JP4714700B2 - Method for producing polymer electrolyte membrane actuator and polymer electrolyte membrane actuator - Google Patents

Description

  The present invention relates to a method for producing a polymer electrolyte membrane actuator that is driven (curved or deformed) by applying a voltage, and a polymer electrolyte membrane actuator.

  A touch panel display is used as an input device from a user in a small electronic device such as a mobile phone, a digital camera, or a car navigation system display. The touch panel display is a display including an input device that can input a signal to an apparatus by pressing a predetermined portion with a finger or the like. However, in this touch panel type display, the operator can only know the confirmation of the input from the sound that is emitted simultaneously with the input or the color change in the display screen.

In recent years, various devices have been proposed in order for operators including visually handicapped persons to feel a reaction force or to achieve a degree of achievement (feeling of achievement) as when an analog switch is pressed.
As one of such devices, a polymer actuator described in Patent Document 1 below has been proposed. The polymer actuator has a structure in which an ion exchange resin molded product and a metal electrode are provided in an insulated state on the surface of the ion exchange resin molded product, and by applying a potential difference between the metal electrodes in a water-containing state, the ion exchange resin molded product It causes the product to bend and deform.
In this polymer actuator, an ion-exchange resin molded product is adsorbed in an aqueous metal complex solution, and the adsorbed metal complex is reduced to deposit a metal to form a dendritic metal electrode inside the ion-exchange resin molded product. By doing so, an ion exchange resin molded product provided with a metal electrode can be constituted. Since the metal electrode is a dendritic electrode, the electrode area increases, and it is said that practical displacement and stress can be obtained.

Japanese Patent No. 2961125

  However, the dendritic electrode provided on the ion-exchange resin molded article of the polymer actuator adsorbs the metal complex by immersing it in an aqueous solution containing the metal complex, and then deposits the metal into a dendritic shape using a reducing agent. Therefore, it is difficult to control and form the metal electrode layer to a certain thickness by controlling the conditions such as the concentration and temperature of the metal complex. When the thickness of the metal electrode layer is not uniform, the electric field concentrates on the short part of the distance between the dendritic electrodes and shorts, or the dendritic electrodes facing each other due to bending deformation of the ion exchange resin molded product There is a problem that the contact causes a short circuit and further overheats, resulting in the risk of ignition and loss of safety. Such a problem becomes more prominent as the metal electrode layer has a larger area.

  Therefore, in order to solve the above-described problems, the present invention does not require adjustment of the plating treatment for forming the electrode in the polymer electrolyte membrane actuator driven by applying a voltage compared to the prior art, and An object of the present invention is to provide a highly safe polymer electrolyte membrane actuator in which the non-uniformity of the thickness of the metal electrode is improved and the risk of ignition due to short circuit and overheating is low, and a method for manufacturing the actuator.

In order to achieve the above object, the present invention provides a method for producing a polymer electrolyte membrane actuator driven by applying a voltage, wherein the ion exchange capacity of the pair of first polymer electrolyte membranes is low. And joining a membrane material containing a porous membrane as a layer between the pair of first polymer electrolyte membranes to produce a main body, and adsorption for adsorbing metal ions to the main body There is provided a method for producing a polymer electrolyte membrane actuator comprising a step and a reduction step of reducing the metal ions adsorbed on the main body.
Here, the ion exchange capacity refers to, for example, ion exchange capacity (meq / g).

In that case, it is preferable that the said porous membrane is a thing with a low ion exchange capacity with respect to a said 1st polymer electrolyte membrane.
Alternatively, the porous membrane, an ion exchange capacity with respect to the first polymer electrolyte membrane are those equal to or higher, the film material is coated with the porous film and the first polyelectrolyte It is also preferable to include a second polymer electrolyte membrane having a low ion exchange capacity with respect to the membrane .

Furthermore, the present invention is an actuator that is driven by applying a voltage, the actuator layer comprising a pair of first polymer electrolyte membranes impregnated with an electrolyte solution, and the actuator layer, A pair of electrodes provided so as to oppose each other along different surfaces on both sides of the actuator layer, and each of the pair of first polymer electrolyte membranes has the pair of electrodes And the front actuator layer includes an outer layer formed by providing the pair of first polymer electrolyte membranes on the outer surface of the actuator layer so that the pair of electrodes face each other, and It provided so as to be sandwiched between the outer layer and an inner layer made of a film material comprising a porous membrane as a layer with including low layer of ion exchange capacity with respect to the pair of first polymer electrolyte membrane To provide a polymer electrolyte membrane actuator, characterized by.

In that case, it is preferable that the said porous membrane is a thing with low ion exchange ability with respect to a said 1st polymer electrolyte membrane.
Alternatively, the porous membrane, an ion exchange capacity with respect to the first polymer electrolyte membrane are those equal to or higher, the film material is coated with the porous film and the first polyelectrolyte It is also preferable to include a second polymer electrolyte membrane having a low ion exchange capacity with respect to the membrane .

In the method for producing a polymer electrolyte membrane actuator of the present invention, the membrane material is sandwiched between the pair of first polymer electrolyte membranes, and then the adsorption process and the reduction process, that is, the plating process is performed. The membrane material to be an inner layer sandwiched between the first polymer electrolyte membranes includes a layer having a low ion exchange capacity and a porous membrane as a layer with respect to the pair of first polymer electrolyte membranes. For this reason, even if a plating process is performed for a long time, a metal is not substantially deposited on this layer, and an electrode is not formed. Therefore, since the plating process can be performed for a long time, it is less necessary to adjust the plating process than in the prior art.
Further, sufficient metal can be deposited on the pair of first polymer electrolyte membranes of the outer layer, and a metal layer having a thickness equivalent to that of the first polymer electrolyte membrane can be formed uniformly.
Furthermore, in the inner layer of the produced polymer electrolyte actuator, metal is not substantially deposited and the electrodes on both sides are separated by a certain distance, so that the electric field is concentrated and does not cause a short circuit. For this reason, the polymer electrolyte membrane actuator operates smoothly. Further, the dendritic electrodes facing each other are not brought into contact with each other due to the bending deformation of the actuator layer, thereby causing a short circuit. For this reason, the conventional problem that the danger of ignition occurs due to a short circuit and the safety is impaired is solved.
The porous as a porous membrane contained in the membrane material to be sandwiched between the first polymer electrolyte membrane of a pair, low softening temperature, for example, when used as the order of the softening temperature of 100 ° C., for example due to overheating of the order of 100 ° C. Since the membrane itself melts, the current flow is interrupted by itself. Thereby, the conventional problem that the danger of ignition occurs due to overheating due to a short circuit or the like and the safety is impaired is solved.

FIG. 1 (a) is a schematic view showing one embodiment of a polymer electrolyte membrane actuator (hereinafter referred to as actuator) of the present invention.
The actuator 10 shown in FIG. 1A is provided along the surfaces of both sides of the actuator layer 12 so as to face each other in the actuator layer 12 formed of a polymer electrolyte membrane and the actuator layer 12. It mainly includes electrodes 15 and 17 for applying a voltage from both sides of the actuator layer 12, a power source 20 for applying a voltage to the electrodes 15 and 17, and a controller 22 for controlling the application of the voltage.

  The actuator layer 12 is provided on different surfaces on both sides of the actuator layer 12, and the outer layers 14 and 16 are configured so that the same polymer electrolyte membrane is opposed to the polymer electrolyte membrane of the outer layers 14 and 16. And an inner layer 18 provided so as to be sandwiched between the outer layers 14 and 16.

  The outer layers 14 and 16 are not particularly limited as long as they are ion conductive materials, but ion exchange resin membranes can be preferably used particularly from the viewpoint of ion conductivity and durability. The ion exchange resin membrane is not particularly limited. For example, a cation exchange resin membrane, an anion exchange resin membrane, or a both ion exchange resin membrane is used. Among these, a cation exchange resin film is preferable from the viewpoint of operation as an actuator. In the case of a cation exchange resin membrane, a material obtained by introducing a substituent such as a sulfonic acid group or a carboxyl group into polyethylene, polystyrene, polyamide, polyimide, fluorine resin, or the like is used. For example, “Nafion” (registered trademark, product name manufactured by Du Pont) or “Flemion” (registered trademark, product manufactured by Asahi Glass Co., Ltd.) is used as the cation exchange resin membrane. Also, ion exchange resin membranes having a benzimidazole skeleton, or sulfonated polyethersulfone ion exchange resin membranes, polyaryl ether ion exchange resin membranes or sulfonated polyether ether ketone ion exchange resin membranes, and polyimide An ion exchange resin membrane and the like are also exemplified. In addition, as the polymer electrolyte membrane used for the outer layers 14 and 16, a membrane that suppresses migration of anions while securing migration of cation and solvent molecules of the electrolyte solution (having anion capturing ability) is particularly preferably used. .

The inner layer 18 is an ion conductive material and may be a film material including a layer having a lower ion exchange capacity than the ion exchange ability of the outer layers 14 and 16. Examples of the layer configuration of the inner layer 18 include the following modes.
(I) Form composed of polymer electrolyte membrane (II) Form composed of porous membrane (or membrane membrane) (III) Constructed by coating porous membrane (or membrane membrane) with polymer electrolyte membrane Form

(I) Form Consists of Polymer Electrolyte Membrane When the inner layer 18 is formed of a polymer electrolyte membrane, the inner layer 18 differs in composition of the membrane material from the outer layers 14 and 16, and the ion exchange capacity is the outer layer What is necessary is just to use what has a low ion exchange capacity compared with the outer layers 14 and 16, even if it is a film | membrane material with the low composition compared with 14 and 16, or the same composition. For example, “Nafion” (registered trademark) and “Flemion” (registered trademark) having different ion exchange capacities can be used as a pair, or the same “Nafion” (registered trademark) or “Flemion” (registered trademark) can be used. However, those having different ion exchange capacities (meq / g) can also be used. Furthermore, those having different average pore sizes when the polymer electrolyte membrane has a porous structure may be used.
For example, when the above-mentioned “Nafion” (registered trademark) and “Flemion” (registered trademark) are used as a set for the inner layer 18 and the electrodes 15 and 17 are formed by gold plating, a —SO ₃ ^— exchange group is formed. It is preferable to use “Nafion” (registered trademark) having the “Nafion” (registered trademark) for the inner layer 18 and “Flemion” (registered trademark) having a —COO ⁻ exchange group for the outer layers 14 and 16. This is because, when the electrodes 15 and 17 are formed by gold plating, the affinity with gold ions (Au ³⁺ ) is higher in “Flemion” (registered trademark) and the ion exchange ability is higher.

In the present invention, a polymer electrolyte membrane having a lower ion exchange capacity than the polymer electrolyte membranes of the outer layers 14 and 16 is used for the inner layer 18. This is for suppressing the deposition of dendritic metal on the inner layer 18 when an electrode is produced by a plating process to be described later. At this time, for the inner layer 18, those having a high mobility of ions of an electrolyte solution described later, such as lithium ions, and a low mobility of metal ions forming the electrodes 15 and 17 are preferably used.
Alternatively, the average pore size when the polymer electrolyte membrane is considered to be a porous structure is preferably smaller in the inner layer 18 than in the outer layers 14 and 16. This is to suppress the mobility of metal ions and the mobility of the reducing agent when depositing metal in the inner layer 18 as compared with the outer layers 14 and 16 in the production of an electrode by plating treatment described later. is there. As the polymer electrolyte membrane used for the inner layer 18, one that suppresses the movement of anions (having anion capturing ability) while ensuring the movement of cation and solvent molecules of the electrolyte solution is particularly preferably used. The inner layer 18 has a thickness of 1 to 200 μm.

(II) Form comprised of porous membrane (or membrane membrane) When the inner layer 18 is comprised of a porous membrane (or membrane membrane), it may be comprised of a single porous membrane (or membrane membrane), A plurality of porous membranes (or membrane membranes) may be laminated.
When a plurality of layers of porous films (or membrane films) are stacked, the multilayer porous films may be stacked to have different characteristics. For example, by forming a flexible porous membrane on both sides or one side of a porous membrane having high mechanical strength, the mechanical separation of the electrodes 15 and 17 and the conductivity of ions as an actuator can be ensured. Strength can also be secured.

Further, when the actuator 10 abnormally generates heat due to a short circuit of the electrodes 15 and 17 or becomes a high temperature state, the film material can have a function of interrupting conduction between the electrodes 15 and 17. For example, by using a porous film that melts or softens when a predetermined temperature, for example, 100 ° C. is reached, the porous film is blocked at a predetermined temperature, and conduction of the electrodes 15 and 17 can be stopped. The risk of ignition due to an overheated state can be suppressed and safety can be ensured.
Such an inner layer 18 needs to have good adhesion at the joint surface with the outer layers 14 and 16 of the polymer electrolyte membrane from the viewpoint of improving the durability of the actuator 10.

  Note that a material that is electrochemically stable and has a large potential window is suitably used as the porous membrane (or membrane membrane). For example, if it is an organic material, a polyolefin resin film such as polyethylene or polypropylene, a fluorine resin film such as PTFE (polytetrafluoroethylene) or PVDF (polyvinylidene fluoride), etc. may be mentioned, and if it is an inorganic material, glass, Examples thereof include aluminum oxide. Furthermore, the surface of the inner layer 18 may be subjected to a hydrophilic treatment or a hydrophobic treatment. The shape of the pores of the porous membrane is not particularly limited, but it is preferable that the porosity is high from the viewpoint of cation conductivity. The porous film may be a film having a large number of holes, or a film having a structure of a nonwoven fabric or a woven fabric. The film material preferably has flexibility so as not to limit bending and deformation of the actuator layer 12. The porous membrane (or membrane membrane) may be composed of not only one layer but also two or more layers.

(III) Form configured by coating a porous membrane (or membrane membrane) with a polymer electrolyte membrane When configured by coating a porous membrane (or membrane membrane) with a polymer electrolyte membrane, as shown in FIG. In addition, a multilayer structure in which the polymer electrolyte membranes 18b and 18c are coated on both sides of the porous membrane (or membrane membrane) 18a can be mentioned.
When a porous membrane (or membrane membrane) is used that has a lower ion exchange capacity than the polymer electrolyte membranes of the outer layers 14 and 16 or substantially no ion exchange capability, the polymer electrolyte used for coating is used. The membrane is not limited in ion exchange capacity, and for example, a membrane having the same ion exchange capacity as the polymer electrolyte membrane of the outer layers 14 and 16 may be used. On the other hand, when a porous membrane (or membrane membrane) having an ion exchange capacity equal to or higher than that of the polymer electrolyte membrane of the outer layers 14 and 16 is used, the ion exchange capacity is lower than that of the outer layers 14 and 16. A molecular electrolyte membrane may be used for coating the porous membrane. In the present invention, at least an ion exchange capacity lower than that of the polymer electrolyte membranes of the outer layers 14 and 16 may be used for the inner layer 18.
In the multilayered membrane material shown in FIG. 2, when a porous membrane having substantially no ion exchange ability is used for the porous membrane 18a, the polymer electrolyte membranes 18b and 18c are the polymer electrolyte membranes of the outer layers 14 and 16, respectively. Compared to, a material having a lower ion exchange capacity, for example, the same type of membrane material having a low ion exchange capacity can be used. In this case, it has a layer structure of a film material in which the ion exchange capacity gradually decreases from the outer layers 14 and 16 toward the inner layer 18. Alternatively, the inner layer 18 can be formed of a gradient material whose ion exchange capacity gradually decreases from the outer layers 14 and 16 side of the actuator layer 12 toward the center of the inner layer 18.
On the other hand, when a porous membrane having substantially no ion exchange ability is used as the porous membrane 18a, the same type of membrane material as that of the polymer electrolyte membrane of the outer layers 14 and 16 is used, for example, the same ion exchange ability. Those having a capacity can also be used for the polymer electrolyte membranes 18b and 18c.

  When the inner layer 18 has the multilayer structure shown in FIG. 2, the porous membrane 18a and the polymer electrolyte membranes 18b and 18c may be bonded using a slurry solution having a material component of the polymer electrolyte membrane as an adhesive. . Alternatively, the polymer electrolyte membranes 18b and 18c may be formed on the porous membrane 18a by a casting method using a slurry solution having a material component of the polymer electrolyte membrane. In this case, as the polymer electrolyte membranes 18b and 18c, polymer electrolyte membranes of the same material as the outer layers 14 and 16 are preferably used from the viewpoint of adhesion. The inner layer 18 in this form can improve the adhesion in the actuator layer 12 as compared with the form constituted by one layer of the porous film (or membrane film). Furthermore, when the porous membrane 18a is covered with a polymer electrolyte membrane made of the same material as the polymer electrolyte membranes of the outer layers 14 and 16, part of the material of the polymer electrolyte membrane penetrates into the pores of the porous membrane. Therefore, the pores of the porous film 18a are closed, and the metal powder deposited by the plating process is prevented from entering the porous film 18a. Therefore, even if the actuator layer 12 is bent and deformed, it is not short-circuited by the metal powder, and separation between the electrodes 15 and 17 can be ensured. For this reason, the safety of the actuator 10 can be ensured. On the other hand, the polymer electrolyte membrane that closes the pores of the porous membrane 18a transmits cations and anions in the electrolyte solution. Therefore, even if the material of the polymer electrolyte membrane penetrates into the pores of the porous membrane 18a, There is no inconvenience in operation.

  The electrodes (cathodes, anodes) 15 and 17 include a metal provided in a dendritic shape in the outer layers 14 and 16 of the actuator layer 12 from different surfaces on both sides of the actuator layer 12 toward the inside, and the surface of the actuator layer 12. The electrode is formed of a plating film 19 formed on the surface of the actuator layer 12 and is provided with a substantially uniform thickness along both sides of the actuator layer 12. The portions of the electrodes 15 and 17 provided in the actuator layer 12 are regions of the outer layers 14 and 16 in FIG. 1 by a metal that spreads in a dendritic form from both sides of the actuator layer 12 by a so-called electroless plating process described later. Formed inside. The electrodes 15 and 17 are formed by adsorbing metal ions using ion adsorption by the polymer electrolyte membranes of the outer layers 14 and 16, and then reducing the metal ions to deposit the metal. For this reason, the electrodes 15 and 17 have a large electrode area in the outer layers 14 and 16. On the other hand, since a film material having a low ion exchange capacity is used for the inner layer 18, a metal serving as an electrode is not substantially deposited in the inner layer 18 during the plating process for producing the electrode. The electrodes 15 and 17 are made of, for example, gold, platinum, or palladium. In particular, it is preferable to use gold from the viewpoint of flexibility. The electrodes 15 and 17 are produced by a so-called electroless plating process, and are produced by repeating 5 steps described later 3 to 5 times. There is an inner layer 18 provided with no metal between the electrodes 15 and 17, and the electrodes 15 and 17 are separated from each other by a certain distance. A method for manufacturing the electrodes 15 and 17 will be described later.

  The inner layer 18 described above separates the electrodes 15 and 17 of the outer layers 14 and 16 on both sides (upper side and lower side in FIG. 1A), and is along the surfaces on both sides of the actuator layer 12, that is, Provided inside the actuator layer 12 substantially in parallel. In the actuator 10, the cations in the electrolyte solution impregnated in the actuator layer 12 move toward the negative electrode side, and the solvent molecules move along with this movement, whereby the solvent is unevenly distributed on the negative electrode side. The unevenly distributed solvent causes bending and deformation of the actuator layer 12 as shown in FIG. In order to increase the operating speed of the actuator 10 as described above, the inner layer 18 preferably does not suppress the conductivity of the cation when activated by the polymer electrolyte. Further, the thickness of the entire actuator 10 is preferably thin in order to efficiently perform bending and deformation, and therefore the inner layer 18 is also preferably thin.

The power source 20 applies a voltage to give a predetermined potential difference to the electrodes 15 and 17, and a DC power source is used. For example, a voltage of −2 to +2 V is applied between the electrodes 15 and 17 via the controller 22. The
The controller 22 is a part that adjusts the application of voltage in accordance with a control signal from an external device (not shown).

In such an actuator 10, the actuator layer 12 is activated as an actuator by impregnating the electrolyte solution with an electrolyte solution and causing the actuator layer 12 to swell. Any electrolyte solution may be used as long as the electrolyte salt dissolves and has conductivity. For example, lithium ions can be suitably used as the cation. In addition, a cation selected from the group consisting of dialkylimidazolium ions, tetraalkylammonium ions, trialkylimidazolium ions, piperidinium ions, pyrazolium ions, pyrrolium ions, and pyrrolidinium ions can also be used. As anions, AlCl ₄ ⁻ , BF ₄ ⁻ , ClO ₄ ⁻ , PF ₆ ⁻ , SbF ₆ ⁻ , Cl ⁻ , sulfoniumimide anion, (CF ₃ SO ₂ ) ₂ N ⁻ , (C ₂ F ₅ SO ₂ ) Those selected from the group consisting of ₂ N ⁻ can be used. As the solvent, water or a low-volatile non-aqueous solvent, for example, an organic solvent such as propylene carbonate, ethylene carbonate, diethylene glycol, glycerin, sulfolane, and butyrolactone can be used. In particular, a low-volatile organic solvent is preferable from the viewpoint of air operation and long-term use. As the electrolyte solution, an ionic liquid or gel electrolyte which is a salt existing as a liquid even at room temperature can be used.
The actuator 10 is preferably provided with a cover layer (not shown) in order to prevent solvent volatilization.

Next, production of the electrodes 15 and 17 will be described.
The dendritic electrodes 15 and 17 formed on the actuator layer 12 are produced by subjecting the polymer electrolyte membrane of the actuator layer 12 to adsorption treatment and reduction treatment of metal ions. That is, an electroless plating process is performed. Specifically, it is produced by repeating the five steps (a) to (e) once or more, for example, 3 to 5 times.
(A) Cleaning step (b) Swelling step (c) Metal ion adsorption step (d) Metal ion reduction step (e) Cleaning step

As an example of each process, (a) In the cleaning process, the polymer electrolyte membrane of the actuator layer 12 is cleaned by heating in boiling pure water for 1 hour. (B) In the swelling step, the polymer electrolyte membrane is swollen by being immersed in methanol for 1 hour. (C) In the metal ion adsorption step, gold ions are adsorbed on the polymer electrolyte membrane by immersing in a gold phenanthroline complex solution as a plating solution for 12 hours. (D) In the metal ion reduction step, a sodium sulfite aqueous solution is permeated into the polymer electrolyte membrane adsorbed with gold ions to reduce the gold ions and deposit gold. (E) In the washing step, washing is performed by immersing in pure water at 70 ° C. for 30 minutes.

  In the actuator 10 having such a configuration, when a potential difference is applied between the electrodes 15 and 17 in a state where the electrolyte solution is impregnated and swollen and activated, a large number of protons contained in the electrolyte solution are ion-exchanged together with the solvent molecules as a cathode. Large volume change is caused by moving to the side. Thereby, bending deformation occurs as shown in FIG. At this time, since the electrodes 15 and 17 are separated by the inner layer 18 that does not form a dendritic metal, even if bending deformation occurs, the dendritic electrodes do not come into contact as in the prior art, There is no danger of short circuiting due to uneven thickness of the electrodes 15 and 17 and ignition due to overheating.

Next, a method for manufacturing the actuator 10 will be described.
The manufacturing method of the actuator 10 is a method in which the outer layers 14 and 16 and the inner layer 18 of the actuator layer 12 are integrated, and then the electrodes 15 and 17 are provided (plating treatment).

First, as shown in FIG. 3, polymer electrolyte membranes 14 ′, 16 ′ to be the outer layers 14, 16 without electrodes, and a membrane material 18 ′ having a low ion exchange ability to be the inner layer 18 are prepared. . The membrane material 18 ′ is joined so as to be sandwiched between the polymer electrolyte membranes 14 ′ and 16 ′, and the integrated actuator layer 12 is produced. The membrane material 18 ′ may include a layer having a low ion exchange capacity as shown in FIG.
Examples of the bonding method include adhesion and hot pressing. In the case of bonding, the slurry solution having the material components of the polymer electrolyte membranes 14 ′, 16 ′ or the membrane material 18 ′ is applied to the polymer electrolyte membranes 14 ′, 16 ′ and the membrane material 18 ′ and dried. .

  Next, the integrated actuator layer 12 is provided with electrodes 15 and 17 by the electroless plating process described above. The five steps (a) to (e) described above are repeated 3 to 5 times to produce the electrodes 15 and 17. At this time, since the inner layer 18 uses a film material having a lower ion exchange capacity than the outer layers 14 and 16, the inner layer 18 is substantially not formed with a metal serving as an electrode by plating. Therefore, it is not necessary to accurately adjust the plating process conditions as in the prior art.

  In this way, the membrane material of the inner layer 18 is joined and integrated with the outer layers 14 and 16 using a polymer electrolyte membrane having a lower ion exchange capacity than the polymer electrolyte membranes of the outer layers 14 and 16. Then, since an electroless plating process is performed, ion adsorption is suppressed in the portion of the inner layer 18 during the plating process. For this reason, in the reduction process, the metal of the electrodes 15 and 17 is not substantially deposited on the inner layer 18, and no electrode is formed on the inner layer 18. That is, since the electrodes 15 and 17 are formed on the outer layers 14 and 16, the inner layer 18 has a function of separating the electrodes 15 and 17. Therefore, the electric field is concentrated and short-circuited, which has been a problem in the past, the opposing dendritic electrodes come into contact with each other due to bending deformation of the actuator, and further, there is a risk of ignition due to overheating. The problem of being damaged is solved.

〔Example〕
Hereinafter, the actuator 10 was produced using the various methods described above, and it was confirmed whether or not it would function as an actuator.
The manufacturing method of the actuator 10 is shown in Table 1 below.
“Nafion” (registered trademark, trade name, manufactured by Du Pont) in Table 1 is a fluorine-based cation exchange resin membrane, which is a membrane of perfluorosulfonic acid / PTFE copolymer.
In Table 1, PVDF means polyvinylidene fluoride and PE means polyethylene.
Furthermore, “cast Nafion” (registered trademark) in Table 1 means that a 20% ethanol solution of “Nafion” (registered trademark) was used as a slurry to form a film using a casting method. The adhesion of “Nafion” (registered trademark) with an ethanol solution in Table 1 means that an ethanol solution of “Nafion” (registered trademark) was used as an adhesive. “Hot press” in Table 1 is joining under conditions of 150 ° C. and 250 MPa.

  In addition, No. 1-No. In Example 3 (Example), a porous film having substantially no ion exchange ability was used as the film material of the inner layer 18. No. In Example 4 (Example), a polymer electrolyte membrane having a lower ion exchange capacity than the polymer electrolyte membranes of the outer layers 14 and 16 was used as the membrane material of the inner layer 18. No. 5 is a conventional example, which is a conventional actuator, that is, an actuator layer having a single layer structure.

  No. No. 1 is a composition of “Nafion” (registered trademark) / PVDF / “Nafion” (registered trademark). No. 2 is a configuration of “Nafion” (registered trademark) / PE / “Nafion” (registered trademark). Reference numeral 3 denotes a configuration of “Nafion” (registered trademark) / “Nafion” (registered trademark) / PVDF / “Nafion” (registered trademark) / “Nafion” (registered trademark). No. Reference numeral 4 denotes a configuration of “Nafion” (registered trademark) / “Nafion” (registered trademark) / “Nafion” (registered trademark).

No. In the plating process of the actuators 1 to 5, the above-described (a) cleaning process to (e) cleaning process were repeated five times to form electrodes. At this time, in the (a) washing step, the polymer electrolyte membrane of the actuator layer 12 was washed by heating in boiling pure water for 1 hour. (B) In the swelling step, the polymer electrolyte membrane was swollen by immersing in methanol for 1 hour. (C) In the metal ion adsorption step, gold ions were adsorbed on the polymer electrolyte membrane by immersing in a gold phenanthroline complex solution as a plating solution for 12 hours. (D) In the metal ion reduction step, the sodium sulfite aqueous solution was permeated into the polymer electrolyte membrane adsorbed with gold ions to reduce the gold ions to deposit gold. (E) In the cleaning process, the substrate was cleaned by being immersed in pure water at 70 ° C. for 30 minutes.
The actuator layer of the actuator thus manufactured was infiltrated with a lithium perchlorate solution to perform ion exchange to activate the actuator. The actuator was operated by applying a potential of −2 to +2 V to the electrode and sweeping.

No. The actuators of Nos. 1 and 4 (examples) are NO. Compared with the actuator of No. 5 (conventional example), it was confirmed that the actuator operates smoothly without short-circuiting. From this, it was confirmed that a short-circuit does not occur even if the plating process conditions are not strictly controlled, and therefore a safe actuator without the risk of ignition due to a short-circuit can be produced.
No. The inner layer 18 of the actuator (Example 2) is a porous film made of PE, and since the softening temperature is 100 ° C. or lower, the resistance between the electrodes of the actuator when left for 5 minutes in an atmosphere of 100 ° C. Was infinite, and it was confirmed that the electrodes were interrupted. From this, no. It was found that the actuator 2 was disconnected between the electrodes when it was in an abnormally high temperature state. Furthermore, NO. Compared to 5, it was confirmed that the actuator operated smoothly without short-circuiting.
No. No. 3 actuator (example) is NO. Compared to the actuator No. 1, it was confirmed that the repeated operation was greatly improved and the durability was high. This is considered to be because the polymer electrolyte membrane covering the porous membrane of the inner layer 18 uses a polymer electrolyte membrane made of the same material as the outer layers 14 and 16, and thus the adhesion of the joint surface is improved.

  As described above, the method for producing the polymer electrolyte membrane actuator and the polymer electrolyte membrane actuator of the present invention have been described in detail. However, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. Of course, improvements and changes may be made.

(A) is a schematic diagram which shows one Embodiment of the polymer electrolyte membrane actuator of this invention, (b) is a figure explaining operation | movement of the actuator shown to (a). It is a figure explaining the example of a structure of the inner layer provided in the actuator layer of the actuator of this invention. It is a figure explaining one Embodiment of the manufacturing method of the polymer electrolyte membrane actuator of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Polymer electrolyte membrane actuator 12 Actuator layer 14, 16 Outer layer 15, 17 Electrode 18 Inner layer 20 Power supply 22 Controller

Claims (6)

A method for producing a polymer electrolyte membrane actuator that is driven by applying a voltage,
The film material containing a porous membrane as a layer with an ion exchange capacity with respect to the pair of first polymer electrolyte membrane comprises a lower layer, bonded sandwich in the pair of first polymer electrolyte membrane, body A joining step for producing a part;
An adsorption step of adsorbing metal ions on the main body,
A reduction step of reducing the metal ions adsorbed on the main body, and a method for producing a polymer electrolyte membrane actuator. The porous membrane, a method for manufacturing a polymer electrolyte membrane actuator according to claim 1 is low in ion exchange capacity to the first polymer electrolyte membrane. The porous membrane has an ion exchange capacity equivalent to or higher than that of the first polymer electrolyte membrane,
The film material, the porous film coated and wherein the first polymer electrolyte membrane according to claim 1, the ion exchange capacity for the polymer electrolyte membrane contains a lower second polymer electrolyte membrane Actuator fabrication method. An actuator driven by applying a voltage,
An actuator layer formed with a pair of first polymer electrolyte membranes impregnated with an electrolyte solution;
A pair of electrodes provided in the actuator layer so as to face each other along different surfaces on both sides of the actuator layer, and to which a voltage is applied;
Each of the pair of first polymer electrolyte membranes is provided with one of the pair of electrodes,
The actuator layer is sandwiched between an outer layer formed by providing the pair of first polymer electrolyte membranes on the outer surface of the actuator layer so that the pair of electrodes face each other, and the outer layer. An inner layer made of a membrane material including a layer having a low ion exchange capacity with respect to the pair of first polymer electrolyte membranes and including a porous membrane as a layer. Membrane actuator. The porous membrane, the polymer electrolyte membrane actuator according to claim 4 is low in ion exchange capacity to the first polymer electrolyte membrane. The porous membrane has an ion exchange capacity equivalent to or higher than that of the first polymer electrolyte membrane,
The film material, the porous film coated and wherein the first polymer electrolyte membrane according to claim 4, the ion exchange capacity for the polymer electrolyte membrane contains a lower second polymer electrolyte membrane Actuator.

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