Apparatus for producing electrolyte membrane with catalyst layer

Abstract

To provide a manufacturing device capable of improving appearance quality of an electrolyte membrane with a catalyst layer.SOLUTION: A manufacturing apparatus for manufacturing a catalyst layer-attached electrolyte membrane by applying a catalyst ink to a surface of a polymer electrolyte membrane includes a transport unit that transports the polymer electrolyte membrane in a transport direction along a longitudinal direction orthogonal to a width direction, a catalyst ink discharge unit that discharges the catalyst ink to the surface of the polymer electrolyte membrane, and a chemical liquid discharge unit that discharges a mixed chemical liquid to the surface of the polymer electrolyte membrane at a position on an upstream side of the catalyst ink discharge unit in the transport direction, in which the mixed chemical liquid includes a first chemical liquid containing at least water and a second chemical liquid containing a liquid having an evaporation rate slower than that of water.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an apparatus for manufacturing a catalyst-coated electrolyte membrane. [Background technology]

[0002] BACKGROUND ART Conventionally, there has been known a manufacturing apparatus for manufacturing an electrolyte membrane with a catalyst layer by applying a catalyst ink to the surface of a polymer electrolyte membrane (for example, Patent Document 1).

[0003] The manufacturing apparatus of Patent Document 1 includes a liquid application process in which a liquid is applied to the bonding surface of the catalyst layer with the electrolyte membrane before bonding, and a thermocompression bonding process in which the catalyst layer with the liquid applied and the electrolyte membrane are bonded by thermocompression bonding. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 7234928 Summary of the Invention [Problem to be solved by the invention]

[0005] The manufacturing apparatus of Patent Document 1 has room for improvement in terms of improving the appearance quality of the catalyst layer-equipped electrolyte membrane.

[0006] Therefore, an object of the present disclosure is to solve the above-mentioned problems and to provide a manufacturing apparatus for a catalyst coated electrolyte membrane that can improve the appearance quality of the catalyst coated electrolyte membrane. [Means for solving the problem]

[0007] The manufacturing apparatus for a catalyst-coated electrolyte membrane according to the present disclosure is a manufacturing apparatus for manufacturing a catalyst-coated electrolyte membrane by applying a catalyst ink to the surface of a polymer electrolyte membrane, and includes: a conveying unit that conveys the polymer electrolyte membrane in a conveying direction along a longitudinal direction perpendicular to the width direction; a catalyst ink ejection unit that ejects catalyst ink onto the surface of the polymer electrolyte membrane; and a chemical solution ejection unit that ejects a mixed chemical solution onto the surface of the polymer electrolyte membrane at a position upstream of the catalyst ink ejection unit in the conveying direction, wherein the mixed chemical solution includes a first chemical solution containing at least water and a second chemical solution containing a liquid whose evaporation rate is slower than that of water. [Effects of the Invention]

[0008] According to the present disclosure, it is possible to improve the appearance quality of a catalyst-coated electrolyte membrane. [Brief explanation of the drawings]

[0009] [Figure 1] Schematic diagram of a manufacturing apparatus according to an embodiment [Figure 2] 1 is a schematic diagram showing the peripheral configuration of a chemical liquid ejection unit according to an embodiment; [Figure 3] Table showing specifications of substances that can be used for chemical solutions 1 and 2 [Figure 4] Table showing conditions and results of Examples and Comparative Examples [Figure 5] Graph showing an example of a detection result by a detection unit according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Ion-conductive polymer electrolyte membranes are used as solid electrolytes in electrochemical devices such as fuel cells, electrolysis cells, sensors, etc. In recent years, there has been a remarkable trend toward thinner polymer electrolyte membranes and increased ion exchange capacity (IEC value) in order to improve the power generation performance and ionic conductivity of electrochemical devices.

[0011] Conventionally, electrode catalysts for fuel cells, electrolysis cells, sensors, etc., that use solid electrolyte membranes can be formed by applying a catalyst ink to at least one surface of a polymer electrolyte membrane and drying the ink. Coating methods include spraying and die coating, but the direct application method using die coating is industrially preferred because it has the advantages of easily achieving adhesion between the electrolyte membrane and the catalyst layer and is economical.

[0012] Polymer electrolyte membranes, which are the substrates to be coated, are highly water-absorbent, and it is known that the moisture content in the membrane varies greatly depending on the environmental atmosphere, such as humidity. For example, if catalyst ink is directly applied in a dry, low-humidity atmosphere, the resulting catalyst-layered polymer electrolyte membrane will swell and shrink, deforming, and impairing its appearance quality. Furthermore, the solvent from the catalyst ink that has permeated the polymer electrolyte membrane may remain, adversely affecting the durability and electrochemical properties of the coating.

[0013] For example, Japanese Patent No. 5813257 discloses an electrode catalyst ink composition that optimizes the SP value and evaporation rate of the additive solvent as a method for forming a polymer electrolyte membrane with a catalyst layer without impairing the appearance quality.

[0014] However, it is difficult to completely suppress fluctuations in the water content of highly hygroscopic polymer electrolyte membranes by optimizing the catalyst ink alone. Furthermore, while rare precious metal catalysts (PGMs) such as platinum have traditionally been used as electrode catalysts, in recent years, inexpensive non-precious metal catalysts such as Ni, Fe, and Co have been investigated. It is known that the use of these non-precious metal catalysts increases the amount of catalyst ink applied, making it essential to take measures other than optimizing the catalyst ink.

[0015] During the application of catalyst ink, it is necessary to maintain the humidity within a certain range to prevent fluctuations in the water content of the polymer electrolyte membrane. For example, one possible method is to store the polymer electrolyte membrane offline in a constant humidity environment in advance, but in the coating line (inline), although the temperature during coating is controlled to a constant value, the humidity is not controlled.

[0016] In view of the above circumstances, the inventors of the present disclosure have found that by applying a mixed chemical solution containing at least a first chemical solution containing water and a second chemical solution containing a liquid having an evaporation rate slower than that of water to a polymer electrolyte membrane, it is possible to control with high precision the variation in water content in a highly hygroscopic polymer electrolyte membrane, thereby improving the appearance quality of the polymer electrolyte membrane.

[0017] (Embodiment)

[0018] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0019] With reference to FIG. 1, a manufacturing apparatus for a catalyst-coated electrolyte membrane according to an embodiment of the present disclosure will be described.

[0020] 1 is a schematic diagram of a manufacturing apparatus 2 for a catalyst-coated electrolyte membrane according to an embodiment of the present invention.

[0021] The manufacturing apparatus 2 shown in FIG. 1 is a manufacturing apparatus for applying a catalyst ink to the surface of a polymer electrolyte membrane M to manufacture an electrolyte membrane with a catalyst layer.

[0022] The manufacturing apparatus 2 includes a transport unit 3, a catalyst ink ejection unit 4, a chemical solution ejection unit 6, a first detection unit 8, a second detection unit 9, and a control unit 10.

[0023] The transport unit 3 is a member for transporting the polymer electrolyte membrane M in the transport direction A1. The transport unit 3 transports the polymer electrolyte membrane M in the transport direction A1 along a longitudinal direction perpendicular to the width direction of the polymer electrolyte membrane M. The transport unit 3 of this embodiment is a conveyor that transports the polymer electrolyte membrane M by engaging a plurality of pulleys with the back surface of the polymer electrolyte membrane M. The transport unit 3 is not limited to this configuration, and any configuration may be adopted as long as it is capable of transporting the polymer electrolyte membrane M in the transport direction A1.

[0024] The catalyst ink ejection unit 4 is a member that ejects catalyst ink onto the surface of the polymer electrolyte membrane M. The catalyst ink ejection unit 4 is disposed so as to eject catalyst ink at a predetermined ejection position P1 onto the surface of the polymer electrolyte membrane M being transported in the transport direction A1. The catalyst ink ejection unit 4 may eject the catalyst ink by any method, such as a die coating method or a spray method.

[0025] The chemical solution discharger 6 is a member that discharges the mixed chemical solution onto the surface of the polymer electrolyte membrane M. The chemical solution discharger 6 is disposed so as to discharge the mixed chemical solution at a predetermined discharge position P2 onto the surface of the polymer electrolyte membrane M being transported in the transport direction A1. The discharge position P2 is located upstream of the discharge position P1 in the transport direction A1. In other words, the chemical solution discharger 6 discharges the mixed chemical solution onto the surface of the polymer electrolyte membrane M before the catalyst ink is discharged.

[0026] The mixed chemical solution contains at least water and has the function of increasing and adjusting the water content of the highly hygroscopic polymer electrolyte membrane M. By ejecting the mixed chemical solution before ejecting the catalyst ink to increase the water content of the polymer electrolyte membrane M in advance, it is possible to prevent the polymer electrolyte membrane M from swelling, shrinking, and deforming due to a sudden change in water content when the catalyst ink is applied. This leads to an improvement in the appearance quality of the polymer electrolyte membrane M. The detailed components of the mixed chemical solution will be described later.

[0027] The first detection unit 8 and the second detection unit 9 are each a member for detecting the amount of a substance component on the surface of the polymer electrolyte membrane M. The first detection unit 8 is disposed downstream in the transport direction A1 from the discharge position P2, and detects the amount of a substance component on the surface of the polymer electrolyte membrane M after the mixed chemical solution is discharged. The second detection unit 9 is disposed upstream in the transport direction A1 from the discharge position P2, and detects the amount of a substance component on the surface of the polymer electrolyte membrane M before the mixed chemical solution is discharged.

[0028] By referring to the detection results of the two detection units 8 and 9, it is possible to identify changes in the surface condition of the polymer electrolyte membrane M due to the discharge of the mixed chemical solution by the chemical solution discharge unit 6, and to confirm the extent to which water and other substances contained in the mixed chemical solution have adhered to and penetrated into the polymer electrolyte membrane M.

[0029] The detection units 8 and 9 of this embodiment are each infrared absorption spectrometers that measure the absorption spectrum by irradiating the surface of the polymer electrolyte membrane M with infrared light. By measuring the infrared absorption spectrum, the amounts of water and other substances on the surface of the polymer electrolyte membrane M can be detected with high accuracy.

[0030] The control unit 10 is a component that controls the discharge of the mixed chemical liquid by the chemical liquid discharge unit 6. The control unit 10 of this embodiment is electrically connected to the chemical liquid discharge unit 6 and the detection units 8 and 9, and controls the discharge of the mixed chemical liquid by the chemical liquid discharge unit 6 based on the detection results of the detection units 8 and 9. A specific control method will be described later.

[0031] The control unit 10 can be configured with, for example, a CPU, an MPU, a DSP, an FPGA, an ASIC, etc. The functions of the control unit 10 may be configured with hardware alone, or may be realized by combining hardware and software. The control unit 10 realizes predetermined functions by reading data and programs stored in a storage area (not shown) within the control unit 10 and performing various arithmetic processing.

[0032] The control unit 10 may be electrically connected to the transport unit 3 and the catalyst ink discharge unit 4 in addition to the chemical solution discharge unit 6 and the detection units 8 and 9. The control unit 10 may be electrically connected to another control unit that controls the transport unit 3 and the catalyst ink discharge unit 4, for example.

[0033] FIG. 2 is a schematic diagram showing the peripheral configuration of the chemical solution discharge unit 6. As shown in FIG.

[0034] As shown in FIG. 2, chemical liquid discharge unit 6 includes first chemical liquid source 12, second chemical liquid source 14, first chemical liquid supply unit 16, second chemical liquid supply unit 18, and discharge unit 20.

[0035] The first chemical liquid source 12 contains a first chemical liquid, which is a raw material for the mixed chemical liquid. The first chemical liquid is a liquid containing at least water. The second chemical liquid source 14 contains a second chemical liquid, which is a raw material for the mixed chemical liquid. The second chemical liquid contains a liquid whose evaporation rate is slower than that of water.

[0036] The chemical liquid sources 12 and 14 are, for example, tanks that store chemical liquid, but any configuration may be adopted as long as it is capable of supplying chemical liquid.

[0037] First chemical liquid supply unit 16 is a member for supplying the first chemical liquid stored in first chemical liquid source 12 to discharge unit 20. Second chemical liquid supply unit 18 is a member for supplying the second chemical liquid stored in second chemical liquid source 14 to discharge unit 20. By supplying two types of chemical liquid to discharge unit 20 by chemical liquid supply units 16 and 18, discharge unit 20 discharges a mixed chemical liquid that is a mixture of the first chemical liquid and the second chemical liquid (arrow B).

[0038] The chemical liquid supply units 16 and 18 are configured to be able to change the amount of chemical liquid supplied, respectively. The control unit 10 controls the amount of chemical liquid supplied by the chemical liquid supply units 16 and 18, thereby adjusting the mixing amount / mixing ratio of the first chemical liquid and the second chemical liquid in the mixed chemical liquid.

[0039] The chemical liquid supply units 16 and 18 of this embodiment may have any configuration as long as the amount of chemical liquid supplied can be changed.

[0040] Next, examples of the components of the first and second chemical solutions will be described.

[0041] FIG. 3 is a table showing specifications regarding materials that can be used for the chemical solutions 1 and 2.

[0042] In Figure 3, "Classification" indicates the classification to which each substance belongs. "Name" indicates the name and chemical formula of each substance. "Evaporation Rate" indicates the evaporation rate of each substance (unit: no unit) and is expressed as a relative evaporation rate when the evaporation rate of butyl acetate is set at 100. "Dissolution Rate" indicates the dissolution rate of each substance (unit: mg / L) and is expressed as the dissolution rate specified in the ASTM D 3539-87 standard test method.

[0043] "Miscibility with water" indicates miscibility with water based on the dissolution rate. The faster the dissolution rate, the higher the miscibility with water, and the slower the dissolution rate, the lower the miscibility with water. In the table in Figure 3, a dissolution rate of 1.00*10^6 (maximum) is rated as "◎" (very high miscibility), a dissolution rate slower than 1.00*10^6 and greater than 100 is rated as "〇" (high miscibility), and a dissolution rate slower than 100 is rated as "×" (low miscibility).

[0044] "Chemical Solution 1 / Chemical Solution 2" indicates whether or not a substance can be suitably used as Chemical Solution 1 or Chemical Solution 2. Those that can be suitably used as Chemical Solution 1 are designated "Chemical Solution 1," those that can be suitably used as Chemical Solution 2 are designated "Chemical Solution 2," and those that cannot be suitably used as Chemical Solutions 1 or 2 are designated "-."

[0045] It is preferable that the chemical liquid 1 containing at least water contains a liquid that evaporates faster than water and is highly miscible with water. As shown in Figure 3, the following alcohols can be suitably used as the chemical liquid 1: "methanol," "ethanol," "isopropyl alcohol," "n-propyl alcohol," "isobutyl alcohol," and "n-butyl alcohol," glycol ethers: "propylene glycol methyl ether," ketones: "acetone" and "methyl ethyl ketone," and esters: "ethyl acetate" and "propyl acetate."

[0046] The chemical solution 2 having a slower evaporation rate than water preferably contains a liquid having a slower evaporation rate than water and high miscibility with water. As shown in Figure 3, glycol ethers such as "dipropylene glycol methyl ether," "propylene glycol n-propyl ether," "dipropylene glycol n-propyl ether," "diethylene glycol methyl ether," "ethylene glycol n-propyl ether," "ethylene glycol n-butyl ether," "ethylene glycol t-butyl ether," "3-methoxy-3-methyl-1-butanol," "ethylene glycol n-butyl ether acetate," "propylene glycol methyl ether acetate," "dipropylene glycol methyl ether acetate," "propylene glycol diacetate," "dicyclohexanone," "diacetone alcohol," and "isophorone" can be suitably used as the chemical solution 2.

[0047] By using chemical liquid 1 containing at least water, it is possible to improve and adjust the water content on the surface of the polymer electrolyte membrane M. Furthermore, by mixing a liquid that evaporates faster than water and is highly miscible with water into chemical liquid 1, the water and liquid in a mixed state can easily penetrate into the polymer electrolyte membrane M, making it easier to achieve the effect of improving and adjusting the water content. By mixing chemical liquid 2, which evaporates slower than water, in addition to chemical liquid 1, it is possible to suppress the evaporation of chemical liquid 1, making it easier to ensure that liquid 1 has enough time to penetrate into the polymer electrolyte membrane M.

[0048] Next, examples and comparative examples based on the table of FIG. 3 will be described with reference to FIG.

[0049] FIG. 4 shows the conditions and results for Examples 1 to 3 and Comparative Examples 1 to 4.

[0050] As shown in Fig. 4, at least one of water, ethanol, and toluene was used as chemical solution 1. According to the table in Fig. 3, water and ethanol are suitable for chemical solution 1, but toluene is not suitable for chemical solution 1. Furthermore, one of 3-methoxy-3-methyl-1-butanol (Solfit (registered trademark)), 3-methoxybutyl acetate, and DMF was used as chemical solution 2. According to the table in Fig. 3, 3-methoxy-3-methyl-1-butanol is suitable for chemical solution 2, but 3-methoxybutyl acetate and DMF are not suitable for chemical solution 2.

[0051] The "evaporation rate" and "dissolution rate" indicate the same values ​​as the "evaporation rate" and "dissolution rate" in the table of FIG.

[0052] The column to the right of "Dissolution rate" shows the mixing ratio of the substances in the mixed chemical solution used in each Example and Comparative Example.

[0053] In Examples 1 to 3, a mixed liquid of water and ethanol is used as Chemical Solution 1, and 3-methoxy-3-methyl-1-butanol is used as Chemical Solution 2. In Examples 1 to 3, the mixing ratio of each liquid is different; for example, in Example 1, the ratio is 0.5% water, 69.5% ethanol, and 30.0% 3-methoxy-3-methyl-1-butanol.

[0054] In Comparative Example 1, ethanol is used as Chemical Solution 1, and 3-methoxy-3-methyl-1-butanol is used as Chemical Solution 2. The "water content in the mixed chemical solution" in Comparative Example 1 is 0%.

[0055] In Comparative Examples 2 to 4, toluene, which has a slow dissolution rate, was used instead of ethanol as Chemical Solution 1. In Comparative Example 3, 3-methoxybutyl acetate, which has a slow dissolution rate, was used instead of 3-methoxy-3-methyl-1-butanol as Chemical Solution 2. In Comparative Example 4, DMF, which has a very slow evaporation rate, was used instead of 3-methoxy-3-methyl-1-butanol as Chemical Solution 2.

[0056] In the "Results" section of Figure 4, "Water content adjustment effect" indicates the magnitude of the effect of adjusting the water content on the surface of the polymer electrolyte membrane M with the water contained in the chemical solution 1. A large effect of improving and adjusting the water content is indicated by "◯", and a small effect is indicated by "X".

[0057] In Examples 1 to 3, ethanol, which has a fast evaporation rate and a fast dissolution rate, was mixed with water in Chemical Solution 1, and 3-methoxy-3-methyl-1-butanol, which has a slow evaporation rate and a fast dissolution rate, was used in Chemical Solution 2. Therefore, the water content of the polymer electrolyte membrane M could be significantly adjusted based on the principle described in relation to the table in Fig. 3 .

[0058] In Comparative Example 1, the drug solution 1 did not contain water, and therefore the effect of adjusting the water content of the polymer electrolyte M could not be achieved.

[0059] In Comparative Examples 2 to 4, the dissolution rate of toluene contained in chemical solution 1 was slow, resulting in poor miscibility between water and toluene, and thus poor penetration of water into the polymer electrolyte membrane M. Furthermore, in Comparative Example 3, the dissolution rate of 3-methoxybutyl acetate contained in chemical solution 2 was slow, resulting in poor miscibility between chemical solution 1 and chemical solution 2, and therefore the effect of suppressing evaporation of chemical solution 1 was difficult to achieve. Furthermore, in Comparative Example 4, the evaporation rate of DMF contained in chemical solution 2 was extremely slow, making it difficult for chemical solution 1 to evaporate excessively, and substances such as toluene contained in chemical solution 1 were likely to remain, leading to a deterioration in the surface condition of the polymer electrolyte membrane M. For these reasons, Comparative Examples 2 to 4 were rated "poor" for the "water content adjusting effect."

[0060] In the "Results" section of Figure 4, "Appearance Quality" shows the results of visually inspecting the appearance quality of the polymer electrolyte membrane M when a mixed chemical solution containing chemical solutions 1 and 2 was ejected onto the polymer electrolyte membrane M using the manufacturing apparatus 2 shown in Figure 1 to adjust the water content, and then a catalyst ink was ejected.

[0061] When no appearance abnormalities such as swelling or whitening are observed in the polymer electrolyte membrane M, the membrane is rated as "◎" (very good appearance quality), when almost no appearance abnormalities are observed the membrane is rated as "〇" (good appearance quality), and when appearance abnormalities are observed the membrane is rated as "×" (poor appearance quality).

[0062] The appearance quality of the polymer electrolyte membranes was good in Examples 1 to 3. This was because the "moisture content adjustment effect" was rated as "good," and water was effectively permeated into the polymer electrolyte membrane M before the catalyst ink was ejected, thereby enabling precise control of the moisture content of the highly hygroscopic polymer electrolyte membrane M.

[0063] In particular, Examples 1 and 2 achieved better appearance quality than Example 3. This is thought to be because the water content in the mixed solution was not too high, but was within an appropriate range. A preferred water content in the mixed solution is, for example, 0.5% to 10%.

[0064] The appearance quality of the polymer electrolyte membranes was not good in Comparative Examples 1 to 4. This is thought to be because the "moisture content adjustment effect" was poor, and water could not be effectively permeated into the polymer electrolyte membrane M before the catalyst ink was ejected, or because even if water was permeated, other excess substances (e.g., toluene) remained in excess.

[0065] Deformation due to swelling occurred in Comparative Examples 1, 2, and 4. Whitening occurred in Comparative Example 3, where the area where the catalyst ink was ejected turned whiter than other areas. This whitening is thought to have occurred because the toluene contained in Chemical Solution 1 and the 3-methoxybutyl acetate contained in Chemical Solution 2 both have slow dissolution rates and low miscibility with water.

[0066] 1, the manufacturing apparatus 2 of this embodiment feedback-controls the discharge of the mixed chemical liquid by the chemical liquid discharge unit 6 based on the detection results of the two detection units 8 and 9. This control method will be described with reference to FIG.

[0067] FIG. 5 is a graph showing an example of the detection results obtained by the detectors 8 and 9 of this embodiment.

[0068] 5 shows the measurement results when the detectors 8 and 9 are infrared absorption spectrometers. The horizontal axis indicates wavelength (unit: μm), and the vertical axis indicates infrared transmittance (unit: %).

[0069] 5, two detection results, waveform 1 and waveform 2, were measured. Waveform 1 is the detection result of first detection unit 8, and waveform 2 is the detection result of second detection unit 9.

[0070] Waveform 1, which is the detection result of first detection unit 8, represents the surface state of the polymer electrolyte membrane M in a state where the mixed chemical solution has been applied. Waveform 1 represents the amounts of multiple components related to water, which is a component of the mixed chemical solution, and other substances (e.g., ethanol, 3-methoxy-3-methyl-1-butanol). Because the transmittance of each component varies depending on the wavelength, by specifying in advance the wavelength at which the component amount for each substance changes significantly, the content of a specific substance can be accurately determined based on the transmittance of that wavelength.

[0071] Waveform 2, which is the detection result of the second detection unit 9, represents the surface state of the polymer electrolyte membrane M before the mixed chemical solution is applied, and mainly represents the amount of water. By identifying in advance the wavelength at which the amount of water changes significantly, it is possible to accurately determine the amount of water contained (moisture content) based on the transmittance of that wavelength.

[0072] For example, the amounts of multiple substances in the polymer electrolyte membrane M before and after the mixed chemical solution is discharged can be determined based on the differences A, B, and C in the transmittance at specific wavelengths between waveform 1 and waveform 2. For example, if the transmittance of water changes significantly at the wavelength to which difference A belongs, but the transmittance of other components does not change significantly, the change in the water content associated with the discharge of the mixed chemical solution can be accurately determined based on the value of difference A. Furthermore, if the transmittance of substances other than water contained in the mixed chemical solution changes significantly at the wavelength to which differences B and C belong, but the transmittance of water does not change significantly, the change in the content of the substance associated with the discharge of the mixed chemical solution can be accurately determined based on the values ​​of differences B and C, respectively.

[0073] Based on waveforms 1 and 2, which are the detection results of the two detection units 8 and 9, the amounts of water and other substances contained in the mixed chemical solution can be identified.

[0074] The control unit 10 of this embodiment controls the mixing amounts of chemical solution 1 and chemical solution 2 in the mixed chemical solution based on the detected component amounts of multiple substances. For example, threshold values ​​for the differences A, B, and C are respectively determined in advance, and the amounts of chemical solution supplied by the two chemical solution supply units 16 and 18 are controlled depending on whether the differences A, B, and C are larger than the respective threshold values.

[0075] For example, when difference A indicates the amount of water content or increase, if difference A is greater than a threshold value, it can be determined that the amount of water content or increase is large, and therefore control may be performed to reduce the supply amount of the first chemical liquid containing water from first chemical liquid supply unit 16. Conversely, if difference A is smaller than the threshold value, control may be performed to increase the supply amount of the first chemical liquid containing water from first chemical liquid supply unit 16.

[0076] For example, when difference B indicates the content or increase of a substance (e.g., alcohol) contained in chemical liquid 1 that evaporates quickly, if difference B is greater than a threshold value, it can be determined that the content or increase of the substance is large, and therefore control may be performed to reduce the supply amount of the first chemical liquid from first chemical liquid supply unit 16. Conversely, if difference B is smaller than the threshold value, control may be performed to increase the supply amount of the first chemical liquid from first chemical liquid supply unit 16.

[0077] For example, when difference C indicates the content or increase of a substance (e.g., 3-methoxy-3-methyl-1-butanol) contained in chemical liquid 2 that has a slow evaporation rate, if difference C is greater than a threshold value, it can be determined that the content or increase of the substance is large, and therefore control may be performed to reduce the supply amount of the second chemical liquid from second chemical liquid supply unit 18. Conversely, if difference C is smaller than the threshold value, control may be performed to increase the supply amount of the second chemical liquid from second chemical liquid supply unit 18.

[0078] The control unit 10 controls the amount of the first chemical liquid supplied by the first chemical liquid supply unit 16 and the amount of the second chemical liquid supplied by the second chemical liquid supply unit 18 based on the results of comparing each of the differences A, B, and C with a threshold value.

[0079] According to the above control method, the water content of the surface of the polymer electrolyte membrane M immediately before the catalyst ink is ejected can be maintained within an appropriate range by feedback-controlling the ejection of the mixed chemical solution by the chemical solution ejection unit 6 based on the detection results of the detection units 8 and 9. This leads to further improvement in the appearance quality of the polymer electrolyte membrane M after the catalyst ink is ejected.

[0080] [Effects, etc.] As described above, the catalyst layer-coated polymer electrolyte membrane manufacturing apparatus 2 of the embodiment is a manufacturing apparatus for manufacturing a catalyst layer-coated electrolyte membrane by applying a catalyst ink to the surface of a polymer electrolyte membrane M, and includes a conveying unit 3 that conveys the polymer electrolyte membrane M in a conveying direction A1 along the longitudinal direction perpendicular to the width direction, a catalyst ink ejection unit 4 that ejects the catalyst ink onto the surface of the polymer electrolyte membrane M, and a chemical solution ejection unit 6 that ejects a mixed chemical solution onto the surface of the polymer electrolyte membrane M at a position upstream of the catalyst ink ejection unit 4 in the conveying direction A1, the mixed chemical solution including a first chemical solution containing at least water and a second chemical solution containing a liquid whose evaporation rate is slower than that of water.

[0081] According to this configuration, by discharging a mixed chemical liquid obtained by mixing the first and second chemical liquids at discharge position P2 upstream of discharge position P1 of the catalyst ink, it is possible to apply the catalyst ink to a pre-wetted polymer electrolyte membrane M, which suppresses deformation of the highly hygroscopic polymer electrolyte membrane M due to a sudden change in water content, and improves the appearance quality of the polymer electrolyte membrane M. In particular, by increasing the water content of the polymer electrolyte membrane M with the first chemical liquid containing at least water, and mixing in the second chemical liquid containing a liquid whose evaporation rate is slower than that of water, evaporation of the first chemical liquid is suppressed, making it easier for water to penetrate into the polymer electrolyte membrane M, and thereby making it easier to achieve the effect of improving and adjusting the water content.

[0082] Furthermore, the catalyst layer-equipped polymer electrolyte membrane manufacturing apparatus 2 of the embodiment further includes a first detection unit 8 that detects the amount of substance components on the surface of the polymer electrolyte membrane M onto which the mixed chemical liquid has been discharged, and a control unit 10. The control unit 10 controls the mixing amounts of the first and second chemical liquids in the mixed chemical liquid based on the detection result of the first detection unit 8. With this configuration, the amount of substance components on the surface of the polymer electrolyte membrane M after the catalyst ink has been discharged can be detected, and the mixing ratio of the first and second chemical liquids can be adjusted based on the result, making it easier to maintain the water content on the surface of the polymer electrolyte membrane M within an appropriate range, leading to improved appearance quality of the polymer electrolyte membrane M.

[0083] Furthermore, in the catalyst-coated polymer electrolyte membrane manufacturing apparatus 2 of the embodiment, the chemical solution discharge unit 6 further includes a second detection unit 9 that detects at least the amount of water on the surface of the polymer electrolyte membrane M before the mixed chemical solution is discharged, and the control unit 10 controls the amount of mixing based on the detection results of the first detection unit 8 and the second detection unit 9. With this configuration, it is possible to compare the surface conditions of the polymer electrolyte membrane M before and after the discharge of the mixed chemical solution, thereby making it possible to adjust the water content with greater precision, leading to an improvement in the appearance quality of the polymer electrolyte membrane M.

[0084] Furthermore, in the catalyst-coated polymer electrolyte membrane manufacturing apparatus 2 of the embodiment, the chemical solution discharge unit 6 has a first chemical solution supply unit 16 that supplies a first chemical solution and a second chemical solution supply unit 18 that supplies a second chemical solution, and the control unit 10 controls the mixing amount by controlling the amount of chemical solution supplied by the first chemical solution supply unit 16 and / or the second chemical solution supply unit 18. With this configuration, the mixing amount can be controlled with a simple configuration and method.

[0085] Furthermore, in the catalyst-coated polymer electrolyte membrane manufacturing apparatus 2 of the embodiment, the first chemical liquid further contains a liquid having a solubility in water of 100 mg / L or more and an evaporation rate of more than 38 when the evaporation rate of butyl acetate is taken as 100. With this configuration, the first chemical liquid, in a mixed state of water and the liquid, is more likely to permeate into the polymer electrolyte membrane M.

[0086] In the catalyst-coated polymer electrolyte membrane manufacturing apparatus 2 of the embodiment, the liquid contained in the first chemical solution has a solubility in water of 1.00×106 mg / L. With this configuration, the first chemical solution, in a mixed state with water, easily permeates into the polymer electrolyte membrane M.

[0087] In the catalyst-coated polymer electrolyte membrane manufacturing apparatus 2 of the embodiment, the liquid contained in the first chemical solution is any one of methanol, ethanol, isopropyl alcohol, n-propyl alcohol, isobutyl alcohol, n-butyl alcohol, propylene glycol, methyl ether, acetone, methyl ethyl ketone, ethyl acetate, and propyl acetate. With this configuration, the first chemical solution is more likely to penetrate the polymer electrolyte membrane M in a mixed state with water.

[0088] In the catalyst layer-provided polymer electrolyte membrane manufacturing apparatus 2 of the embodiment, the liquid contained in the second chemical liquid has a solubility in water of 100 mg / L or more. With this configuration, the first and second chemical liquids can easily permeate the polymer electrolyte membrane M in a mixed state.

[0089] Furthermore, in the catalyst-coated polymer electrolyte membrane manufacturing apparatus 2 of the embodiment, the liquid contained in the second chemical solution has a solubility in water of 1.00×106 mg / L and an evaporation rate lower than 38 when the evaporation rate of butyl acetate is set to 100. With this configuration, the water of the first chemical solution and the water of the second chemical solution can easily permeate the polymer electrolyte membrane M in a mixed state.

[0090] In the catalyst-coated polymer electrolyte membrane manufacturing apparatus 2 of the embodiment, the liquid contained in the second chemical liquid is any one of dipropylene glycol methyl ether, propylene glycol n-propyl ether, dipropylene glycol n-propyl ether, diethylene glycol methyl ether, ethylene glycol n-propyl ether, ethylene glycol n-butyl ether, ethylene glycol t-butyl ether, 3-methoxy-3-methyl-1-butanol, ethylene glycol n-butyl ether acetate, propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, propylene glycol diacetate, dicyclohexanone, diacetone alcohol, and isophorone. This configuration allows the first and second chemical liquids to easily permeate the polymer electrolyte membrane M in a mixed state.

[0091] In the catalyst-coated polymer electrolyte membrane manufacturing apparatus 2 of the embodiment, the first detector 8 and the second detector 9 each include an infrared absorption spectrometer. With this configuration, the amounts of water and liquid components can be detected with high accuracy.

[0092] (Modification of the embodiment) In the embodiment, a case where a second detection unit 9 is provided in addition to a first detection unit 8 is described, but this is not limited to such a case, and it is also possible to omit the second detection unit 9 and provide only the first detection unit 8.

[0093] In the embodiment, the detection units 8 and 9 have infrared absorption spectrometers and detect the component amounts of each substance using infrared rays, but the invention is not limited to this. Any other type of device may be used as long as it can detect the component amounts of water or other substances. For example, the component amounts of each substance can be detected even when electrical resistance or high frequency is used instead of infrared rays.

[0094] Any of the various embodiments or modifications described above can be combined appropriately to achieve the effects of each. In addition, combinations of embodiments, combinations of examples, or combinations of embodiments and examples are possible, and combinations of features from different embodiments or examples are also possible.

[0095] Although the present disclosure has been fully described in connection with the preferred embodiments with reference to the accompanying drawings, various changes and modifications will be apparent to those skilled in the art, and such changes and modifications are to be understood as being included within the scope of the present disclosure as defined by the appended claims unless they depart therefrom.

[0096] (Addendum) According to a first aspect of the present disclosure, there is provided a manufacturing apparatus for manufacturing a catalyst-layered electrolyte membrane by applying a catalyst ink to the surface of a polymer electrolyte membrane, the manufacturing apparatus comprising: a transport unit that transports the polymer electrolyte membrane in a transport direction along a longitudinal direction perpendicular to a width direction; a catalyst ink discharge unit that discharges the catalyst ink onto the surface of the polymer electrolyte membrane; and a chemical solution discharge unit that discharges a mixed chemical solution onto the surface of the polymer electrolyte membrane at a position upstream of the catalyst ink discharge unit in the transport direction, wherein the mixed chemical solution includes a first chemical solution containing at least water and a second chemical solution containing a liquid whose evaporation rate is slower than that of water.

[0097] According to a second aspect of the present disclosure, there is provided the apparatus for manufacturing an electrolytic membrane with a catalyst layer according to the first aspect, further comprising a first detection unit that detects the amount of a substance component on the surface of the polymer electrolyte membrane onto which the mixed chemical solution has been discharged, and a control unit, wherein the control unit controls the mixing amount of the first chemical solution and the second chemical solution in the mixed chemical solution based on the detection result of the first detection unit.

[0098] According to a third aspect of the present disclosure, there is provided the apparatus for manufacturing a catalyst layer-equipped electrolytic membrane according to the second aspect, wherein the chemical solution discharge unit further includes a second detection unit that detects at least the amount of water on the surface of the polymer electrolyte membrane before the mixed chemical solution is discharged, and the control unit controls the mixed amount based on the detection result of the first detection unit and the detection result of the second detection unit.

[0099] According to a fourth aspect of the present disclosure, there is provided the apparatus for manufacturing a catalyst layer-equipped electrolytic membrane according to the second or third aspect, wherein the chemical solution discharge unit has a first chemical solution supply unit that supplies the first chemical solution and a second chemical solution supply unit that supplies the second chemical solution, and the control unit controls the mixing amount by controlling the amount of chemical solution supplied by the first chemical solution supply unit and / or the second chemical solution supply unit.

[0100] According to a fifth aspect of the present disclosure, there is provided the apparatus for manufacturing a catalyst-layered electrolytic membrane according to any one of the first to fourth aspects, wherein the first chemical liquid further contains a liquid having a solubility in water of 100 mg / L or more and an evaporation rate of more than 38 when the evaporation rate of butyl acetate is taken as 100.

[0101] According to a sixth aspect of the present disclosure, there is provided an apparatus for manufacturing an electrolytic membrane with a catalyst layer according to any one of the first to fifth aspects, wherein the liquid of the first chemical solution has a solubility in water of 1.00×10^6 mg / L.

[0102] According to a seventh aspect of the present disclosure, there is provided the apparatus for manufacturing a catalyst layer-equipped electrolytic membrane according to any one of the first to sixth aspects, wherein the liquid of the first chemical solution is any one of methanol, ethanol, isopropyl alcohol, n-propyl alcohol, isobutyl alcohol, n-butyl alcohol, methyl ether of propylene glycol, acetone, methyl ethyl ketone, ethyl acetate, and propyl acetate.

[0103] According to an eighth aspect of the present disclosure, there is provided the apparatus for manufacturing a catalyst-layered electrolytic membrane according to any one of the first to seventh aspects, wherein the liquid of the second chemical solution has a solubility in water of 100 mg / L or more and an evaporation rate of less than 38 when the evaporation rate of butyl acetate is taken as 100.

[0104] According to a ninth aspect of the present disclosure, there is provided the apparatus for manufacturing a catalyst layer-equipped electrolytic membrane according to the eighth aspect, wherein the liquid of the second chemical solution has a solubility in water of 1.00×10^6 mg / L.

[0105] According to a tenth aspect of the present disclosure, there is provided the apparatus for manufacturing a catalyst-layered electrolytic membrane according to any one of the first to ninth aspects, wherein the liquid of the second chemical solution is any one of dipropylene glycol methyl ether, propylene glycol n-propyl ether, dipropylene glycol n-propyl ether, diethylene glycol methyl ether, ethylene glycol n-propyl ether, ethylene glycol n-butyl ether, ethylene glycol t-butyl ether, 3-methoxy-3-methyl-1-butanol, ethylene glycol n-butyl ether acetate, propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, propylene glycol diacetate, dicyclohexanone, diacetone alcohol, and isophorone.

[0106] According to an eleventh aspect of the present disclosure, there is provided the apparatus for manufacturing an electrolytic membrane with a catalyst layer according to any one of the second to fourth aspects, wherein the first detection unit detects the amounts of the plurality of components using any one of infrared rays, electrical resistance, and high frequency.

[0107] According to a twelfth aspect of the present disclosure, there is provided the apparatus for producing a catalyst layer-equipped electrolytic membrane according to any one of the second to fourth aspects, wherein the first detection unit has an infrared absorption spectrometer. [Industrial Applicability]

[0108] The present disclosure is applicable to an apparatus for manufacturing an electrolyte membrane with a catalyst layer. [Explanation of symbols]

[0109] 2. Manufacturing equipment (for electrolyte membranes with catalyst layers) 3. Conveyor 4. Catalyst ink ejection section 6. Chemical solution discharge section 8 First detection unit 9 Second detection unit 10 Control Unit 12 First chemical source 14 Second chemical source 16 First chemical supply unit 18 Second chemical supply unit 20 Discharge part A1 Conveying direction M Polymer electrolyte membrane

Claims

1. A manufacturing apparatus for manufacturing a catalyst-coated electrolyte membrane by applying a catalyst ink to a surface of a polymer electrolyte membrane, comprising: a conveying section that conveys the polymer electrolyte membrane in a conveying direction along a longitudinal direction perpendicular to the width direction; a catalyst ink ejection unit that ejects catalyst ink onto the surface of the polymer electrolyte membrane; a chemical solution discharge unit that discharges a mixed chemical solution onto the surface of the polymer electrolyte membrane at a position upstream of the catalyst ink discharge unit in the transport direction, The mixed chemical solution includes a first chemical solution containing at least water, and a second chemical solution containing a liquid having an evaporation rate slower than that of water.

2. a first detection unit that detects the amount of a substance component on the surface of the polymer electrolyte membrane onto which the mixed chemical solution is discharged; a control unit, 2. The manufacturing apparatus for a catalyst-coated electrolyte membrane according to claim 1, wherein the control unit controls the mixing amounts of the first chemical liquid and the second chemical liquid in the mixed chemical liquid based on the detection result of the first detection unit.

3. the chemical solution discharge unit further includes a second detection unit that detects at least the amount of water on the surface of the polymer electrolyte membrane before the mixed chemical solution is discharged, 3. The apparatus for manufacturing a catalyst-coated electrolyte membrane according to claim 2, wherein the control unit controls the mixing amount based on the detection result of the first detection unit and the detection result of the second detection unit.

4. the chemical liquid discharge unit includes a first chemical liquid supply unit that supplies the first chemical liquid and a second chemical liquid supply unit that supplies the second chemical liquid; 3. The manufacturing apparatus for a catalyst-coated electrolyte membrane according to claim 2, wherein the control unit controls the mixing amount by controlling the amount of chemical solution supplied by the first chemical solution supply unit and / or the second chemical solution supply unit.

5. 2. The apparatus for manufacturing a catalyst-coated electrolyte membrane according to claim 1, wherein the first chemical solution further contains a liquid having a solubility in water of 100 mg / L or more and an evaporation rate of more than 38, where the evaporation rate of butyl acetate is taken as 100.

6. 6. The apparatus for manufacturing a catalyst-coated electrolyte membrane according to claim 5, wherein the liquid of the first chemical solution has a solubility in water of 1.00 x 10^6 mg / L.

7. 6. The apparatus for manufacturing a catalyst-coated electrolyte membrane according to claim 5, wherein the liquid of the first chemical solution is any one of methanol, ethanol, isopropyl alcohol, n-propyl alcohol, isobutyl alcohol, n-butyl alcohol, methyl ether of propylene glycol, acetone, methyl ethyl ketone, ethyl acetate, and propyl acetate.

8. 2. The apparatus for manufacturing a catalyst-coated electrolyte membrane according to claim 1, wherein the liquid of the second chemical solution has a solubility in water of 100 mg / L or more and an evaporation rate of the second chemical solution that is lower than 38 times the evaporation rate of butyl acetate, where the evaporation rate of the second chemical solution is taken as 100.

9. 9. The apparatus for manufacturing a catalyst-coated electrolyte membrane according to claim 8, wherein the liquid of the second chemical solution has a solubility in water of 1.00 x 10^6 mg / L.

10. 2. The apparatus for manufacturing a catalyst-coated electrolyte membrane according to claim 1, wherein the liquid of the second chemical solution is any one of dipropylene glycol methyl ether, propylene glycol n-propyl ether, dipropylene glycol n-propyl ether, diethylene glycol methyl ether, ethylene glycol n-propyl ether, ethylene glycol n-butyl ether, ethylene glycol t-butyl ether, 3-methoxy-3-methyl-1-butanol, ethylene glycol n-butyl ether acetate, propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, propylene glycol diacetate, dicyclohexanone, diacetone alcohol, and isophorone.

11. 3. The apparatus for manufacturing a catalyst-coated electrolyte membrane according to claim 2, wherein the first detection unit detects the amounts of the plurality of components using any one of infrared rays, electrical resistance, and high frequency.

12. 3. The apparatus for manufacturing a catalyst-coated electrolyte membrane according to claim 2, wherein the first detection unit has an infrared absorption spectrometer.

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