Ion introduction device and ion introduction method

Abstract

An iontophoresis device for introducing ions into a living body by means of electrical stimulation via an electrode, the iontophoresis device comprising: a controller; a voltage signal generation unit for adjusting the peak voltage; an output synthesis unit including at least a low-pass filter; an output unit that outputs the pulse signal synthesized by the output synthesis unit to an electrode; an output detection unit that detects the current value output from the output unit and transmits the current value to a controller; when a mode for stepwise increasing the cut-off frequency of the low-pass filter is defined as a first mode and a mode for stepwise decreasing the cut-off frequency of the low-pass filter is defined as a second mode, the controller performs the following current control: a first step of performing the first mode until the current value changes from increasing to decreasing; a second step of switching the first mode to a second mode and implementing the second mode until the current value is changed from increasing to decreasing when the current value is changed from increasing to decreasing in the first step; and a third step of switching the second mode to the first mode when the current value is changed from increasing to decreasing in the second step.

Description

TECHNICAL FIELD

[0001] The present application relates to an iontophoresis device for iontophoresis of a living body. BACKGROUND

[0002] Iontophoresis devices for iontophoresis of a living body by electric stimulation through an electrode are known (for example, refer to Patent Documents 1 and 2). Since the impedance of a living body varies depending on the state of the skin, the environment of use, and the method of use of the device (the area of contact with the skin), it is a long-standing problem to perform electric stimulation in real time based on a target pulse waveform.

[0003] In Patent Document 1, an iontophoresis device for iontophoresis of an ionic drug from the skin is disclosed, characterized by including: an electrode coated with the ionic drug and attached to the surface of the skin; a current detection unit that detects the current value flowing through the electrode; an optimum frequency determination unit that determines the complex permittivity of the skin based on the detected current value, and determines an optimum frequency corresponding to the detected complex permittivity; and a pulse voltage application unit that generates a pulse voltage of the determined optimum frequency and a prescribed duty ratio, and applies the pulse voltage to the electrode.

[0004] In Patent Document 2, a cosmetic liquid agent permeation device for permeating an ionic liquid agent for improving the cosmetic effect into the skin tissue of a human body is disclosed, characterized by including: an electrode coated with the liquid agent and attached to the surface of the skin; a pulse voltage application unit that generates a pulse voltage of an arbitrary frequency between 100 kHz and 1000 kHz and an arbitrary duty ratio between 30 and 50%, and applies the pulse voltage to the electrode.

[0005] PRIOR ART DOCUMENTS

[0006] PATENT DOCUMENTS

[0007] Patent Document 1 Japanese Patent Application Laid-Open No. 2009-11589

[0008] Patent Document 2 Japanese Patent Application Laid-Open No. 2007-319474

[0009] Patent Document 3 Japanese Patent Application Laid-Open No. 2003-102851 SUMMARY

[0010] PROBLEMS TO BE SOLVED BY THE INVENTION

[0011] An object of the present application is to achieve iontophoresis directed to the maximum value of the current flowing through the skin while monitoring the current value.

[0012] MEANS FOR SOLVING THE PROBLEMS

[0013] To solve the above problems, the iontophoresis device of the present application is (1) an iontophoresis device for introducing ions into a living body by electric stimulation via an electrode, comprising: a controller; a voltage signal generation section for adjusting a peak voltage; an output synthesis section including at least a low-pass filter; an output section for outputting a pulse signal synthesized by the output synthesis section to the electrode; an output detection section for detecting a current value output from the output section and sending it to the controller; wherein the controller implements a current control, when a mode in which the cutoff frequency of the low-pass filter is increased stepwise is defined as a first mode and a mode in which the cutoff frequency of the low-pass filter is decreased stepwise is defined as a second mode, the current control including: a first step of implementing the first mode until the current value changes from increasing to decreasing; a second step of switching the first mode to the second mode when the current value changes from increasing to decreasing in the first step, and implementing the second mode until the current value changes from increasing to decreasing; and a third step of switching the second mode to the first mode when the current value changes from increasing to decreasing in the second step.

[0014] (2) The iontophoresis device according to the above (1), wherein the controller, after implementing a preparation process for causing a weak current to flow through the living body, i.e., a first preliminary step, judges the presence or absence of a contact state of the electrode and the living body, in the case where it is judged that the contact state is present, implements a process for causing a base current higher than the weak current to flow through the living body, i.e., a second preliminary step, and after the second preliminary step, starts the current control; and the controller, each time the cutoff frequency is changed in the first mode and the second mode, judges the presence or absence of the contact state of the electrode and the living body, and in the case where it is judged that the contact state is not present, switches from the first mode or the second mode to the first preliminary step.

[0015] (3) The iontophoresis device according to the above (2), wherein the controller, in the second preliminary step, performs a process for increasing a duty ratio or a peak voltage stepwise.

[0016] (4) The iontophoresis device according to any one of the above (1) to (3), wherein the controller maintains a peak voltage constant during implementation of the first mode and the second mode.

[0017] (5) The iontophoresis device according to the above (1) or (2), wherein the first mode and the second mode are implemented by a polarity inversion method in which the polarity of the electrode is alternately changed.

[0018] (6) An iontophoresis method for introducing ions into a living body by electric stimulation via an electrode of an iontophoresis device having a controller, a voltage signal generation section for adjusting a peak voltage, an output synthesis section including at least a low-pass filter, an output section for outputting a pulse signal synthesized by the output synthesis section to the electrode, an output detection section for detecting a current value output from the output section and sending it to the controller, and a current control performed by the controller when a mode in which a cutoff frequency of the low-pass filter is increased stepwise is defined as a first mode and a mode in which the cutoff frequency of the low-pass filter is decreased stepwise is defined as a second mode, wherein the current control includes a first step of performing the first mode until the current value changes from increasing to decreasing, a second step of switching the first mode to the second mode when the current value changes from increasing to decreasing in the first step and performing the second mode until the current value changes from increasing to decreasing, and a third step of switching the second mode to the first mode when the current value changes from increasing to decreasing in the second step.

[0019] Effects of the Invention

[0020] According to the present invention, by controlling the cutoff frequency while monitoring the increase and decrease of the current value, iontophoresis directed to the maximum value of the current flowing through the skin can be achieved. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a perspective view of a cosmetic device.

[0022] Figure 2 is a functional block diagram of a cosmetic device.

[0023] Figure 3 is a flowchart of an iontophoresis method as a whole.

[0024] Figure 4 is a flowchart of a subroutine (current control mode) of Figure 3

[0025] Figure 5 is a schematic view schematically showing a waveform of a weak current.

[0026] Figure 6 is a schematic view schematically showing another waveform of a weak current.

[0027] Figure 7 is a schematic view schematically showing a waveform of a base current. DETAILED DESCRIPTION

[0028] Figure 1 ​is an appearance perspective view of a cosmetic device as an example of an ion introduction device. The cosmetic device 1 includes a frame portion 2, an introduction electrode 3, a counter electrode 4, an on switch 5, an off switch 6, and a battery housing portion 7. The frame portion 2 can be an insulating material such as synthetic resin. However, the present application is not limited to the cosmetic device, but can be any device capable of introducing ions into an arbitrary portion of a living body.

[0029] The introduction electrode 3 corresponds to an output 1 of the output pulse signal to the living body. The counter electrode 4 corresponds to an output 2 of the output pulse signal. Figure 2 Figure 2 If the on switch 5 is operated, the cosmetic device 1 operates, and if the off switch 6 is operated, the cosmetic device 1 stops.

[0030] In the cosmetic device 1, a hygroscopic member (not shown) impregnated with ionized toner is interposed between the introduction electrode 3 and the face as an ion introduction site, and the frame portion 2 is held in a state of covering the counter electrode 4, and ion introduction is started by operating the on switch 5. After the operation is started, the ionized toner in the hygroscopic member can be introduced into the living body by outputting the pulse signal to the introduction electrode 3.

[0031] Figure 2 is a functional block diagram of the cosmetic device 1. The cosmetic device 1 includes a controller 10, a voltage signal generation portion 20, an output synthesis portion 30, an output portion 40, and an output detection portion 50. The controller 10 manages the control of the entire cosmetic device 1, and can use a microcomputer or the like. The microcomputer can include an I / O (input / output), a CPU (central processing unit), a ROM (read only memory), a RAM (random access memory), and the like.

[0032] The controller 10 adjusts the peak voltage by controlling the voltage signal generation portion 20. The peak voltage refers to the highest voltage in one cycle. The voltage signal for the output pulse generated by the voltage signal generation portion 20 is sent to the output synthesis portion 30.

[0033] The output synthesis portion 30 includes a pulse generation portion 31, a filter control portion 32, and an amplification portion 33. The controller 10 controls the frequency and the duty ratio of the pulse signal by controlling the pulse generation portion 31. The controller 10 controls the cutoff frequency of the low-pass filter included in the filter control portion 32. The rise time of the pulse signal is adjusted by controlling the cutoff frequency.

[0034] The controller 10 adjusts the peak voltage by the amplification portion 33 after adjusting the frequency, the duty ratio, and the cutoff frequency of the pulse signal, and generates the output pulse. The generated output pulse is output via the output portion 40. The output detection portion 50 always detects the current output from the output portion 40, and outputs the detection result to the controller 10.

[0035] Next, reference will be made to Figure 3 and​Figure 4 , which details the method of ion introduction using the beauty device 1. Figure 3 This is the overall flow chart of ion introduction. Figure 4 is with Figure 3 The subroutine corresponding to the power control mode (step S104).

[0036] In addition, the iontophoresis method of the present invention does not include medical treatment.

[0037] Reference Figure 3 When the power switch 5 is turned on, the controller 10 performs a "preparation process" for outputting a pulse signal corresponding to a weak current from the output unit 40 (step S101). Step S101 is equivalent to the "first preliminary step." As described later, setting the duty cycle or peak voltage to a low value is equivalent to the "preparation process."

[0038] Based on the detection results from the output detection unit 50, the controller 10 determines whether a weak current is flowing (step S102). If a weak current is detected, the introduction electrode 3 is deemed to be in contact with the skin (step S102: Yes), and the process proceeds to step S103. If no weak current is detected (i.e., the detected current is 0), the process continues to step S101. When the process proceeds to step S103, the controller 10 activates a flag indicating "first skin contact" (hereinafter also referred to as the skin contact flag).

[0039] The weak current is set to a low current value that the user cannot feel the current flowing, and can be obtained in advance by an experiment in which the current flows through a test subject.

[0040] Here, the controller 10 may generate a weak current by reducing the duty ratio by controlling the pulse generator 31. For example, when the reference value of the duty ratio is 50%, a weak current can be generated by setting the duty ratio to a value lower than the reference value. Figure 5 The waveform of a pulse signal with a reduced duty cycle is schematically shown, with the vertical axis representing voltage level and the horizontal axis representing time.

[0041] In this figure, the output is negative, but the present invention is not limited to this. It can also be positive, or it can alternate between negative and positive (polarity reversal mode) (the same applies to the second preliminary step, the first mode, and the second mode described later). A positive output facilitates the penetration of the positive ions of the ionized toner into the skin, while a negative output facilitates the penetration of the negative ions of the ionized toner into the skin. Polarity reversal modes are disclosed, for example, in Patent Document 3.

[0042] Alternatively, the controller 10 may generate a weak current by reducing the peak voltage by controlling the amplifier 33. In this case, the controller 10 maintains the duty ratio at a reference value.Figure 6 A waveform of a pulse signal in which the peak voltage is reduced is schematically shown, with the vertical axis and the horizontal axis being voltage level and time, respectively.

[0043] In step S103, processing of changing the pulse signal output from the output section 40 from the pulse signal corresponding to the weak current to the pulse signal corresponding to the base current is performed. The base current has a current value higher than the weak current. The controller 10 can perform the change from the weak current to the base current by increasing the duty ratio or the peak voltage. The base current can be set to an appropriate current value at which ions can be introduced, and can be found in advance by an experiment performed on a subject.

[0044] Here, it is preferable to perform the above change processing by gradually (in other words, in stages) increasing the duty ratio or the peak voltage. By performing such change processing in stages, less painful electric stimulation can be achieved. That is, if the base current is immediately passed through after the skin is contacted, painful electric stimulation can occur, and thus it is preferable to change from the weak current to the base current in stages.

[0045] After the base current is reached, the current control mode is changed to step S104. As described above, the current flowing to the skin varies depending on the state of the skin (in other words, the living body impedance), the use environment, the use method, and the like. In the current control mode, "current control directed to the maximum value of the current flowing to the skin" is performed, and by such current control, effective ion introduction is achieved. From the viewpoint that no excessive stimulation feeling is given to the skin, the "maximum value of the current flowing to the skin" can be found experimentally by actually performing ion introduction on a plurality of subjects. Furthermore, "directed to the maximum value" means "targeting the maximum value", and does not necessarily mean that the maximum value is reached.

[0046] In the present embodiment, changing the cutoff frequency is taken as the core of the current control. In general, if the cutoff frequency rises, the waveform approaches a rectangular wave, and the current flowing increases. On the other hand, if the cutoff frequency decreases, the waveform changes to have a more rounded shape, and the current flowing decreases.

[0047] Therefore, in order to achieve efficient iontophoresis, the basic idea of the current control is to increase the cutoff frequency stepwise. However, as the iontophoresis proceeds, the current value no longer increases even if the cutoff frequency is increased (i.e., the current value changes from increasing to decreasing). This is because the charge accumulated in the living body increases as the iontophoresis proceeds. In this case, the mode is switched to one in which the cutoff frequency is decreased stepwise. By decreasing the cutoff frequency, the current easily flows because the charge released from the living body is more than the charge applied to the living body, and thus the current value increases despite the decrease in the cutoff frequency. As the discharge of the living body proceeds, the current value decreases at a certain time, and thus the iontophoresis is continued by increasing the cutoff frequency again. In this way, by controlling the cutoff frequency while monitoring the increase and decrease of the current value, iontophoresis directed to the maximum value of the current flowing through the skin can be achieved. The current control mode of the present application is based on the above insight.

[0048] The content of the current control mode will be described in detail below with reference to the subroutines shown in Figs. 8 to 10. Figure 4 The controller 10 determines whether the skin contact of the introduction electrode 3 is the first time based on the above-described skin contact flag (step S201).

[0049] When the user is in the first skin contact (step S201: Yes), the process proceeds to step S202. In step S202, the controller 10 controls the filter control section 32 to start iontophoresis in which the cutoff frequency is increased by one stage with respect to the base current, and the process proceeds to step S203. By increasing the cutoff frequency, the high-frequency band more easily passes.

[0050] In step S203, the controller 10 starts the first mode as the state monitoring flag, and the process proceeds to step S105. In addition, the controller 10 updates the skin contact flag to "second skin contact" when the first mode is set in step S203.

[0051] In step S105, the controller 10 determines whether the introduction electrode 3 is continuously in contact with the skin. Since the determination method is the same as that in step S102, the description will not be repeated. In the case where the skin contact is continued (step S105: Yes), the process proceeds to step S106. In the case where the skin contact is interrupted, the process returns to step S101. When returning to step S101, the controller 10 stops the state monitoring flag and the skin contact flag.

[0052] In step S106, the controller 10 determines whether a predetermined iontophoresis time has elapsed. Here, the iontophoresis time can be set to an appropriate time for achieving desired iontophoresis based on the current control mode. Therefore, in the case where the process proceeds from step S203 via step S105 to step S106, the process returns to step S201 because the iontophoresis time has not elapsed.

[0053] Since the skin contact flag is updated to "second skin contact", the process returns to step S201 and proceeds to step S204. In step S204, the controller 10 determines whether a predetermined time has elapsed since the cutoff frequency was increased in step S202 (in other words, after the waveform was shaped). The predetermined time is preferably a time of one cycle of the pulse frequency or more.

[0054] In the case where the predetermined time has elapsed after the waveform was shaped (step S204: YES), the process proceeds to step S205. In the case where the predetermined time has not elapsed after the waveform was shaped (step S204: NO), the process proceeds to step S105. After proceeding to step S105, the processes of step S105, step S106, step S201, and step S204 are repeated until the predetermined time elapses.

[0055] In step S205, the controller 10 determines whether the state monitoring flag is in the first mode. As described above, since the first mode is started in step S203, the process proceeds to step S206 (step S205: YES). In step S206, the controller 10 determines whether the current value has increased based on the detection result of the output detection section 50. In the case where the current value has increased, the process proceeds to step S210. In the case where the current value has not increased, the process proceeds to step S208. In the case where the current value reaches the maximum current, the process also proceeds to step S208. Here, in the first step S205, since the charge accumulated in the living body is small immediately after shifting to the current control mode, it is generally determined that the current value has increased.

[0056] In step S210, the controller 10 further increases the cutoff frequency by one level, and then the process proceeds to step S105. By increasing the cutoff frequency, the current value increases, and thus the iontophoresis can be promoted. Here, when the value of the cutoff frequency before the increase is set to 100%, it is preferable to set the increase amplitude of one level to about 15 to 25%. The same applies to the decrease amplitude when the cutoff frequency is decreased in stages.

[0057] Here, the processes of step S105 → step S106 → step S201 → step S204 → step S205 → step S206 → step S210 (corresponding to the first step) are repeated for a short time. Thereby, the iontophoresis can be actively performed while the current value is increased.

[0058] As time passes, when the charge accumulated in the living body becomes large, the current value detected by the output detection section 50 changes from increasing to decreasing, and thus the process shifts from step S206 to step S208 (step S206: No). In step S208, the controller 10 activates the second mode as the state monitoring flag. That is, the state monitoring flag is updated from the first mode to the second mode, and the process proceeds to step S211.

[0059] In step S211, the controller 10 lowers the cutoff frequency by one level, and the process proceeds to step S105. By lowering the cutoff frequency, the charge of the discharge becomes more than the charge applied to the living body, and thus it is possible to gradually reduce the charge accumulated in the living body while continuing ion introduction. As described above, when the cutoff frequency is lowered, although the current value decreases in design, the current easily flows because the charge accumulated in the living body decreases, and thus the current value increases.

[0060] That is, after proceeding to step S105, the process of step S106→step S201→step S204→step S205→step S207→step S208→step S211 is repeated until it is determined in step S207 that the current value decreases (corresponding to the second step). When the charge accumulated in the living body sufficiently decreases, the current value changes from increasing to decreasing (step S207: No), and the process proceeds to step S209.

[0061] In step S209, the controller 10 activates the first mode as the state monitoring flag. That is, the state monitoring flag is updated from the second mode to the first mode, and the process proceeds to step S210 (corresponding to the third step). Here, in the case of shifting from step S209 to step S210, since the charge accumulated in the living body sufficiently decreases, it is possible to increase the current value by increasing the cutoff frequency. Thus, it is possible to promote ion introduction. Here, in the first mode and the second mode, the controller 10 maintains the peak voltage constant. That is, in the first mode and the second mode, since the current control is performed by changing the cutoff frequency while maintaining the peak voltage constant, it is possible to avoid adverse effects on the living body.

[0062] Symbol Explanation

[0063] 1 Cosmetic device

[0064] 2 Frame section

[0065] 3 Introduction electrode

[0066] 4 Counter electrode

[0067] 5 Power-on switch

[0068] 6 Power-off switch

[0069] 7 Battery housing section

[0070] 10 controller

[0071] 20 voltage signal generating section

[0072] 30 output synthesizing section

[0073] 31 pulse generating section

[0074] 32 filter control section

[0075] 33 amplifying section

[0076] 40 output section

[0077] 50 output detecting section

Claims

1. An iontophoresis device for introducing ions into a living body by electric stimulation through electrodes, characterized by comprising: having: a controller; a voltage signal generation section for adjusting a peak voltage; an output synthesis section including at least a low-pass filter; an output section for outputting a pulse signal synthesized by the output synthesis section to the electrode; an output detection section for detecting a current value output from the output section and sending it to the controller; when a mode for gradually increasing a cutoff frequency of the low-pass filter is defined as a first mode and a mode for gradually decreasing the cutoff frequency of the low-pass filter is defined as a second mode, the controller implements a current control including: a first step of implementing the first mode until a current value changes from increasing to decreasing; a second step of switching the first mode to the second mode when the current value changes from increasing to decreasing in the first step, and implementing the second mode until the current value changes from increasing to decreasing; a third step of switching the second mode to the first mode when the current value changes from increasing to decreasing in the second step.

2. The iontophoresis device according to claim 1, wherein the controller, after implementing a preparation process for causing a weak current to flow through a living body, i.e., a first preliminary step, judges the presence or absence of a contact state of the electrode and the living body, in the case of judging contact, implements a process for causing a basic current higher than the weak current to flow through the living body, i.e., a second preliminary step, and after the second preliminary step, starts the current control; the controller, each time the cutoff frequency is changed in the first mode and the second mode, judges the presence or absence of the contact state of the electrode and the living body, and in the case of judging non-contact, switches from the first mode or the second mode to the first preliminary step.

3. The iontophoresis device according to claim 2, wherein the controller, in the second preliminary step, performs a process for gradually increasing a duty ratio or a peak voltage.

4. The iontophoresis device according to any one of claims 1 to 3, wherein the controller, during implementation of the first mode and the second mode, maintains the peak voltage constant.

5. The iontophoresis device according to claim 1 or 2, wherein the first mode and the second mode are implemented by a polarity inversion method in which the polarity of the electrode is alternately changed.

6. An iontophoresis method for introducing ions into a living body by electric stimulation via an electrode of an iontophoresis device for non-therapeutic and non-diagnostic purposes, characterized in that the iontophoresis device has: a controller; a voltage signal generation section for adjusting a peak voltage; an output synthesis section including at least a low-pass filter; an output section for outputting a pulse signal synthesized by the output synthesis section to the electrode; an output detection section for detecting a current value output from the output section and sending it to the controller; when a mode for gradually increasing a cutoff frequency of the low-pass filter is defined as a first mode and a mode for gradually decreasing the cutoff frequency of the low-pass filter is defined as a second mode, the controller implements a current control including: a first step of implementing the first mode until a current value changes from increasing to decreasing; a second step of switching the first mode to the second mode when the current value changes from increasing to decreasing in the first step, and implementing the second mode until the current value changes from increasing to decreasing; a third step of switching the second mode to the first mode. In a third step, the second mode is switched to the first mode when the current value changes from increasing to decreasing in the second step.

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