0082] As a result of the phenomena shown in F501 to F505 in FIG. 6 occurring inside the flow path piping 1c, the electrical resistance between the ion selective electrodes 1201a and 1201b increases with time. The time change of the electrical resistance is reflected as the time change of the potential value output by the potentiometer 1204 for the voltage applied by the vertical movement of the suction nozzle 1202. By measuring the time change of this potential value, the wettability can be evaluated.

[0083] As described above, in this modification example, when the device space is limited or as a method for reducing the mounting cost, while substituting the functions of a voltage source, an ammeter, etc. by utilizing the already mounted device configuration, the state of the flow path piping can be grasped by evaluating the wettability, and there is an effect that maintenance management can be carried out before a liquid feeding abnormality occurs.

Explanation of Reference Numerals

[0084] 1 ··· Flow path piping 2 ··· Syringe pump 3 ··· Conductor 4 ··· Voltage source 5 ··· Ammeter 6 ··· Three-way solenoid valve 7 ··· Bottle 8 ··· Air filter 9 ··· Analysis unit 10 ··· Database 11 ··· Display unit 100 ··· Measurement unit 200 ··· Control unit

Claims

1. A flow path into which a first medium and a second medium are introduced, A measuring instrument for measuring the current value flowing through the flow path when the first medium and the second medium are introduced, A control unit for evaluating the wettability of the inner wall surface of the flow path based on the current value, A wettability evaluation device characterized by comprising the above.

2. Characterized by comprising an AC voltage source for applying an AC voltage to the flow path, The wettability evaluation device according to Claim 1.

3. Characterized by comprising a voltage source for applying a voltage not exceeding 1.23 V to the flow path, The wettability evaluation device according to Claim 1.

4. Characterized by comprising a voltage source for applying a voltage generated by mechanical displacement of a component to the flow path, The wettability evaluation device according to Claim 1.

5. Having a configuration for changing the frequency of the applied AC voltage and obtaining impedance, The wettability evaluation device according to Claim 2.

6. Characterized by comprising an ion-selective electrode in the flow path, The wettability evaluation device according to Claim 1.

7. By referring to a table storing the relationship between the current value and the wettability, grasping the wettability of the inner wall surface of the flow path from the current value, and promoting the maintenance of the flow path, The wettability evaluation device according to Claim 1.

8. Characterized by using an aqueous solution and a gas as the first medium and the second medium, The wettability evaluation device according to Claim 1.

9. The flow path is a pipe with an inner diameter of 5 mm or less, The wettability evaluation device according to Claim 1.

10. Characterized by predicting the replacement time of the flow path from the time-series change of the wettability, The wettability evaluation device according to Claim 1.

11. Having means for controlling the introduction position of the medium in the flow path and capable of changing the evaluation target position of the wettability in the flow path, The wettability evaluation device according to Claim 1.

12. The flow path is characterized in that the electrical resistance between the inner wall and the outer wall is 1 GΩ or more, The wettability evaluation device according to Claim 1.

13. A first step of preparing a flow path, A second step of sending a first medium and a second medium to a predetermined position of the flow path, A third step of evaluating the movement of electric charges between a first location and a second location sandwiching the predetermined position of the flow path, A wettability evaluation method including the above.

14. The third step includes a step of evaluating the wettability of the inner wall surface of the flow path at the predetermined position by analyzing the time change of the current value between the first location and the second location. The wettability evaluation method according to claim 13.

15. The third step includes a step of applying alternating voltages with different frequencies to the flow path. The wettability evaluation method according to claim 13.

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