WO2019230610A1 - Transfer sheet for transferring layer and sheet with electrode catalyst layer - Google Patents

Transfer sheet for transferring layer and sheet with electrode catalyst layer Download PDF

Info

Publication number
WO2019230610A1
WO2019230610A1 PCT/JP2019/020763 JP2019020763W WO2019230610A1 WO 2019230610 A1 WO2019230610 A1 WO 2019230610A1 JP 2019020763 W JP2019020763 W JP 2019020763W WO 2019230610 A1 WO2019230610 A1 WO 2019230610A1
Authority
WO
WIPO (PCT)
Prior art keywords
layer
transfer sheet
transfer
electrode catalyst
sheet
Prior art date
Application number
PCT/JP2019/020763
Other languages
French (fr)
Japanese (ja)
Inventor
裕太 黒木
Original Assignee
日東電工株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 日東電工株式会社 filed Critical 日東電工株式会社
Priority to KR1020207037340A priority Critical patent/KR20210018319A/en
Priority to CN201980036413.6A priority patent/CN112203855A/en
Publication of WO2019230610A1 publication Critical patent/WO2019230610A1/en

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
    • B32B27/304—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers comprising vinyl halide (co)polymers, e.g. PVC, PVDC, PVF, PVDF
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
    • B32B5/18—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by features of a layer of foamed material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
    • B32B5/22—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed
    • B32B5/32—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed at least two layers being foamed and next to each other
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
    • B32B7/04—Interconnection of layers
    • B32B7/06—Interconnection of layers permitting easy separation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/88—Processes of manufacture
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/10—Fuel cells with solid electrolytes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells

Definitions

  • the present invention relates to a transfer sheet for transferring a layer, and more specifically to a transfer sheet that can be used for supporting and transferring an electrode catalyst layer provided in an electrochemical element such as a fuel cell.
  • the present invention also relates to a sheet with an electrode catalyst layer.
  • a membrane electrode assembly (MEA) is used as a main component.
  • the MEA usually includes an electrolyte membrane and an electrode catalyst layer. More specifically, a pair of electrode catalyst layers for the fuel electrode and the air electrode are respectively laminated on the main surfaces of the electrolyte membrane.
  • An MEA configuration in which a diffusion layer is further formed on the surface of the electrode catalyst layer is also employed.
  • One method of laminating the electrode catalyst layer on the electrolyte membrane is a transfer method.
  • a sheet carrying the electrode catalyst layer on the surface is prepared, and the electrode catalyst layer is thermally transferred to the electrolyte membrane using the sheet as a transfer sheet.
  • Patent Document 1 a belt-shaped electrolyte membrane and a belt-shaped sheet carrying an electrode catalyst layer are laminated to form a laminate, and after passing between a pair of heated thermal transfer rolls, the sheet is peeled off, A method is disclosed in which a catalyst layer is continuously thermally transferred to an electrolyte membrane.
  • Patent Document 2 discloses a method in which an electrode catalyst layer formed on a base material is bonded to a polymer electrolyte membrane by hot pressing, and then the base material is peeled off to thermally transfer the electrode catalyst layer to the electrolyte membrane. Yes.
  • the electrode catalyst layer is becoming thinner with the miniaturization of fuel cells.
  • the thinned electrode catalyst layer is required to improve the homogeneity in the in-plane direction of the MEA, as compared with the prior art.
  • the homogeneity in the state transferred to the electrolyte membrane has a great influence on the power generation characteristics of the fuel cell.
  • an increase in thermal transfer temperature for the purpose of reliably transferring the thinned electrode catalyst layer to the electrolyte membrane is assumed.
  • defects such as deformation, cracks, and loss tend to occur in the electrode catalyst layer after transfer as the thermal transfer temperature rises.
  • An object of the present invention is to provide a transfer sheet that can satisfactorily perform thermal transfer of a transferred layer even when the thermal transfer temperature is high.
  • the present invention A transfer sheet for transferring the layer, A base material layer, and a pair of fluororesin porous layers that are bonded to the base material layer and sandwich the base material layer, A transfer sheet in which at least one of the fluororesin porous layers has a cohesive force of 1.8 N / 20 mm or more, I will provide a.
  • the present invention provides: The transfer sheet of the present invention, and an electrode catalyst layer,
  • the electrode catalyst layer is disposed on the at least one fluororesin porous layer, a sheet with an electrode catalyst layer, I will provide a.
  • the support surface of the transfer layer is constituted by the fluororesin porous layer.
  • the fluororesin constituting the fluororesin porous layer has a high releasability.
  • the contact area with the transfer layer on the carrying surface can be reduced as compared with the non-porous layer. For this reason, in the transfer sheet of the present invention, high releasability of the transfer layer during thermal transfer is ensured.
  • the surface of the fluororesin porous layer having a high cohesive force can be used as the carrying surface of the transfer layer.
  • the cohesive force corresponds to the breaking strength of the layer in the thickness direction.
  • the transfer sheet of the present invention has a structure in which the base material layer is sandwiched between a pair of fluororesin porous layers. For this reason, the deformation
  • the extension of the transfer sheet at the time of thermal transfer is suppressed by the base material layer as compared with the case where it is composed only of the fluororesin porous layer.
  • the transfer sheet of the present invention even when the thermal transfer temperature is high, the transfer layer can be favorably thermally transferred.
  • the transfer sheet 10 includes a base material layer 1 and a pair of fluororesin porous layers 2 a and 2 b that sandwich the base material layer 1.
  • the transfer sheet 10 is a transfer sheet for transferring a transfer layer formed and supported thereon to another member.
  • one fluororesin porous layer 2a has a cohesive force of 1.8 N / 20 mm or more.
  • the support surface of the transfer layer can be constituted by the fluororesin porous layer 2a. More specifically, the main surface (exposed surface) 21 opposite to the side in contact with the base material layer 1 in the fluororesin porous layer 2a can be used as a transfer layer support surface.
  • both the main surface 21 and the main surface 22 may be used as the transfer layer carrying surface.
  • the cohesive force of the fluororesin porous layer corresponds to the breaking strength of the layer in the thickness direction. That is, the higher the cohesive force, the harder the fluororesin porous layer is destroyed by the force applied in the thickness direction.
  • the lower limit of the cohesive force of the fluororesin porous layer 2a may be 1.9 N / 20 mm or more, and further 2.0 N / 20 mm or more.
  • the upper limit of the cohesive force of the fluororesin porous layer 2a is, for example, 4.5 N / 20 mm or less, and may be 4.0 N / 20 mm or less, 3.5 N / 20 mm or less, or even 3.0 N / 20 mm or less. .
  • the cohesive force of the fluororesin porous layer can be evaluated by a 180 ° peeling test.
  • the cohesive force of the fluororesin porous layer can be controlled by characteristics such as the average pore diameter, thickness, and membrane weight per unit area of the fluororesin porous layer. Moreover, each characteristic of a fluororesin porous layer can be controlled by the manufacturing conditions of a fluororesin porous layer, for example, the extending conditions for forming a fluororesin porous layer.
  • the thickness of the fluororesin porous layer 2a is, for example, 100 ⁇ m or less, and may be 70 ⁇ m or less, 50 ⁇ m or less, 40 ⁇ m or less, 30 ⁇ m or less, 20 ⁇ m or less, or even 10 ⁇ m or less.
  • the thickness of the fluororesin porous layer 2a decreases, the degree of unevenness on the carrying surface tends to decrease.
  • the lower limit of the thickness of the fluororesin porous layer 2a is, for example, 3 ⁇ m or more, 4 ⁇ m or more, and further 5 ⁇ m or more.
  • the thickness of the fluororesin porous layer can be evaluated by analyzing the cross-sectional image of the transfer sheet.
  • the example of a cross-sectional image is an enlarged observation image by an optical microscope or an electron microscope with respect to the cross section of the transfer sheet.
  • the magnification of the magnified observation image may be about 500 times, for example.
  • the thickness at at least 10 measurement points is evaluated while changing the location.
  • the average value of the thickness at each evaluated measurement point can be the thickness of the fluororesin porous layer.
  • the cohesive force of the fluororesin porous layer 2b may be within the range of the cohesive force of the fluororesin porous layer 2a described above.
  • the thickness of the fluororesin porous layer 2b may be within the range of the thickness of the fluororesin porous layer 2a described above.
  • the fluororesin porous layer 2b may have a cohesive force of 1.8 N / 20 mm or more and / or a thickness of 100 ⁇ m or less.
  • the cohesive force and / or thickness of the pair of fluororesin porous layers 2a and 2b provided in the transfer sheet 10 may be the same. This configuration is suitable for the case where the transfer sheet 10 is reused with the main surface 22 as the support surface after the main surface 21 is used as the support surface. Further, when the fluororesin porous layers 2a and 2b have the same thickness, deformation of the transfer sheet 10 due to heat of thermal transfer, typically curl, can be more reliably suppressed. For this reason, even when the thermal transfer temperature is high, thermal transfer of the transfer layer by the transfer sheet 10 can be more satisfactorily performed.
  • the pair of fluororesin porous layers 2a and 2b included in the transfer sheet 10 may have the same configuration.
  • the transfer layer transferred by the transfer sheet 10 is, for example, an electrode catalyst layer used for an electrochemical element such as a fuel cell.
  • the example of an electrode catalyst layer is an electrode catalyst layer with which MEA is provided.
  • the electrode catalyst layer includes a precursor layer thereof.
  • the transfer layer transferred by the transfer sheet 10 is not limited to the electrode catalyst layer.
  • the electrode catalyst layer on the transfer sheet 10 is usually formed by applying a catalyst solution containing a catalyst electrode and a diffusion solvent to the carrying surface of the transfer sheet 10.
  • a catalyst solution having a low solid content concentration and / or a low viscosity is generally used to form a thin electrode catalyst layer.
  • the carrying surface of the transfer sheet 10 is porous. For this reason, even when a catalyst solution having a low solid content concentration and / or a low viscosity is used, the catalyst solution is less likely to be repelled than a non-porous support surface, and the coating property of the catalyst solution can be improved. When the coatability is improved, for example, an electrode catalyst layer having higher homogeneity in the in-plane direction can be formed. Therefore, the transfer sheet 10 has high merit as an electrode catalyst layer transfer sheet (electrode catalyst layer transfer sheet), in particular, a thin electrode catalyst layer transfer sheet.
  • the fluororesin porous layers 2a and 2b and the base material layer 1 are joined by fusion bonding. Bonding by fusion is suitable for forming the transfer sheet 10 having a uniform thickness and reducing the manufacturing cost of the transfer sheet 10.
  • the fusion between the fluororesin porous layers 2a and 2b and the base material layer 1 can be performed by, for example, thermal lamination or hot pressing.
  • the fluororesin porous layers 2a and 2b and the base material layer 1 are fused by pressing a hot roll maintained at 130 to 290 ° C. with a linear pressure of 10 to 40 N / m.
  • the line speed at this time varies depending on the hot roll diameter, the heating temperature, and the like, but is, for example, 3.0 to 20.0 m / min.
  • the method of fusing the fluororesin porous layers 2a and 2b and the base material layer 1 is not limited to the above example.
  • the form of bonding between the fluororesin porous layers 2a and 2b and the base material layer 1 is not limited to fusion.
  • the fluororesin porous layers 2a and 2b and the base material layer 1 may be joined by, for example, an adhesive or a pressure-sensitive adhesive.
  • the thickness of the transfer sheet 10 is, for example, 15 ⁇ m to 400 ⁇ m, and may be 50 ⁇ m to 300 ⁇ m.
  • the base material layer 1 also serves as a reinforcing layer for the fluororesin porous layers 2 a and 2 b in the transfer sheet 10.
  • the base material layer 1 serves as a reinforcing layer for the fluororesin porous layers 2 a and 2 b in the transfer sheet 10.
  • Handleability includes transportability.
  • transfer of the transfer layer by roll-to-roll using the belt-shaped transfer sheet 10 supplied from the roll can be more stably and reliably performed.
  • the base material layer 1 is, for example, a resin layer, a metal layer, a paper layer, or an inorganic layer.
  • the transfer layer is an electrode catalyst layer
  • the base material layer 1 which is a resin layer, particularly a thermoplastic resin layer, is preferable from the viewpoint of preventing the metal from being mixed into the electrode catalyst layer.
  • the fluororesin porous layer is excluded from the resin layer.
  • the metal constituting the base material layer 1 is, for example, aluminum or stainless steel.
  • the melting point of the thermoplastic resin constituting the base material layer 1 is preferably 280 ° C. or lower.
  • the base material layer 1 composed of a thermoplastic resin having a melting point of 280 ° C. or less has good fusion properties with the fluororesin porous layers 2a and 2b.
  • the thermoplastic resin are at least one selected from polyester, polyacetal, polyethylene, ultrahigh molecular weight polyethylene, and polypropylene.
  • polyesters are polyethylene terephthalate (PET) and polybutylene terephthalate.
  • PET polyacetal and PET are preferable, and PET is more preferable because it hardly changes in quality when fused to the fluororesin porous layers 2a and 2b and is excellent in heat resistance and chemical resistance.
  • PET is preferably a grade having a low softening temperature, and in particular, a grade that starts softening at a temperature lower than 233 ° C. is preferable.
  • the base material layer 1 is typically a non-porous layer.
  • the non-porous base material layer 1 is suitable for reducing the surface roughness of the main surface 11 facing the fluororesin porous layer 2a.
  • the degree of unevenness on the main surface 21 (supporting surface) of the fluororesin porous layer 2a can be further reduced.
  • the transfer layer can be stably held.
  • the base material layer 1 is not limited to the non-porous layer, and may be a porous layer constituted by, for example, a woven fabric, a nonwoven fabric, a net, a stretched porous film, a fine particle fusion porous film, or the like.
  • the thickness of the base material layer 1 is, for example, 12.5 ⁇ m to 200 ⁇ m, and may be 25 to 175 ⁇ m.
  • the thickness of the base material layer 1 becomes excessively small, the reinforcing effect by the base material layer 1 is reduced, and the strength and / or handleability of the transfer sheet 10 may be reduced.
  • the thickness of the base material layer 1 is excessively large, for example, when the transfer sheet 10 is a roll, the weight of the roll may be excessive.
  • fluororesin constituting the fluororesin porous layers 2a and 2b are polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), and tetrafluoroethylene-hexafluoropropylene copolymer. (FEP).
  • a preferred fluororesin is PTFE.
  • the fluororesin porous layer 2a is preferably a PTFE porous layer. Both the fluororesin porous layers 2a and 2b may be composed of the same fluororesin.
  • the fluororesin porous layers 2a and 2b may not contain components other than the fluororesin, and may not substantially contain components other than the fluororesin. In this specification, “substantially free” means that the content is less than 0.1 wt%, preferably less than 0.01 wt%.
  • the average pore diameter of the fluororesin porous layer 2a is, for example, 0.1 to 20 ⁇ m, and may be 0.2 to 15 ⁇ m, 0.2 to 10 ⁇ m, or even 1.5 to 7.0 ⁇ m.
  • thermal transfer of the transfer layer can be carried out more favorably.
  • the average pore diameter becomes excessively large for example, when the transfer layer is an electrode catalyst layer, carbon particles and catalyst particles contained in the electrode catalyst layer are taken into the pores of the fluororesin porous layer 2a during thermal transfer and thermally transferred.
  • the surface of the transfer layer may become rough.
  • the average pore diameter of both of the fluororesin porous layers 2a and 2b may be in the above range.
  • the average pore diameters of both the fluororesin porous layers 2a and 2b may be the same.
  • the contact angle with water on the main surface 21 of the fluororesin porous layer 2a is, for example, 100 degrees or more, 120 degrees or more, and 130 degrees or more.
  • the main surface having a high contact angle with water is particularly excellent in releasability from the transfer layer.
  • the contact angle with water on the main surface 22 of the fluororesin porous layer 2b may be in the above range.
  • the contact angle with water is a value evaluated by a sessile drop method defined in Japanese Industrial Standard (hereinafter referred to as “JIS”) R3257.
  • JIS R3257 is a standard relating to a method for evaluating the contact angle of the substrate glass surface.
  • the contact angle with water on the main surface of the transfer sheet 10 can be evaluated according to the test conditions defined in this standard.
  • the curl height at the end when the transfer sheet 10 is allowed to stand in an atmosphere of 120 ° C. for 5 minutes is, for example, 10 mm or less, preferably 7 mm or less, more preferably 5 mm or less.
  • An evaluation method of the curl height at the end will be described with reference to FIGS. 3A and 3B show cross sections obtained by cutting the test piece 31 and the plane 32 shown in FIGS. 2A and 2B in the width direction of the test piece 31, respectively.
  • the left-right direction of the paper surface of FIG. “Width” is, for example, the TD direction of the sheet, and in the case of a belt-like sheet, the width direction.
  • “Length” is, for example, the MD direction of the sheet, and in the case of a belt-like sheet, it is the longitudinal direction thereof.
  • a test sheet 31 is obtained by cutting out a transfer sheet, which is an evaluation object, into a width of 490 mm and a length of 500 mm.
  • the test piece 31 is accommodated in a dryer maintained at 120 ° C. and allowed to stand for 5 minutes. At that time, the test piece 31 is allowed to stand on a flat surface 32 that does not cause deformation at 120 ° C. that affects the evaluation of the curl height (FIG. 2 and FIG. 3A).
  • the plane 32 is, for example, the surface of a metal plate. After standing for 5 minutes, the test piece 31 together with the plane 32 is taken out of the dryer and cooled to room temperature. After cooling, the amount of lifting from the plane 32 by standing at 120 ° C.
  • the average value can be the curl height at the end of the transfer sheet 10.
  • the transfer sheet cut out with a smaller size is used as a test piece, and the end of the transfer sheet is measured by the above method.
  • the curl height can be obtained.
  • the coefficient according to the size of the test piece used for the measurement is multiplied by the measurement value, and converted to a value when a test piece having a width of 490 mm ⁇ 500 mm is used for the measurement. This converted value can be the curl height at the end of the transfer sheet.
  • FIG. 4 An example of the sheet with an electrode catalyst layer of the present disclosure is shown in FIG.
  • the sheet 15 with an electrode catalyst layer shown in FIG. 4 is a laminated sheet including the transfer sheet 10 and the transfer layer 3 disposed on the main surface 21 of the fluororesin porous layer 2a in the transfer sheet 10.
  • the transfer layer 3 is an electrode catalyst layer.
  • the sheet 15 with an electrode catalyst layer is configured by laminating a fluororesin porous layer 2b, a base material layer 1, a fluororesin porous layer 2a, and a transfer layer 3 in this order.
  • the transfer sheet 10 provided in the electrode catalyst layer-attached sheet 15 is as described above, including preferred forms.
  • the transfer layer 3 can be thermally transferred to the electrolyte membrane to form the MEA. As shown in FIG. 5, the transfer layer 3 thermally transferred onto the electrolyte membrane 5 becomes the electrode catalyst layer 6 of the MEA 20.
  • MEA An example of a product that can be manufactured using the transfer sheet 10 or the electrode catalyst layer-attached sheet 15 is MEA used for an electrochemical element such as PEFC.
  • the product manufactured using the transfer sheet 10 or the electrode catalyst layer-attached sheet 15 is not limited to the MEA.
  • the electrolyte membrane 5 includes an electrolyte membrane (polymer electrolyte membrane) 5 made of a polymer electrolyte and a pair of electrode catalyst layers 6 that sandwich the electrolyte membrane 5.
  • the electrode catalyst layer 6 is, for example, a porous thin film having pores having a diameter of 1 ⁇ m or less.
  • the electrode catalyst layer 6 mainly contains catalyst material-supporting particles (catalyst particles) and a polymer electrolyte.
  • known polymer electrolytes such as fluorine polymer electrolytes and hydrocarbon polymer electrolytes can be used.
  • the manufacturing method of MEA using the transfer sheet 10 includes, for example, an electrode catalyst layer laminating step, an electrolyte membrane laminating step, a thermocompression bonding step, and a peeling step.
  • the electrode catalyst layer laminating step is a step of forming on the transfer sheet 10 a transfer layer 3 that becomes an electrode catalyst layer after thermal transfer.
  • the electrolyte membrane laminating step is a step of laminating the transfer sheet 10 and the electrolyte membrane 5 so that the transfer layer 3 and the electrolyte membrane 5 are in contact with each other.
  • the thermocompression bonding process is a process in which the transfer layer 3 and the electrolyte membrane 5 are thermocompression bonded.
  • the peeling process is a process of peeling the transfer sheet 10 and leaving the transfer layer 3 on the electrolyte membrane 5 as the electrode catalyst layer 6.
  • the electrolyte membrane lamination step, the thermocompression bonding step, and the peeling step constitute a transfer step for the transfer layer 3.
  • the electrode catalyst layer stacking step can be performed, for example, as follows. First, a catalyst solution (electrode catalyst layer paste) in which catalyst particles and a polymer electrolyte are dispersed in a dispersion solvent is applied to the transfer sheet 10 to form a coating film. Next, the whole is heated at a temperature of about 30 to 180 ° C. to dry the coating film, and a laminated sheet (sheet 15 with the electrode catalyst layer) of the transfer sheet 10 and the transfer layer 3 as the electrode catalyst layer is obtained.
  • a known method such as a doctor blade method, a screen printing method, a roll coating method, or a spray method can be employed.
  • the thermocompression bonding step can be performed by, for example, hot pressing the laminated body in a state where the electrolyte membrane 5 and the transfer layer 3 are in contact with each other or passing them through a pair of hot rolls.
  • the thermocompression bonding temperature is, for example, 80 to 150 ° C. although it depends on the type of the electrolyte membrane 5.
  • the transfer layer 3 may be thermocompression bonded to both surfaces of the electrolyte membrane 5 at the same time.
  • the peeling step can be performed by, for example, continuously peeling the transfer sheet 10 from the thermocompression bonding body of the electrolyte membrane 5 and the transfer layer 3 using a roll for winding the transfer sheet 10.
  • the peeled transfer sheet 10 may be reused.
  • FIG. 6 shows an example of an apparatus that performs the thermocompression bonding process and the peeling process as a series of processes.
  • catalyst materials used for the catalyst particles include platinum group elements such as platinum, palladium, ruthenium, iridium, rhodium, osmium; iron, lead, copper, chromium, cobalt, nickel, manganese, vanadium, molybdenum, gallium, aluminum, etc. Metals; alloys thereof; and oxides and double oxides of these metals. If the particle size of the catalyst particles is too large, the activity of the catalyst is lowered, and if it is too small, the stability of the catalyst is lowered. Therefore, the particle size is preferably 0.5 to 20 nm, more preferably 1 to 5 nm.
  • the catalyst particles composed of one or more metals selected from platinum, gold, palladium, rhodium, ruthenium and iridium are excellent in electrode reactivity. For this reason, the use of the catalyst particles enables an efficient and stable electrode reaction.
  • Carbon particles are suitable for the particles carrying the catalyst substance.
  • the carbon particles are not limited as long as they are in the form of fine particles, have conductivity, and are not exposed to the catalyst.
  • Examples of carbon particles are carbon black, graphite, graphite, activated carbon, carbon fiber, carbon nanotube, and fullerene. If the particle size of the carbon particles is too small, it becomes difficult to form an electron conduction path. If the particle size is too large, the gas diffusibility of the electrode catalyst layer is reduced or the utilization factor of the catalyst is reduced. Preferably, 10 to 100 nm is more preferable.
  • a known material can be used for the polymer electrolyte regardless of the difference in cation conductivity and anion conductivity.
  • the cation conductivity is, for example, proton conductivity.
  • a known fluorine-based polymer electrolyte or hydrocarbon-based polymer electrolyte can be used as the polymer electrolyte having proton conductivity.
  • An example of the fluorine-based polymer electrolyte is Nafion (registered trademark) manufactured by DuPont.
  • hydrocarbon-based polymer electrolyte examples include sulfonated polyether ketone, sulfonated polyethersulfone, sulfonated polyetherethersulfone, sulfonated polysulfide, and sulfonated polyphenylene.
  • the polymer electrolyte constituting the electrolyte membrane and the polymer electrolyte contained in the electrode catalyst layer are preferably the same.
  • the dispersion solvent used for the catalyst solution is not limited as long as the polymer electrolyte can be dissolved or dispersed as a fine gel in a highly fluid state without eroding the catalyst particles.
  • the dispersion solvent include alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butyl alcohol, and pentaanol; acetone Ketone solvents such as methyl ethyl ketone, pentanone, methyl isobutyl ketone, heptanone, cyclohexanone, methyl cyclohexanone, acetonyl acetone, diisobutyl ketone; ether solvents such as tetrahydrofuran, dioxane, diethylene glycol dimethyl ether, anisole, methoxy toluene, dibutyl ether; Formamide, dimethylacet
  • the catalyst solution may contain a dispersant.
  • the dispersant are an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant.
  • sulfonic acid type surfactants such as alkylbenzene sulfonic acid, oil-soluble alkyl benzene sulfonic acid, ⁇ -olefin sulfonic acid, sodium alkyl benzene sulfonate, oil-soluble alkyl benzene sulfonate, ⁇ -olefin sulfonate are used as dispersants. It can be preferably used.
  • Example 1 After 100 parts by weight of PTFE fine powder (Daikin Kogyo Co., Ltd., Polyflon F-104) and 20 parts by weight of a liquid lubricant (n-dodecane, Japan Energy Co., Ltd.) are uniformly mixed and compressed in a cylinder A ram extrusion molding was performed to form a sheet-like PTFE molded body. Next, the formed PTFE compact was passed through a pair of rolling rolls and rolled to a thickness of 0.2 mm. Next, after the rolled PTFE molded body is heated to 150 ° C. to remove the liquid lubricant, it is stretched in the MD direction at a stretching temperature of 370 ° C.
  • PTFE fine powder Daikin Kogyo Co., Ltd., Polyflon F-104
  • a liquid lubricant n-dodecane, Japan Energy Co., Ltd.
  • a PTFE porous layer (thickness 45 ⁇ m, average pore diameter 3.0 ⁇ m, membrane weight 0.00975 g / m 2 per unit area).
  • the thickness of the PTFE porous layer which is a single layer was evaluated with a dial gauge. Specifically, the thickness at at least 10 measurement points was evaluated while changing the location, and the average value of the thicknesses at each measured measurement point was taken as the thickness of the PTFE porous layer.
  • the average pore diameter of the PTFE porous layer was evaluated by a commercially available evaluation apparatus (Perm-Porometer manufactured by Porous Materials, Inc.) capable of automatic measurement in accordance with the method defined in the American Society for Testing and Materials (ASTM) F316-86. .
  • the membrane weight per unit area in the PTFE porous layer was determined by dividing the weight of the PTFE porous layer by the area of the layer. In order to ensure measurement accuracy, the area of the PTFE porous layer for evaluating the membrane weight per unit area was set to 5 m 2 or more.
  • a non-porous PET film (Unitika Ltd., EMBLET® SD-75, film thickness 75 ⁇ m) was prepared as a base material layer, and the prepared base material layer and the prepared PTFE porous layer were paired with each other. Lamination was performed such that the base material layer was sandwiched by the PTFE porous layer. Next, the laminate of the base material layer and the PTFE porous layer was hot-pressed at a linear pressure of 20 kN for 60 seconds with a high-temperature press at 280 ° C., and then formed into a predetermined shape (strip shape having a width of 20 mm and a length of 400 mm).
  • Example 1 Cut to obtain a transfer sheet (Sample 1) in which a PET base material layer and a pair of PTFE porous layers sandwiching the PET base material layer were fused. The cutting was performed so that the MD direction of the PTFE porous layer coincided with the length direction of the strip.
  • Example 2 A PTFE porous layer (thickness 50 ⁇ m, average pore diameter 2.9 ⁇ m, membrane weight 0.01000 g / m 2 per unit area) was prepared in the same manner as Sample 1 except that the stretching conditions were changed. Next, a transfer sheet (Sample 2) in which a PET base material layer and a pair of PTFE porous layers sandwiching the PET base material layer were fused in the same manner as Sample 1 except that the produced PTFE porous layer was used. )
  • Example 3 A PTFE porous layer (thickness 60 ⁇ m, average pore diameter 2.8 ⁇ m, membrane weight 0.01025 g / m 2 per unit area) was prepared in the same manner as Sample 1 except that the stretching conditions were changed. Next, a transfer sheet (Sample 3) in which a PET base material layer and a pair of PTFE porous layers sandwiching the PET base material layer were fused in the same manner as Sample 1 except that the produced PTFE porous layer was used. )
  • Example 4 A PTFE porous layer (thickness 40 ⁇ m, average pore diameter 3.3 ⁇ m, membrane weight 0.00950 g / m 2 per unit area) was prepared in the same manner as Sample 1 except that the stretching conditions were changed. Next, a transfer sheet (Sample 4) in which a PET base material layer and a pair of PTFE porous layers sandwiching the PET base material layer were fused in the same manner as in Sample 1 except that the produced PTFE porous layer was used. )
  • Example 5 Comparative example
  • a PTFE porous layer (thickness 30 ⁇ m, average pore diameter 3.5 ⁇ m, membrane weight 0.00930 g / m 2 per unit area) was prepared in the same manner as Sample 1 except that the stretching conditions were changed.
  • a transfer sheet (comparative example) in which a PET base material layer and a pair of PTFE porous layers sandwiching the PET base material layer were fused in the same manner as in Sample 1 except that the produced PTFE porous layer was used. Sample 5) was obtained.
  • Example 6 Comparative example
  • a PTFE porous layer (thickness 25 ⁇ m, average pore diameter 3.7 ⁇ m, membrane weight 0.00900 g / m 2 per unit area) was prepared in the same manner as Sample 1 except that the stretching conditions were changed.
  • a transfer sheet (comparative example) in which a PET base material layer and a pair of PTFE porous layers sandwiching the PET base material layer were fused in the same manner as in Sample 1 except that the produced PTFE porous layer was used.
  • a sample 6 was obtained.
  • the cohesive force of the PTFE porous layer was evaluated as follows using a 180 ° peeling test.
  • the double-sided adhesive tape 51 (Nitto Denko Co., Ltd., No. 5000NS, 160 ⁇ m in thickness, 20 mm in width and 350 mm in length) is attached to the surface (affixed) of stainless steel Affixed to the wearing surface).
  • the double-sided pressure-sensitive adhesive tape 51 had a sufficient sticking force not to peel from the sticking surface of the fixing plate 52 during the test.
  • the fixing plate 52 which has a flat sticking surface, the area of a sticking surface larger than the area of the double-sided adhesive tape 51, and sufficient thickness which does not deform
  • the fixing plate 52 which has a flat sticking surface, the area of a sticking surface larger than the area of the double-sided adhesive tape 51, and sufficient thickness which does not deform
  • Each sample 53 was affixed on the opposite surface of the double-sided pressure-sensitive adhesive tape 51 to the fixed plate 52 side, with 51 as the “test plate” defined in the above item. The sample 53 was attached such that the PTFE porous layer to be evaluated was in contact with the double-sided adhesive tape 51.
  • the sample 53 was attached by making the long side coincide with the fixed plate 52 and setting the length of the attached portion from one end of the sample 53 to 150 mm.
  • the number of reciprocations of the manual roller (mass 2 kg) for pressing the sample 53 and the double-sided pressure-sensitive adhesive tape 51 does not measure the adhesive force of the double-sided pressure-sensitive adhesive tape 51. Only.
  • the laminate of the fixing plate 52, the double-sided pressure-sensitive adhesive tape 51, and the sample 53 was left in an atmosphere at 70 ° C. for 10 minutes to homogenize the adhesive force of the double-sided pressure-sensitive adhesive tape 51 to the sample 53. Thereafter, the whole was naturally cooled to room temperature (23 ° C. ⁇ 1 ° C.).
  • [Coatability of catalyst solution] (Preparation of catalyst solution) Since the catalyst material used for the electrode catalyst layer is generally expensive, in this example, the applicability of a simulated catalyst solution containing only the carbon particles and the polymer electrolyte was evaluated without the catalyst material. It is considered that the catalyst substance does not greatly affect the coating property of the catalyst solution on the transfer sheet. For this reason, the applicability of the catalyst solution can be evaluated with a simulated catalyst solution.
  • a simulated catalyst solution was prepared as follows. First, 25 g of carbon particles, 125 g of polymer electrolyte (Nafion), 302.5 g of isopropyl alcohol, and 47.5 g of water were mixed to obtain a pseudo catalyst electrode ink having a total amount of 500 g.
  • the obtained pseudo catalyst electrode ink and isopropyl alcohol were mixed and diluted at a weight ratio of 1: 0.5 to obtain a simulated catalyst solution.
  • the composition of this solution corresponds to the low solids concentration and low viscosity composition used to form the thinned electrocatalyst layer.
  • the prepared simulated catalyst solution was applied to the main surface (exposed surface) of one PTFE porous layer in each sample using an applicator to form a coating film (thickness 0.25 mm).
  • the direction of application was the length direction of each sample.
  • the whole was heated for 3 minutes using a dryer maintained at 120 ° C., and the coating film was dried to form a simulated electrode catalyst layer on the transfer sheet.
  • the catalyst solution is not repelled on the coating surface, and the formed electrode catalyst layer is visually observed to show no defects such as cracks. ⁇ ) ”, and other cases were evaluated as“ coatability / impossible ( ⁇ ) ”.
  • a nonporous non-porous PTFE sheet was prepared as a transfer sheet (sample 7 as a comparative example).
  • thermo transfer characteristics A sample on which a simulated electrode catalyst layer was formed was evaluated for thermal transfer characteristics, more specifically, whether stable thermal transfer of the electrode catalyst layer was possible as follows.
  • An adhesive tape (manufactured by Nitto Denko Corporation, No. 360UL, 65 ⁇ m in thickness, 20 mm in width ⁇ 150 mm in length) was prepared as a member for thermally transferring the electrode catalyst layer.
  • the adhesive tape and the sample were laminated so that the adhesive surface of the adhesive tape and the electrode catalyst layer formed on the sample were in contact with each other. Lamination was performed such that the entire electrode catalyst layer was in contact with the adhesive tape.
  • a manual roller having a mass of 2 kg was reciprocated once in the length direction of the laminate, and the adhesive tape and the sample were pressure bonded.
  • the manual roller the one specified in JIS Z0237, item 10.3.1 was used.
  • the laminate was hot-pressed for 30 seconds under a pressurizing condition of a linear pressure of 4.5 kN using a hot press set at room temperature, 120 ° C., 150 ° C. or 180 ° C.
  • a hot press set at room temperature, 120 ° C., 150 ° C. or 180 ° C.
  • the sample was peeled by hand and the state of the electrode catalyst layer transferred to the adhesive tape was visually observed.
  • thermo transfer characteristics / good ( ⁇ ) when the electrode catalyst layer did not show any defects such as deformation, damage, surface loss, etc., it was defined as “thermal transfer characteristics / good ( ⁇ )”, and when defects were partially observed, “thermal transfer characteristics / Depending on the conditions of use of the electrode catalyst layer, “Yes ( ⁇ )” was given, and when a defect was found overall, “thermal transfer characteristics / impossible (x)”.
  • the thermal transfer characteristics of Samples 1 to 4 were good ( ⁇ ) under any thermal transfer conditions of room temperature, 120 ° C., 150 ° C., and 180 ° C.
  • the thermal transfer characteristic of Sample 5 as a comparative example was acceptable ( ⁇ ) under the thermal transfer condition of 150 ° C.
  • the thermal transfer characteristic of Sample 6 as a comparative example was not possible (x) under the thermal transfer conditions of 150 ° C. and 180 ° C.
  • a part of the PTFE porous layer is agglomerated and destroyed at the time of thermal transfer under the high-temperature thermal transfer conditions in which thermal transfer characteristics are enabled or disabled, and adhere to the surface of the transferred electrode catalyst layer. It was.
  • the transfer sheet of the present disclosure can be used, for example, for transferring an electrode catalyst layer provided in an electrochemical element such as a fuel cell.

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Inert Electrodes (AREA)
  • Fuel Cell (AREA)
  • Laminated Bodies (AREA)

Abstract

A transfer sheet according to the present disclosure is for transferring a layer, and has a substrate layer and a pair of fluororesin porous layers which are bonded to the substrate layer and holds the substrate layer therebetween, wherein at least one of the fluororesin porous layers has a cohesive force of 1.8 N/20 mm or more. By means of the transfer sheet according to the present disclosure, it is possible to satisfactorily perform a heat transfer of a layer to be transferred (a transfer layer), even when the heat transfer temperature is high.

Description

層を転写するための転写シート及び電極触媒層付きシートSheet for transferring layer and sheet with electrode catalyst layer
　本発明は、層を転写するための転写シートに関し、より具体的には、燃料電池等の電気化学素子が備える電極触媒層の担持及び転写に使用できる転写シートに関する。また、本発明は、電極触媒層付きシートに関する。 The present invention relates to a transfer sheet for transferring a layer, and more specifically to a transfer sheet that can be used for supporting and transferring an electrode catalyst layer provided in an electrochemical element such as a fuel cell. The present invention also relates to a sheet with an electrode catalyst layer.
　固体高分子型燃料電池（ＰＥＦＣ：Polymer Electrolyte Fuel Cell）では、主要な構成要素として、膜電極接合体(ＭＥＡ)が用いられる。ＭＥＡは、通常、電解質膜と電極触媒層とを備える。より具体的には、燃料極用及び空気極用の一対の電極触媒層が、それぞれ、電解質膜の各主面に積層されている。電極触媒層の表面に更に拡散層が形成されたＭＥＡの構成も採用されている。 In a polymer electrolyte fuel cell (PEFC), a membrane electrode assembly (MEA) is used as a main component. The MEA usually includes an electrolyte membrane and an electrode catalyst layer. More specifically, a pair of electrode catalyst layers for the fuel electrode and the air electrode are respectively laminated on the main surfaces of the electrolyte membrane. An MEA configuration in which a diffusion layer is further formed on the surface of the electrode catalyst layer is also employed.
　電極触媒層を電解質膜に積層する方法の一つに転写法がある。転写法では、電極触媒層を表面に担持したシートを準備し、当該シートを転写シートとして、電極触媒層を電解質膜に熱転写する。特許文献１には、帯状の電解質膜と、電極触媒層を担持した帯状のシートとを積層して積層体とし、加熱した一対の熱転写ロールの間に通した後、シートを剥離して、電極触媒層を電解質膜に連続的に熱転写する方法が開示されている。特許文献２には、基材上に形成された電極触媒層を熱プレスによって高分子電解質膜に接合した後、基材を剥離して、電極触媒層を電解質膜に熱転写する方法が開示されている。 One method of laminating the electrode catalyst layer on the electrolyte membrane is a transfer method. In the transfer method, a sheet carrying the electrode catalyst layer on the surface is prepared, and the electrode catalyst layer is thermally transferred to the electrolyte membrane using the sheet as a transfer sheet. In Patent Document 1, a belt-shaped electrolyte membrane and a belt-shaped sheet carrying an electrode catalyst layer are laminated to form a laminate, and after passing between a pair of heated thermal transfer rolls, the sheet is peeled off, A method is disclosed in which a catalyst layer is continuously thermally transferred to an electrolyte membrane. Patent Document 2 discloses a method in which an electrode catalyst layer formed on a base material is bonded to a polymer electrolyte membrane by hot pressing, and then the base material is peeled off to thermally transfer the electrode catalyst layer to the electrolyte membrane. Yes.
特開２００８－１０３２５１号公報JP 2008-103251 A 特開２０１３－０７３８９２号公報JP2013-073892A
　燃料電池の小型化に伴う電極触媒層の薄層化が進んでいる。薄層化された電極触媒層では、従来にも増して、ＭＥＡの面内方向における均質性の向上が求められる。薄層化された電極触媒層において、電解質膜に転写された状態での均質性が燃料電池の発電特性に与える影響は大きい。また、薄層化された電極触媒層を電解質膜に確実に転写することを目的とした熱転写温度の上昇が想定される。しかし、本発明者らの検討によれば、熱転写温度の上昇に伴って、変形、亀裂、欠落等の欠陥が転写後の電極触媒層に生じやすくなる。 The electrode catalyst layer is becoming thinner with the miniaturization of fuel cells. The thinned electrode catalyst layer is required to improve the homogeneity in the in-plane direction of the MEA, as compared with the prior art. In the thin electrode catalyst layer, the homogeneity in the state transferred to the electrolyte membrane has a great influence on the power generation characteristics of the fuel cell. In addition, an increase in thermal transfer temperature for the purpose of reliably transferring the thinned electrode catalyst layer to the electrolyte membrane is assumed. However, according to the study by the present inventors, defects such as deformation, cracks, and loss tend to occur in the electrode catalyst layer after transfer as the thermal transfer temperature rises.
　本発明は、熱転写温度が高い場合にも、転写される層の熱転写を良好に実施できる転写シートを提供することを目的とする。 An object of the present invention is to provide a transfer sheet that can satisfactorily perform thermal transfer of a transferred layer even when the thermal transfer temperature is high.
　本発明は、
　層を転写するための転写シートであって、
　基材層と、前記基材層に接合された、前記基材層を挟持する一対のフッ素樹脂多孔質層と、を備え、
　少なくとも一方の前記フッ素樹脂多孔質層が、１．８Ｎ／２０ｍｍ以上の凝集力を有する、転写シート、
　を提供する。 The present invention
A transfer sheet for transferring the layer,
A base material layer, and a pair of fluororesin porous layers that are bonded to the base material layer and sandwich the base material layer,
A transfer sheet in which at least one of the fluororesin porous layers has a cohesive force of 1.8 N / 20 mm or more,
I will provide a.
　別の側面から、本発明は、
　上記本発明の転写シートと、電極触媒層とを備え、
　前記電極触媒層が、前記少なくとも一方のフッ素樹脂多孔質層の上に配置されている、電極触媒層付きシート、
　を提供する。 From another aspect, the present invention provides:
The transfer sheet of the present invention, and an electrode catalyst layer,
The electrode catalyst layer is disposed on the at least one fluororesin porous layer, a sheet with an electrode catalyst layer,
I will provide a.
　本発明の転写シートでは、フッ素樹脂多孔質層によって転写層の担持面が構成される。フッ素樹脂多孔質層を構成するフッ素樹脂は、高い離型性を有する。また、多孔質層であるが故に、非多孔質層に比べて、担持面における転写層との接触面積を低減できる。このため、本発明の転写シートでは、熱転写時における転写層の高い離型性が確保される。 In the transfer sheet of the present invention, the support surface of the transfer layer is constituted by the fluororesin porous layer. The fluororesin constituting the fluororesin porous layer has a high releasability. Moreover, since it is a porous layer, the contact area with the transfer layer on the carrying surface can be reduced as compared with the non-porous layer. For this reason, in the transfer sheet of the present invention, high releasability of the transfer layer during thermal transfer is ensured.
　また、本発明の転写シートでは、凝集力が高いフッ素樹脂多孔質層の表面を転写層の担持面とすることができる。凝集力は、厚さ方向の層の破壊強度に相当する。フッ素樹脂多孔質層の凝集力が高いと、熱転写温度が高い場合にも、熱転写時におけるフッ素樹脂多孔質層の凝集破壊（例えば、転写層の離型時における層の内部破壊）が抑制される。これにより、転写層の安定した熱転写が可能となる。 Moreover, in the transfer sheet of the present invention, the surface of the fluororesin porous layer having a high cohesive force can be used as the carrying surface of the transfer layer. The cohesive force corresponds to the breaking strength of the layer in the thickness direction. When the cohesive force of the fluororesin porous layer is high, cohesive failure of the fluororesin porous layer during thermal transfer (for example, internal destruction of the layer during release of the transfer layer) is suppressed even when the thermal transfer temperature is high. . Thereby, stable thermal transfer of the transfer layer becomes possible.
　更に、本発明の転写シートは、一対のフッ素樹脂多孔質層によって基材層が挟持された構造を有している。このため、フッ素樹脂多孔質層と基材層との間の熱膨張係数の相違に起因する熱転写時の転写シートの変形、典型的にはカール、を抑制できる。また、フッ素樹脂多孔質層のみからなる場合に比べて、熱転写時における転写シートの延びが基材層によって抑制される。これらの点も、熱転写温度が高い場合における転写層の安定した熱転写に寄与する。 Furthermore, the transfer sheet of the present invention has a structure in which the base material layer is sandwiched between a pair of fluororesin porous layers. For this reason, the deformation | transformation of the transfer sheet at the time of thermal transfer resulting from the difference in the thermal expansion coefficient between the fluororesin porous layer and the base material layer, typically curl, can be suppressed. In addition, the extension of the transfer sheet at the time of thermal transfer is suppressed by the base material layer as compared with the case where it is composed only of the fluororesin porous layer. These points also contribute to stable thermal transfer of the transfer layer when the thermal transfer temperature is high.
　したがって、本発明の転写シートによれば、熱転写温度が高い場合にも、転写層の熱転写を良好に実施できる。 Therefore, according to the transfer sheet of the present invention, even when the thermal transfer temperature is high, the transfer layer can be favorably thermally transferred.
本発明の転写シートの一例を模式的に示す断面図である。It is sectional drawing which shows an example of the transfer sheet of this invention typically. 転写シートのカール高さを評価する方法を説明するための模式図である。It is a schematic diagram for demonstrating the method to evaluate the curl height of a transfer sheet. 転写シートのカール高さを評価する方法を説明するための模式図である。It is a schematic diagram for demonstrating the method to evaluate the curl height of a transfer sheet. 本発明の電極触媒層付きシートの一例を模式的に示す断面図である。It is sectional drawing which shows typically an example of the sheet | seat with an electrode catalyst layer of this invention. 本発明の転写シートを用いて製造できるＭＥＡの一例を模式的に示す断面図である。It is sectional drawing which shows typically an example of MEA which can be manufactured using the transfer sheet of this invention. 本発明の転写シートを用いてＭＥＡを製造する方法の一例を模式的に示す図である。It is a figure which shows typically an example of the method of manufacturing MEA using the transfer sheet of this invention. フッ素樹脂多孔質層の凝集力を評価する方法を説明するための模式図である。It is a schematic diagram for demonstrating the method to evaluate the cohesion force of a fluororesin porous layer.
　以下、本発明の実施形態について、図面を参照しながら説明する。以下は本発明の一例に関する説明であり、本発明はこの一例が示す範囲に限定されない。 Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following is an explanation of an example of the present invention, and the present invention is not limited to the range shown by this example.
　［転写シート］
　本開示の転写シートの一例を図１に示す。転写シート１０は、基材層１と、基材層１を挟持する一対のフッ素樹脂多孔質層２ａ，２ｂとを備える。転写シート１０は、その上に形成、担持された転写層を他の部材に転写するための転写シートである。転写シート１０において、一方のフッ素樹脂多孔質層２ａは、１．８Ｎ／２０ｍｍ以上の凝集力を有している。転写シート１０では、フッ素樹脂多孔質層２ａにより転写層の担持面を構成できる。より具体的には、フッ素樹脂多孔質層２ａにおける基材層１と接している側とは反対側の主面（露出面）２１を転写層の担持面とすることができる。図１に示すように、他方のフッ素樹脂多孔質層２ｂの主面２２が露出している転写シート１０では、主面２１及び主面２２の双方を転写層の担持面としてもよい。 [Transfer sheet]
An example of the transfer sheet of the present disclosure is shown in FIG. The transfer sheet 10 includes a base material layer 1 and a pair of fluororesin porous layers 2 a and 2 b that sandwich the base material layer 1. The transfer sheet 10 is a transfer sheet for transferring a transfer layer formed and supported thereon to another member. In the transfer sheet 10, one fluororesin porous layer 2a has a cohesive force of 1.8 N / 20 mm or more. In the transfer sheet 10, the support surface of the transfer layer can be constituted by the fluororesin porous layer 2a. More specifically, the main surface (exposed surface) 21 opposite to the side in contact with the base material layer 1 in the fluororesin porous layer 2a can be used as a transfer layer support surface. As shown in FIG. 1, in the transfer sheet 10 in which the main surface 22 of the other fluororesin porous layer 2b is exposed, both the main surface 21 and the main surface 22 may be used as the transfer layer carrying surface.
　フッ素樹脂多孔質層の凝集力は、厚さ方向における当該層の破壊強度に相当する。即ち、凝集力が高いほど、厚さ方向に加わる力に対してフッ素樹脂多孔質層が破壊され難くなる。転写層の離型時にフッ素樹脂多孔質層の内部破壊が進行すると、フッ素樹脂多孔質層の一部が転写層と共に剥離することもある。フッ素樹脂多孔質層２ａの凝集力の下限は、１．９Ｎ／２０ｍｍ以上、更には２．０Ｎ／２０ｍｍ以上であってもよい。フッ素樹脂多孔質層２ａの凝集力の上限は、例えば４．５Ｎ／２０ｍｍ以下であり、４．０Ｎ／２０ｍｍ以下、３．５Ｎ／２０ｍｍ以下、更には３．０Ｎ／２０ｍｍ以下であってもよい。フッ素樹脂多孔質層の凝集力は、１８０°引きはがし試験により評価できる。 The cohesive force of the fluororesin porous layer corresponds to the breaking strength of the layer in the thickness direction. That is, the higher the cohesive force, the harder the fluororesin porous layer is destroyed by the force applied in the thickness direction. When internal destruction of the fluororesin porous layer proceeds during release of the transfer layer, a part of the fluororesin porous layer may be peeled off together with the transfer layer. The lower limit of the cohesive force of the fluororesin porous layer 2a may be 1.9 N / 20 mm or more, and further 2.0 N / 20 mm or more. The upper limit of the cohesive force of the fluororesin porous layer 2a is, for example, 4.5 N / 20 mm or less, and may be 4.0 N / 20 mm or less, 3.5 N / 20 mm or less, or even 3.0 N / 20 mm or less. . The cohesive force of the fluororesin porous layer can be evaluated by a 180 ° peeling test.
　フッ素樹脂多孔質層の凝集力は、例えば、フッ素樹脂多孔質層の平均孔径、厚さ、単位面積あたりの膜重量等の特性により制御できる。また、フッ素樹脂多孔質層の各特性は、フッ素樹脂多孔質層の製造条件、例えば、フッ素樹脂多孔質層を形成するための延伸条件、により制御できる。 The cohesive force of the fluororesin porous layer can be controlled by characteristics such as the average pore diameter, thickness, and membrane weight per unit area of the fluororesin porous layer. Moreover, each characteristic of a fluororesin porous layer can be controlled by the manufacturing conditions of a fluororesin porous layer, for example, the extending conditions for forming a fluororesin porous layer.
　フッ素樹脂多孔質層２ａの厚さは、例えば１００μｍ以下であり、７０μｍ以下、５０μｍ以下、４０μｍ以下、３０μｍ以下、２０μｍ以下、更には１０μｍ以下であってもよい。フッ素樹脂多孔質層２ａの厚さが小さくなるほど、担持面の凹凸の程度が小さくなる傾向にある。担持面の凹凸の程度が小さくなると、熱転写時に当該凹凸が転写層に与える影響を低減できる。フッ素樹脂多孔質層２ａの厚さの下限は、例えば３μｍ以上であり、４μｍ以上、更には５μｍ以上であってもよい。 The thickness of the fluororesin porous layer 2a is, for example, 100 μm or less, and may be 70 μm or less, 50 μm or less, 40 μm or less, 30 μm or less, 20 μm or less, or even 10 μm or less. As the thickness of the fluororesin porous layer 2a decreases, the degree of unevenness on the carrying surface tends to decrease. When the degree of unevenness on the support surface is reduced, the influence of the unevenness on the transfer layer during thermal transfer can be reduced. The lower limit of the thickness of the fluororesin porous layer 2a is, for example, 3 μm or more, 4 μm or more, and further 5 μm or more.
　フッ素樹脂多孔質層の厚さは、転写シートの断面像を画像解析して評価できる。断面像の例は、転写シートの断面に対する光学顕微鏡又は電子顕微鏡による拡大観察像である。拡大観察像の倍率は、例えば５００倍程度とすればよい。画像解析では、場所を変えながら少なくとも１０の測定ポイントにおける厚さを評価する。評価した各測定ポイントにおける厚さの平均値を、フッ素樹脂多孔質層の厚さとすることができる。 The thickness of the fluororesin porous layer can be evaluated by analyzing the cross-sectional image of the transfer sheet. The example of a cross-sectional image is an enlarged observation image by an optical microscope or an electron microscope with respect to the cross section of the transfer sheet. The magnification of the magnified observation image may be about 500 times, for example. In the image analysis, the thickness at at least 10 measurement points is evaluated while changing the location. The average value of the thickness at each evaluated measurement point can be the thickness of the fluororesin porous layer.
　フッ素樹脂多孔質層２ｂの凝集力は、上述したフッ素樹脂多孔質層２ａの凝集力の範囲内にあってもよい。フッ素樹脂多孔質層２ｂの厚さは、上述したフッ素樹脂多孔質層２ａの厚さの範囲内にあってもよい。フッ素樹脂多孔質層２ｂは、１．８Ｎ／２０ｍｍ以上の凝集力及び／又は１００μｍ以下の厚さを有していてもよい。 The cohesive force of the fluororesin porous layer 2b may be within the range of the cohesive force of the fluororesin porous layer 2a described above. The thickness of the fluororesin porous layer 2b may be within the range of the thickness of the fluororesin porous layer 2a described above. The fluororesin porous layer 2b may have a cohesive force of 1.8 N / 20 mm or more and / or a thickness of 100 μm or less.
　転写シート１０が備える一対のフッ素樹脂多孔質層２ａ，２ｂの凝集力及び／又は厚さは、同一であってもよい。この形態は、主面２１を担持面として使用した後、主面２２を担持面として転写シート１０を再利用する場合に適している。また、フッ素樹脂多孔質層２ａ，２ｂの厚さが同一であると、熱転写の熱による転写シート１０の変形、典型的にはカール、をより確実に抑制できる。このため、熱転写温度が高い場合にも、転写シート１０による転写層の熱転写を更に良好に実施できる。転写シート１０が備える一対のフッ素樹脂多孔質層２ａ，２ｂは、同一の構成を有していてもよい。 The cohesive force and / or thickness of the pair of fluororesin porous layers 2a and 2b provided in the transfer sheet 10 may be the same. This configuration is suitable for the case where the transfer sheet 10 is reused with the main surface 22 as the support surface after the main surface 21 is used as the support surface. Further, when the fluororesin porous layers 2a and 2b have the same thickness, deformation of the transfer sheet 10 due to heat of thermal transfer, typically curl, can be more reliably suppressed. For this reason, even when the thermal transfer temperature is high, thermal transfer of the transfer layer by the transfer sheet 10 can be more satisfactorily performed. The pair of fluororesin porous layers 2a and 2b included in the transfer sheet 10 may have the same configuration.
　転写シート１０によって転写される転写層は、例えば、燃料電池等の電気化学素子に使用される電極触媒層である。電極触媒層の例は、ＭＥＡが備える電極触媒層である。電極触媒層には、その前駆層も含まれる。ただし、転写シート１０によって転写される転写層は、電極触媒層に限定されない。 The transfer layer transferred by the transfer sheet 10 is, for example, an electrode catalyst layer used for an electrochemical element such as a fuel cell. The example of an electrode catalyst layer is an electrode catalyst layer with which MEA is provided. The electrode catalyst layer includes a precursor layer thereof. However, the transfer layer transferred by the transfer sheet 10 is not limited to the electrode catalyst layer.
　転写シート１０上の電極触媒層は、通常、触媒電極及び拡散溶媒を含む触媒溶液を、転写シート１０の担持面に塗布して形成される。また、薄層化された電極触媒層の形成には、一般に、低固形分濃度及び／又は低粘度の触媒溶液が使用される。転写シート１０の担持面は多孔質である。このため、低固形分濃度及び／又は低粘度の触媒溶液を使用する場合においても、非多孔質の担持面に比べて触媒溶液が弾かれ難く、触媒溶液の塗工性を向上できる。塗工性が向上すると、例えば、面内方向のより高い均質性を有する電極触媒層の形成が可能になる。したがって、転写シート１０は、電極触媒層の転写シート（電極触媒層用転写シート）、とりわけ、薄層化された電極触媒層の転写シート、として高いメリットを有する。 The electrode catalyst layer on the transfer sheet 10 is usually formed by applying a catalyst solution containing a catalyst electrode and a diffusion solvent to the carrying surface of the transfer sheet 10. In addition, a catalyst solution having a low solid content concentration and / or a low viscosity is generally used to form a thin electrode catalyst layer. The carrying surface of the transfer sheet 10 is porous. For this reason, even when a catalyst solution having a low solid content concentration and / or a low viscosity is used, the catalyst solution is less likely to be repelled than a non-porous support surface, and the coating property of the catalyst solution can be improved. When the coatability is improved, for example, an electrode catalyst layer having higher homogeneity in the in-plane direction can be formed. Therefore, the transfer sheet 10 has high merit as an electrode catalyst layer transfer sheet (electrode catalyst layer transfer sheet), in particular, a thin electrode catalyst layer transfer sheet.
　図１の転写シート１０では、フッ素樹脂多孔質層２ａ，２ｂと基材層１とが融着により接合されている。融着による接合は、均一な厚さの転写シート１０の形成と、転写シート１０の製造コストの削減とに適している。 In the transfer sheet 10 of FIG. 1, the fluororesin porous layers 2a and 2b and the base material layer 1 are joined by fusion bonding. Bonding by fusion is suitable for forming the transfer sheet 10 having a uniform thickness and reducing the manufacturing cost of the transfer sheet 10.
　フッ素樹脂多孔質層２ａ，２ｂと基材層１との融着は、例えば、熱ラミネート、熱プレスにより実施できる。熱ラミネートの一例では、１３０～２９０℃に保持した熱ロールを１０～４０Ｎ／ｍの線圧で押し付けることで、フッ素樹脂多孔質層２ａ，２ｂと基材層１とを融着する。このときのライン速度は、熱ロール径及び加熱温度等により異なるが、例えば３．０～２０．０ｍ／分である。ただし、フッ素樹脂多孔質層２ａ，２ｂと基材層１とを融着する方法は、上記例に限定されない。 The fusion between the fluororesin porous layers 2a and 2b and the base material layer 1 can be performed by, for example, thermal lamination or hot pressing. In an example of a thermal laminate, the fluororesin porous layers 2a and 2b and the base material layer 1 are fused by pressing a hot roll maintained at 130 to 290 ° C. with a linear pressure of 10 to 40 N / m. The line speed at this time varies depending on the hot roll diameter, the heating temperature, and the like, but is, for example, 3.0 to 20.0 m / min. However, the method of fusing the fluororesin porous layers 2a and 2b and the base material layer 1 is not limited to the above example.
　また、フッ素樹脂多孔質層２ａ，２ｂと基材層１との接合の形態は、融着に限定されない。フッ素樹脂多孔質層２ａ，２ｂと基材層１とは、例えば、接着剤又は粘着剤により接合されていてもよい。 Further, the form of bonding between the fluororesin porous layers 2a and 2b and the base material layer 1 is not limited to fusion. The fluororesin porous layers 2a and 2b and the base material layer 1 may be joined by, for example, an adhesive or a pressure-sensitive adhesive.
　転写シート１０の厚さは、例えば１５μｍ～４００μｍであり、５０μｍ～３００μｍであってもよい。 The thickness of the transfer sheet 10 is, for example, 15 μm to 400 μm, and may be 50 μm to 300 μm.
　基材層１は、転写シート１０におけるフッ素樹脂多孔質層２ａ，２ｂの補強層としての役割も担っている。基材層１を備えることにより、例えば、転写シート１０の強度及び／又は取扱性が向上する。取扱性には、搬送性が含まれる。また、基材層１を備えることにより、例えば、ロールから供給した帯状の転写シート１０を用いたロールｔｏロールによる転写層の転写を、より安定かつ確実に実施できる。 The base material layer 1 also serves as a reinforcing layer for the fluororesin porous layers 2 a and 2 b in the transfer sheet 10. By providing the base material layer 1, for example, the strength and / or handleability of the transfer sheet 10 is improved. Handleability includes transportability. Moreover, by providing the base material layer 1, for example, transfer of the transfer layer by roll-to-roll using the belt-shaped transfer sheet 10 supplied from the roll can be more stably and reliably performed.
　基材層１は、例えば、樹脂層、金属層、紙層、無機物層である。転写層が電極触媒層である場合、電極触媒層への金属の混入を防ぐ観点からは、樹脂層、特に熱可塑性樹脂層、である基材層１が好ましい。ただし、樹脂層からは、フッ素樹脂多孔質層が除かれる。 The base material layer 1 is, for example, a resin layer, a metal layer, a paper layer, or an inorganic layer. When the transfer layer is an electrode catalyst layer, the base material layer 1 which is a resin layer, particularly a thermoplastic resin layer, is preferable from the viewpoint of preventing the metal from being mixed into the electrode catalyst layer. However, the fluororesin porous layer is excluded from the resin layer.
　基材層１を構成する金属は、例えば、アルミニウム、ステンレスである。 The metal constituting the base material layer 1 is, for example, aluminum or stainless steel.
　基材層１を構成する熱可塑性樹脂の融点は、好ましくは２８０℃以下である。２８０℃以下の融点を有する熱可塑性樹脂から構成される基材層１は、フッ素樹脂多孔質層２ａ，２ｂとの融着性が良好である。熱可塑性樹脂の例は、ポリエステル、ポリアセタール、ポリエチレン、超高分子量ポリエチレン及びポリプロピレンから選ばれる少なくとも１種である。ポリエステルの例は、ポリエチレンテレフタレート（ＰＥＴ）及びポリブチレンテレフタレートである。フッ素樹脂多孔質層２ａ，２ｂとの融着時に変質し難く、耐熱性及び耐薬品性に優れることから、ポリアセタール及びＰＥＴが好ましく、ＰＥＴがより好ましい。ＰＥＴは、軟化温度が低いグレードが好ましく、とりわけ、２３３℃よりも低い温度で軟化を始めるグレードが好ましい。 The melting point of the thermoplastic resin constituting the base material layer 1 is preferably 280 ° C. or lower. The base material layer 1 composed of a thermoplastic resin having a melting point of 280 ° C. or less has good fusion properties with the fluororesin porous layers 2a and 2b. Examples of the thermoplastic resin are at least one selected from polyester, polyacetal, polyethylene, ultrahigh molecular weight polyethylene, and polypropylene. Examples of polyesters are polyethylene terephthalate (PET) and polybutylene terephthalate. Polyacetal and PET are preferable, and PET is more preferable because it hardly changes in quality when fused to the fluororesin porous layers 2a and 2b and is excellent in heat resistance and chemical resistance. PET is preferably a grade having a low softening temperature, and in particular, a grade that starts softening at a temperature lower than 233 ° C. is preferable.
　基材層１は、典型的には無孔層である。無孔の基材層１は、フッ素樹脂多孔質層２ａに面する主面１１の表面粗さを小さくすることに適している。主面１１の表面粗さ１１が小さいと、フッ素樹脂多孔質層２ａの主面２１（担持面）における凹凸の程度を更に低減できる。また、この場合、転写層の安定した保持が可能となる。ただし、基材層１は無孔層に限定されず、例えば、織布、不織布、ネット、延伸多孔膜、微粒子融着多孔膜等により構成される多孔層であってもよい。 The base material layer 1 is typically a non-porous layer. The non-porous base material layer 1 is suitable for reducing the surface roughness of the main surface 11 facing the fluororesin porous layer 2a. When the surface roughness 11 of the main surface 11 is small, the degree of unevenness on the main surface 21 (supporting surface) of the fluororesin porous layer 2a can be further reduced. In this case, the transfer layer can be stably held. However, the base material layer 1 is not limited to the non-porous layer, and may be a porous layer constituted by, for example, a woven fabric, a nonwoven fabric, a net, a stretched porous film, a fine particle fusion porous film, or the like.
　基材層１の厚さは、例えば１２．５μｍ～２００μｍであり、２５～１７５μｍであってもよい。基材層１の厚さが過度に小さくなると、基材層１による補強効果が薄れ、転写シート１０の強度及び／又は取扱性が低下することがある。基材層１の厚さが過度に大きくなると、例えば、転写シート１０をロールとした場合に、ロールの重量が過大となることがある。 The thickness of the base material layer 1 is, for example, 12.5 μm to 200 μm, and may be 25 to 175 μm. When the thickness of the base material layer 1 becomes excessively small, the reinforcing effect by the base material layer 1 is reduced, and the strength and / or handleability of the transfer sheet 10 may be reduced. When the thickness of the base material layer 1 is excessively large, for example, when the transfer sheet 10 is a roll, the weight of the roll may be excessive.
　フッ素樹脂多孔質層２ａ，２ｂを構成するフッ素樹脂の例は、ポリテトラフルオロエチレン（ＰＴＦＥ）、テトラフルオロエチレン－パーフルオロアルキルビニルエーテル共重合体（ＰＦＡ）及びテトラフルオロエチレン－ヘキサフルオロプロピレン共重合体（ＦＥＰ）である。好ましいフッ素樹脂は、ＰＴＦＥである。フッ素樹脂多孔質層２ａは、ＰＴＦＥ多孔質層であることが好ましい。フッ素樹脂多孔質層２ａ，２ｂの双方が、同一のフッ素樹脂から構成されていてもよい。フッ素樹脂多孔質層２ａ，２ｂは、フッ素樹脂以外の成分を含んでいなくてもよく、フッ素樹脂以外の成分を実質的に含まなくてもよい。本明細書において「実質的に含まない」とは、含有率が０．１重量％未満、好ましくは０．０１重量％未満であることを意味する。 Examples of the fluororesin constituting the fluororesin porous layers 2a and 2b are polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), and tetrafluoroethylene-hexafluoropropylene copolymer. (FEP). A preferred fluororesin is PTFE. The fluororesin porous layer 2a is preferably a PTFE porous layer. Both the fluororesin porous layers 2a and 2b may be composed of the same fluororesin. The fluororesin porous layers 2a and 2b may not contain components other than the fluororesin, and may not substantially contain components other than the fluororesin. In this specification, “substantially free” means that the content is less than 0.1 wt%, preferably less than 0.01 wt%.
　フッ素樹脂多孔質層２ａの平均孔径は、例えば０．１～２０μｍであり、０．２～１５μｍ、０．２～１０μｍ、更には１．５～７．０μｍであってもよい。フッ素樹脂多孔質層２ａの平均孔径が上記範囲にあると、転写層の熱転写をより良好に実施できる。平均孔径が過度に大きくなると、例えば転写層が電極触媒層である場合に、電極触媒層に含まれるカーボン粒子や触媒粒子が熱転写時にフッ素樹脂多孔質層２ａの孔内に取り込まれ、熱転写された転写層の表面が荒れることがある。フッ素樹脂多孔質層２ａ，２ｂの双方の平均孔径が上記範囲にあってもよい。フッ素樹脂多孔質層２ａ，２ｂの双方の平均孔径は同一であってもよい。 The average pore diameter of the fluororesin porous layer 2a is, for example, 0.1 to 20 μm, and may be 0.2 to 15 μm, 0.2 to 10 μm, or even 1.5 to 7.0 μm. When the average pore diameter of the fluororesin porous layer 2a is in the above range, thermal transfer of the transfer layer can be carried out more favorably. When the average pore diameter becomes excessively large, for example, when the transfer layer is an electrode catalyst layer, carbon particles and catalyst particles contained in the electrode catalyst layer are taken into the pores of the fluororesin porous layer 2a during thermal transfer and thermally transferred. The surface of the transfer layer may become rough. The average pore diameter of both of the fluororesin porous layers 2a and 2b may be in the above range. The average pore diameters of both the fluororesin porous layers 2a and 2b may be the same.
　フッ素樹脂多孔質層２ａの主面２１における水との接触角は、例えば１００度以上であり、１２０度以上、更には１３０度以上であってもよい。水との高い接触角を有する主面は、転写層との離型性に特に優れている。フッ素樹脂多孔質層２ｂの主面２２における水との接触角が上記範囲にあってもよい。本明細書において、水との接触角は、日本工業規格（以下、「ＪＩＳ」と記載する）Ｒ３２５７に規定する静滴法により評価した値とする。なお、ＪＩＳ　Ｒ３２５７は基板ガラス表面の接触角を評価する方法に関する規格である。しかし、この規格で定められた試験条件により、転写シート１０の主面における水との接触角を評価可能である。 The contact angle with water on the main surface 21 of the fluororesin porous layer 2a is, for example, 100 degrees or more, 120 degrees or more, and 130 degrees or more. The main surface having a high contact angle with water is particularly excellent in releasability from the transfer layer. The contact angle with water on the main surface 22 of the fluororesin porous layer 2b may be in the above range. In this specification, the contact angle with water is a value evaluated by a sessile drop method defined in Japanese Industrial Standard (hereinafter referred to as “JIS”) R3257. JIS R3257 is a standard relating to a method for evaluating the contact angle of the substrate glass surface. However, the contact angle with water on the main surface of the transfer sheet 10 can be evaluated according to the test conditions defined in this standard.
　転写シート１０を１２０℃の雰囲気に５分間静置させた時の端部のカール高さは、例えば１０ｍｍ以下であり、好ましくは７ｍｍ以下、より好ましくは５ｍｍ以下である。端部のカール高さの評価方法を、図２及び図３を参照しながら説明する。なお、図３の（ａ）及び（ｂ）には、それぞれ、図２の（ａ）及び（ｂ）に示す試験片３１及び平面３２を試験片３１の幅方向に切断した断面を示す。図２の紙面の左右方向が、試験片３１の幅方向である。「幅」は、例えば、シートのＴＤ方向であり、帯状のシートである場合にはその幅方向である。「長さ」は、例えば、シートのＭＤ方向であり、帯状のシートである場合にはその長手方向である。 The curl height at the end when the transfer sheet 10 is allowed to stand in an atmosphere of 120 ° C. for 5 minutes is, for example, 10 mm or less, preferably 7 mm or less, more preferably 5 mm or less. An evaluation method of the curl height at the end will be described with reference to FIGS. 3A and 3B show cross sections obtained by cutting the test piece 31 and the plane 32 shown in FIGS. 2A and 2B in the width direction of the test piece 31, respectively. The left-right direction of the paper surface of FIG. “Width” is, for example, the TD direction of the sheet, and in the case of a belt-like sheet, the width direction. “Length” is, for example, the MD direction of the sheet, and in the case of a belt-like sheet, it is the longitudinal direction thereof.
　最初に、評価対象物である転写シートを４９０ｍｍ幅×５００ｍｍ長さに切出して試験片３１を得る。次に、１２０℃に保持した乾燥機に試験片３１を収容して５分間静置する。その際、カール高さの評価に影響を及ぼすような変形を１２０℃で生じない平面３２上に試験片３１を静置する（図２及び図３の（ａ））。平面３２は、例えば、金属板の表面である。５分間の静置後、平面３２ごと試験片３１を乾燥機から取り出して室温まで冷却する。冷却後、試験片３１における幅方向の双方の端辺（左右の端部）３３ａ，３３ｂの各々について、１２０℃５分間の静置による平面３２からの浮き上がり量（高さｈ１及びｈ２の最大値）を測定する（図２及び図３の（ｂ））。その平均値を、転写シート１０における端部のカール高さとすることができる。 First, a test sheet 31 is obtained by cutting out a transfer sheet, which is an evaluation object, into a width of 490 mm and a length of 500 mm. Next, the test piece 31 is accommodated in a dryer maintained at 120 ° C. and allowed to stand for 5 minutes. At that time, the test piece 31 is allowed to stand on a flat surface 32 that does not cause deformation at 120 ° C. that affects the evaluation of the curl height (FIG. 2 and FIG. 3A). The plane 32 is, for example, the surface of a metal plate. After standing for 5 minutes, the test piece 31 together with the plane 32 is taken out of the dryer and cooled to room temperature. After cooling, the amount of lifting from the plane 32 by standing at 120 ° C. for 5 minutes (maximum values of the heights h1 and h2) for both of the side edges (left and right ends) 33a and 33b in the width direction of the test piece 31 ) Is measured (FIG. 2 and FIG. 3B). The average value can be the curl height at the end of the transfer sheet 10.
　評価対象物である転写シートのサイズが上記試験片３１のサイズ（４９０ｍｍ幅×５００ｍｍ長さ）を満たさない場合には、より小さなサイズで切り出した転写シートを試験片として、上記方法により端部のカール高さを求めることができる。ただし、試験片のサイズが小さくなると、同一の転写シートであっても実際に測定されるカール高さは小さくなる。このため、測定に使用した試験片のサイズに応じた係数を測定値に乗じて、４９０ｍｍ幅×５００ｍｍ長さの試験片を測定に使用した場合の値に換算する。この換算値を、転写シートにおける端部のカール高さとすることができる。換算に使用する係数は、４９０ｍｍ幅×５００ｍｍ長さの試験片を入手可能な転写シートに対して試験片のサイズを変更しながら上記方法による測定を実施し、４９０ｍｍ幅×５００ｍｍ長さの試験片としたときの測定値と、より小さなサイズの試験片としたときの測定値とから算出可能である。例えば、３００ｍｍ幅×３００ｍｍ長さの試験片を用いた場合、４９０ｍｍ幅×５００ｍｍ長さの試験片を用いた場合に比べて、通常、測定値は３％小さくなる。このため、係数１．０３（＝１／（１－０．０３））を測定値に乗じた換算値を、転写シートにおける端部のカール高さとすることができる。また、５０ｍｍ幅×１００ｍｍ長さの試験片を用いた場合、４９０ｍｍ幅×５００ｍｍ長さの試験片を用いた場合に比べて、通常、測定値は１０％小さくなる。このため、係数１．１１（＝１／（１－０．１０））を測定値に乗じた換算値を、転写シートにおける端部のカール高さとすることができる。 When the size of the transfer sheet, which is an evaluation object, does not satisfy the size of the test piece 31 (490 mm width × 500 mm length), the transfer sheet cut out with a smaller size is used as a test piece, and the end of the transfer sheet is measured by the above method. The curl height can be obtained. However, when the size of the test piece is reduced, the actually measured curl height is reduced even with the same transfer sheet. For this reason, the coefficient according to the size of the test piece used for the measurement is multiplied by the measurement value, and converted to a value when a test piece having a width of 490 mm × 500 mm is used for the measurement. This converted value can be the curl height at the end of the transfer sheet. The coefficient used for the conversion was measured by the above method while changing the size of the test piece on a transfer sheet for which a test piece of 490 mm width × 500 mm length was available, and the test piece of 490 mm width × 500 mm length It is possible to calculate from the measured value obtained when the test piece is taken and the measured value obtained when the test piece is smaller in size. For example, when a test piece of 300 mm width × 300 mm length is used, the measured value is usually 3% smaller than when a test piece of 490 mm width × 500 mm length is used. Therefore, a conversion value obtained by multiplying the measured value by a coefficient of 1.03 (= 1 / (1−0.03)) can be used as the curl height of the end portion of the transfer sheet. In addition, when a test piece having a width of 50 mm × 100 mm is used, the measured value is usually 10% smaller than when a test piece having a width of 490 mm × 500 mm is used. Therefore, a conversion value obtained by multiplying the measured value by the coefficient 1.11 (= 1 / (1-0.10)) can be used as the curl height of the end portion of the transfer sheet.
　［電極触媒層付きシート］
　本開示の電極触媒層付きシートの一例を図４に示す。図４に示す電極触媒層付きシート１５は、転写シート１０と、転写シート１０におけるフッ素樹脂多孔質層２ａの主面２１上に配置された転写層３と、を備える積層シートである。図４の形態において、転写層３は電極触媒層である。電極触媒層付きシート１５は、フッ素樹脂多孔質層２ｂ、基材層１、フッ素樹脂多孔質層２ａ及び転写層３が、この順に積層されて構成されている。 [Sheet with electrode catalyst layer]
An example of the sheet with an electrode catalyst layer of the present disclosure is shown in FIG. The sheet 15 with an electrode catalyst layer shown in FIG. 4 is a laminated sheet including the transfer sheet 10 and the transfer layer 3 disposed on the main surface 21 of the fluororesin porous layer 2a in the transfer sheet 10. In the form of FIG. 4, the transfer layer 3 is an electrode catalyst layer. The sheet 15 with an electrode catalyst layer is configured by laminating a fluororesin porous layer 2b, a base material layer 1, a fluororesin porous layer 2a, and a transfer layer 3 in this order.
　電極触媒層付きシート１５が備える転写シート１０は、好ましい形態を含め、上述の説明のとおりである。 The transfer sheet 10 provided in the electrode catalyst layer-attached sheet 15 is as described above, including preferred forms.
　電極触媒層付きシート１５によれば、電解質膜に転写層３を熱転写してＭＥＡを形成できる。図５に示すように、電解質膜５上に熱転写された転写層３は、ＭＥＡ２０の電極触媒層６となる。電極触媒層である転写層３は、好ましい形態を含め、電極触媒層６に関する後述の説明のとおりである。 According to the sheet 15 with the electrode catalyst layer, the transfer layer 3 can be thermally transferred to the electrolyte membrane to form the MEA. As shown in FIG. 5, the transfer layer 3 thermally transferred onto the electrolyte membrane 5 becomes the electrode catalyst layer 6 of the MEA 20. The transfer layer 3, which is an electrode catalyst layer, includes a preferred form and is as described below with respect to the electrode catalyst layer 6.
　［ＭＥＡ］
　転写シート１０又は電極触媒層付きシート１５を使用して製造できる製品の一例は、ＰＥＦＣ等の電気化学素子に用いるＭＥＡである。ただし、転写シート１０又は電極触媒層付きシート１５を使用して製造する製品は、ＭＥＡに限定されない。 [MEA]
An example of a product that can be manufactured using the transfer sheet 10 or the electrode catalyst layer-attached sheet 15 is MEA used for an electrochemical element such as PEFC. However, the product manufactured using the transfer sheet 10 or the electrode catalyst layer-attached sheet 15 is not limited to the MEA.
　図５のＭＥＡ２０は、高分子電解質から構成される電解質膜（高分子電解質膜）５と、電解質膜５を挟持する一対の電極触媒層６とを備える。電極触媒層６は、例えば、直径１μｍ以下の細孔を有する多孔質の薄膜である。電極触媒層６は、主として、触媒物質担持粒子（触媒粒子）と高分子電解質とを含有する。電解質膜５を構成する高分子電解質及び電極触媒層６に含まれる高分子電解質には、フッ素系高分子電解質、炭化水素系高分子電解質等の公知の高分子電解質を用いることができる。 5 includes an electrolyte membrane (polymer electrolyte membrane) 5 made of a polymer electrolyte and a pair of electrode catalyst layers 6 that sandwich the electrolyte membrane 5. The electrode catalyst layer 6 is, for example, a porous thin film having pores having a diameter of 1 μm or less. The electrode catalyst layer 6 mainly contains catalyst material-supporting particles (catalyst particles) and a polymer electrolyte. As the polymer electrolyte constituting the electrolyte membrane 5 and the polymer electrolyte contained in the electrode catalyst layer 6, known polymer electrolytes such as fluorine polymer electrolytes and hydrocarbon polymer electrolytes can be used.
　転写シート１０を使用したＭＥＡの製造方法は、例えば、電極触媒層積層工程、電解質膜積層工程、加熱圧着工程及び剥離工程を含む。電極触媒層積層工程は、熱転写後に電極触媒層となる転写層３を転写シート１０上に形成する工程である。電解質膜積層工程は、転写層３と電解質膜５とが接触するように、転写シート１０と電解質膜５とを積層する工程である。加熱圧着工程は、転写層３と電解質膜５とを加熱圧着する工程である。剥離工程は、転写シート１０を剥離して、電極触媒層６として転写層３を電解質膜５上に残す工程である。電解質膜積層工程、加熱圧着工程及び剥離工程は、転写層３の転写工程を構成する。 The manufacturing method of MEA using the transfer sheet 10 includes, for example, an electrode catalyst layer laminating step, an electrolyte membrane laminating step, a thermocompression bonding step, and a peeling step. The electrode catalyst layer laminating step is a step of forming on the transfer sheet 10 a transfer layer 3 that becomes an electrode catalyst layer after thermal transfer. The electrolyte membrane laminating step is a step of laminating the transfer sheet 10 and the electrolyte membrane 5 so that the transfer layer 3 and the electrolyte membrane 5 are in contact with each other. The thermocompression bonding process is a process in which the transfer layer 3 and the electrolyte membrane 5 are thermocompression bonded. The peeling process is a process of peeling the transfer sheet 10 and leaving the transfer layer 3 on the electrolyte membrane 5 as the electrode catalyst layer 6. The electrolyte membrane lamination step, the thermocompression bonding step, and the peeling step constitute a transfer step for the transfer layer 3.
　電極触媒層積層工程は、例えば、以下のように実施できる。最初に、触媒粒子と高分子電解質とを分散溶媒に分散させた触媒溶液（電極触媒層ペースト）を転写シート１０に塗布して塗布膜を形成する。次に、３０～１８０℃程度の温度で全体を加熱して塗布膜を乾燥させ、転写シート１０と電極触媒層である転写層３との積層シート（電極触媒層付きシート１５）を得る。触媒溶液の塗布には、ドクターブレード法、スクリーン印刷法、ロールコーティング法、スプレー法等の公知の方法を採用できる。 The electrode catalyst layer stacking step can be performed, for example, as follows. First, a catalyst solution (electrode catalyst layer paste) in which catalyst particles and a polymer electrolyte are dispersed in a dispersion solvent is applied to the transfer sheet 10 to form a coating film. Next, the whole is heated at a temperature of about 30 to 180 ° C. to dry the coating film, and a laminated sheet (sheet 15 with the electrode catalyst layer) of the transfer sheet 10 and the transfer layer 3 as the electrode catalyst layer is obtained. For applying the catalyst solution, a known method such as a doctor blade method, a screen printing method, a roll coating method, or a spray method can be employed.
　加熱圧着工程は、例えば、電解質膜５と転写層３とが接した状態にある積層体を熱プレスしたり、一対の熱ロールに通したりして実施できる。加熱圧着の温度は、電解質膜５の種類にもよるが、例えば８０～１５０℃である。電解質膜５の双方の表面に対して転写層３を同時に加熱圧着してもよい。 The thermocompression bonding step can be performed by, for example, hot pressing the laminated body in a state where the electrolyte membrane 5 and the transfer layer 3 are in contact with each other or passing them through a pair of hot rolls. The thermocompression bonding temperature is, for example, 80 to 150 ° C. although it depends on the type of the electrolyte membrane 5. The transfer layer 3 may be thermocompression bonded to both surfaces of the electrolyte membrane 5 at the same time.
　剥離工程は、例えば、転写シート１０を巻き取るロールを用いて、電解質膜５と転写層３との加熱圧着体から転写シート１０を連続的に剥離して実施できる。剥離した転写シート１０は、再利用してもよい。 The peeling step can be performed by, for example, continuously peeling the transfer sheet 10 from the thermocompression bonding body of the electrolyte membrane 5 and the transfer layer 3 using a roll for winding the transfer sheet 10. The peeled transfer sheet 10 may be reused.
　加熱圧着工程及び剥離工程を一連の工程として実施する装置の一例を図６に示す。繰出しロール４１から繰り出した電極触媒層付きシート１５の転写層３を電解質膜５と接触させた後、一対の加熱ロール４３の間を通過させることで、両者を加熱圧着する。その後、転写シート１０のみを剥離し、回収ロール４２に巻き取ることで、電解質膜５と電極触媒層６とが接合された積層体７を連続的に製造できる。 FIG. 6 shows an example of an apparatus that performs the thermocompression bonding process and the peeling process as a series of processes. After the transfer layer 3 of the sheet 15 with the electrode catalyst layer fed from the feed roll 41 is brought into contact with the electrolyte membrane 5, both are thermocompression bonded by passing between the pair of heating rolls 43. Thereafter, only the transfer sheet 10 is peeled off and wound around the collection roll 42, whereby the laminate 7 in which the electrolyte membrane 5 and the electrode catalyst layer 6 are joined can be continuously produced.
　触媒粒子に用いられる触媒物質の例は、白金、パラジウム、ルテニウム、イリジウム、ロジウム、オスミウム等の白金族元素；鉄、鉛、銅、クロム、コバルト、ニッケル、マンガン、バナジウム、モリブデン、ガリウム、アルミニウム等の金属；これらの合金；並びに、これらの金属の酸化物及び複酸化物である。触媒粒子の粒径は、大きすぎると触媒の活性が低下し、小さすぎると触媒の安定性が低下することから、０．５～２０ｎｍが好ましく、１～５ｎｍがより好ましい。白金、金、パラジウム、ロジウム、ルテニウム及びイリジウムから選ばれる１種又は２種以上の金属から構成される触媒粒子は、電極反応性に優れる。このため、当該触媒粒子の使用によって、効率よい安定した電極反応が可能となる。 Examples of catalyst materials used for the catalyst particles include platinum group elements such as platinum, palladium, ruthenium, iridium, rhodium, osmium; iron, lead, copper, chromium, cobalt, nickel, manganese, vanadium, molybdenum, gallium, aluminum, etc. Metals; alloys thereof; and oxides and double oxides of these metals. If the particle size of the catalyst particles is too large, the activity of the catalyst is lowered, and if it is too small, the stability of the catalyst is lowered. Therefore, the particle size is preferably 0.5 to 20 nm, more preferably 1 to 5 nm. The catalyst particles composed of one or more metals selected from platinum, gold, palladium, rhodium, ruthenium and iridium are excellent in electrode reactivity. For this reason, the use of the catalyst particles enables an efficient and stable electrode reaction.
　触媒物質を担持する粒子には、カーボン粒子が適している。カーボン粒子は、微粒子状であって導電性を有し、かつ触媒におかされないものであれば限定されない。カーボン粒子の例は、カーボンブラック、グラファイト、黒鉛、活性炭、カーボンファイバー、カーボンナノチューブ及びフラーレンである。カーボン粒子の粒径は、小さすぎると電子伝導パスが形成され難くなり、大きすぎると電極触媒層のガス拡散性が低下したり、触媒の利用率が低下したりすることから、１０～１０００ｎｍが好ましく、１０～１００ｎｍがより好ましい。 Carbon particles are suitable for the particles carrying the catalyst substance. The carbon particles are not limited as long as they are in the form of fine particles, have conductivity, and are not exposed to the catalyst. Examples of carbon particles are carbon black, graphite, graphite, activated carbon, carbon fiber, carbon nanotube, and fullerene. If the particle size of the carbon particles is too small, it becomes difficult to form an electron conduction path. If the particle size is too large, the gas diffusibility of the electrode catalyst layer is reduced or the utilization factor of the catalyst is reduced. Preferably, 10 to 100 nm is more preferable.
　高分子電解質には、カチオン伝導性及びアニオン伝導性の相違によらず、公知の材料を使用できる。カチオン伝導性は、例えば、プロトン伝導性である。プロトン伝導性を有する高分子電解質には、公知のフッ素系高分子電解質、炭化水素系高分子電解質を使用できる。フッ素系高分子電解質の例は、デュポン社製ナフィオン（登録商標）である。炭化水素系高分子電解質の例は、スルホン化ポリエーテルケトン、スルホン化ポリエーテルスルホン、スルホン化ポリエーテルエーテルスルホン、スルホン化ポリスルフィド、スルホン化ポリフェニレンである。電解質膜と電極触媒層との密着性を考慮すると、電解質膜を構成する高分子電解質と、電極触媒層に含まれる高分子電解質とは同一であることが好ましい。 A known material can be used for the polymer electrolyte regardless of the difference in cation conductivity and anion conductivity. The cation conductivity is, for example, proton conductivity. As the polymer electrolyte having proton conductivity, a known fluorine-based polymer electrolyte or hydrocarbon-based polymer electrolyte can be used. An example of the fluorine-based polymer electrolyte is Nafion (registered trademark) manufactured by DuPont. Examples of the hydrocarbon-based polymer electrolyte are sulfonated polyether ketone, sulfonated polyethersulfone, sulfonated polyetherethersulfone, sulfonated polysulfide, and sulfonated polyphenylene. Considering the adhesion between the electrolyte membrane and the electrode catalyst layer, the polymer electrolyte constituting the electrolyte membrane and the polymer electrolyte contained in the electrode catalyst layer are preferably the same.
　触媒溶液に用いられる分散溶媒は、触媒粒子を侵食することなく、かつ流動性の高い状態で高分子電解質を溶解又は微細ゲルとして分散できるものであれば限定されない。分散溶媒の例は、メタノール、エタノール、１－プロパノ―ル、２－プロパノ―ル、１－ブタノ－ル、２－ブタノ－ル、イソブチルアルコール、ｔｅｒｔ－ブチルアルコール、ペンタノ－ル等のアルコール；アセトン、メチルエチルケトン、ペンタノン、メチルイソブチルケトン、へプタノン、シクロヘキサノン、メチルシクロヘキサノン、アセトニルアセトン、ジイソブチルケトン等のケトン系溶媒；テトラヒドロフラン、ジオキサン、ジエチレングリコールジメチルエーテル、アニソール、メトキシトルエン、ジブチルエーテル等のエーテル系溶媒；ジメチルホルムアミド、ジメチルアセトアミド、Ｎ－メチルピロリドン、エチレングリコール、ジエチレングリコール、ジアセトンアルコール、１－メトキシ－２－プロパノールである。分散溶媒には、揮発性の有機溶媒が含まれていることが好ましく、極性溶媒が含まれていることが好ましい。分散溶媒は、２種以上の上記溶媒の混合物であってもよい。 The dispersion solvent used for the catalyst solution is not limited as long as the polymer electrolyte can be dissolved or dispersed as a fine gel in a highly fluid state without eroding the catalyst particles. Examples of the dispersion solvent include alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butyl alcohol, and pentaanol; acetone Ketone solvents such as methyl ethyl ketone, pentanone, methyl isobutyl ketone, heptanone, cyclohexanone, methyl cyclohexanone, acetonyl acetone, diisobutyl ketone; ether solvents such as tetrahydrofuran, dioxane, diethylene glycol dimethyl ether, anisole, methoxy toluene, dibutyl ether; Formamide, dimethylacetamide, N-methylpyrrolidone, ethylene glycol, diethylene glycol, diacetone alcohol, 1-methoxy-2-propanol. The dispersion solvent preferably contains a volatile organic solvent, and preferably contains a polar solvent. The dispersion solvent may be a mixture of two or more of the above solvents.
　触媒粒子の良好な分散のために、触媒溶液は分散剤を含んでいてもよい。分散剤の例は、アニオン性界面活性剤、カチオン性界面活性剤、両性界面活性剤、非イオン性界面活性剤である。なかでも、アルキルベンゼンスルホン酸、油溶性アルキルベンゼンスルホン酸、α－オレフィンスルホン酸、アルキルベンゼンスルホン酸ナトリウム、油溶性アルキルベンゼンスルホン酸塩、α－オレフィンスルホン酸塩といったスルホン酸型の界面活性剤を、分散剤として好ましく使用できる。 For the good dispersion of the catalyst particles, the catalyst solution may contain a dispersant. Examples of the dispersant are an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant. Among them, sulfonic acid type surfactants such as alkylbenzene sulfonic acid, oil-soluble alkyl benzene sulfonic acid, α-olefin sulfonic acid, sodium alkyl benzene sulfonate, oil-soluble alkyl benzene sulfonate, α-olefin sulfonate are used as dispersants. It can be preferably used.
　以下、実施例により本発明をより詳細に説明する。本発明は、以下の実施例に限定されない。 Hereinafter, the present invention will be described in more detail with reference to examples. The present invention is not limited to the following examples.
　（サンプル１）
　ＰＴＦＥ微粉末（ダイキン工業株式会社製、ポリフロンＦ－１０４）１００重量部と、液状潤滑剤（ｎ－ドデカン、株式会社ジャパンエナジー製）２０重量部とを均一に混合し、シリンダーにて圧縮した後にラム押出成形して、シート状のＰＴＦＥ成形体を形成した。次に、形成したＰＴＦＥ成形体を一対の圧延ロールに通して、厚さ０．２ｍｍに圧延した。次に、圧延したＰＴＦＥ成形体を１５０℃に加熱して液状潤滑剤を除去した後、延伸温度３７０℃及び延伸倍率２０倍の延伸条件でＭＤ方向に延伸し、続いて、延伸温度１８０℃及び延伸倍率５倍の延伸条件でＴＤ方向に延伸して、ＰＴＦＥ多孔質層（厚さ４５μｍ、平均孔径３．０μｍ、単位面積あたりの膜重量０．００９７５ｇ／ｍ2）を得た。なお、単層であるＰＴＦＥ多孔質層の厚さは、ダイヤルゲージにより評価した。具体的には、場所を変えながら少なくとも１０の測定ポイントにおける厚さを評価し、評価した各測定ポイントにおける厚さの平均値をＰＴＦＥ多孔質層の厚さとした。ＰＴＦＥ多孔質層の平均孔径は、米国試験材料協会（ＡＳＴＭ）Ｆ３１６－８６に定められた方法に準拠した自動測定が可能である市販の評価装置（Ｐｏｒｏｕｓ　Ｍａｔｅｒｉａｌｓ，Ｉｎｃ製Ｐｅｒｍ－Ｐｏｒｏｍｅｔｅｒ）により評価した。ＰＴＦＥ多孔質層における単位面積あたりの膜重量は、ＰＴＦＥ多孔質層の重量を当該層の面積で除して求めた。測定精度を確保するために、単位面積あたりの膜重量を評価するＰＴＦＥ多孔質層の面積は５ｍ2以上とした。 (Sample 1)
After 100 parts by weight of PTFE fine powder (Daikin Kogyo Co., Ltd., Polyflon F-104) and 20 parts by weight of a liquid lubricant (n-dodecane, Japan Energy Co., Ltd.) are uniformly mixed and compressed in a cylinder A ram extrusion molding was performed to form a sheet-like PTFE molded body. Next, the formed PTFE compact was passed through a pair of rolling rolls and rolled to a thickness of 0.2 mm. Next, after the rolled PTFE molded body is heated to 150 ° C. to remove the liquid lubricant, it is stretched in the MD direction at a stretching temperature of 370 ° C. and a stretching ratio of 20 times, followed by a stretching temperature of 180 ° C. and The film was stretched in the TD direction under a stretching condition of a stretching ratio of 5 times to obtain a PTFE porous layer (thickness 45 μm, average pore diameter 3.0 μm, membrane weight 0.00975 g / m 2 per unit area). In addition, the thickness of the PTFE porous layer which is a single layer was evaluated with a dial gauge. Specifically, the thickness at at least 10 measurement points was evaluated while changing the location, and the average value of the thicknesses at each measured measurement point was taken as the thickness of the PTFE porous layer. The average pore diameter of the PTFE porous layer was evaluated by a commercially available evaluation apparatus (Perm-Porometer manufactured by Porous Materials, Inc.) capable of automatic measurement in accordance with the method defined in the American Society for Testing and Materials (ASTM) F316-86. . The membrane weight per unit area in the PTFE porous layer was determined by dividing the weight of the PTFE porous layer by the area of the layer. In order to ensure measurement accuracy, the area of the PTFE porous layer for evaluating the membrane weight per unit area was set to 5 m 2 or more.
　次に、無孔のＰＥＴフィルム（ユニチカ株式会社製、ＥＭＢＬＥＴ ＳＤ－７５、膜厚７５μｍ）を基材層として準備し、準備した基材層と、上記作製したＰＴＦＥ多孔質層とを、一対の上記ＰＴＦＥ多孔質層によって基材層が挟持されるように積層した。次に、基材層及びＰＴＦＥ多孔質層の積層体を、２８０℃の高温プレス機にて線圧２０ｋＮで６０秒間熱プレスした後、所定の形状（幅２０ｍｍ及び長さ４００ｍｍの短冊状）に裁断して、ＰＥＴの基材層と、これを挟持する一対のＰＴＦＥ多孔質層とが融着された転写シート（サンプル１）を得た。なお、裁断は、ＰＴＦＥ多孔質層のＭＤ方向と短冊の長さ方向とが一致するように行った。 Next, a non-porous PET film (Unitika Ltd., EMBLET® SD-75, film thickness 75 μm) was prepared as a base material layer, and the prepared base material layer and the prepared PTFE porous layer were paired with each other. Lamination was performed such that the base material layer was sandwiched by the PTFE porous layer. Next, the laminate of the base material layer and the PTFE porous layer was hot-pressed at a linear pressure of 20 kN for 60 seconds with a high-temperature press at 280 ° C., and then formed into a predetermined shape (strip shape having a width of 20 mm and a length of 400 mm). Cut to obtain a transfer sheet (Sample 1) in which a PET base material layer and a pair of PTFE porous layers sandwiching the PET base material layer were fused. The cutting was performed so that the MD direction of the PTFE porous layer coincided with the length direction of the strip.
　（サンプル２）
　延伸条件を変化させた以外はサンプル１と同様にして、ＰＴＦＥ多孔質層（厚さ５０μｍ、平均孔径２．９μｍ、単位面積あたりの膜重量０．０１０００ｇ／ｍ2）を作製した。次に、作製した当該ＰＴＦＥ多孔質層を用いた以外はサンプル１と同様にして、ＰＥＴの基材層と、これを挟持する一対のＰＴＦＥ多孔質層とが融着された転写シート（サンプル２）を得た。 (Sample 2)
A PTFE porous layer (thickness 50 μm, average pore diameter 2.9 μm, membrane weight 0.01000 g / m 2 per unit area) was prepared in the same manner as Sample 1 except that the stretching conditions were changed. Next, a transfer sheet (Sample 2) in which a PET base material layer and a pair of PTFE porous layers sandwiching the PET base material layer were fused in the same manner as Sample 1 except that the produced PTFE porous layer was used. )
　（サンプル３）
　延伸条件を変化させた以外はサンプル１と同様にして、ＰＴＦＥ多孔質層（厚さ６０μｍ、平均孔径２．８μｍ、単位面積あたりの膜重量０．０１０２５ｇ／ｍ2）を作製した。次に、作製した当該ＰＴＦＥ多孔質層を用いた以外はサンプル１と同様にして、ＰＥＴの基材層と、これを挟持する一対のＰＴＦＥ多孔質層とが融着された転写シート（サンプル３）を得た。 (Sample 3)
A PTFE porous layer (thickness 60 μm, average pore diameter 2.8 μm, membrane weight 0.01025 g / m 2 per unit area) was prepared in the same manner as Sample 1 except that the stretching conditions were changed. Next, a transfer sheet (Sample 3) in which a PET base material layer and a pair of PTFE porous layers sandwiching the PET base material layer were fused in the same manner as Sample 1 except that the produced PTFE porous layer was used. )
　（サンプル４）
　延伸条件を変化させた以外はサンプル１と同様にして、ＰＴＦＥ多孔質層（厚さ４０μｍ、平均孔径３．３μｍ、単位面積あたりの膜重量０．００９５０ｇ／ｍ2）を作製した。次に、作製した当該ＰＴＦＥ多孔質層を用いた以外はサンプル１と同様にして、ＰＥＴの基材層と、これを挟持する一対のＰＴＦＥ多孔質層とが融着された転写シート（サンプル４）を得た。 (Sample 4)
A PTFE porous layer (thickness 40 μm, average pore diameter 3.3 μm, membrane weight 0.00950 g / m 2 per unit area) was prepared in the same manner as Sample 1 except that the stretching conditions were changed. Next, a transfer sheet (Sample 4) in which a PET base material layer and a pair of PTFE porous layers sandwiching the PET base material layer were fused in the same manner as in Sample 1 except that the produced PTFE porous layer was used. )
　（サンプル５：比較例）
　延伸条件を変化させた以外はサンプル１と同様にして、ＰＴＦＥ多孔質層（厚さ３０μｍ、平均孔径３．５μｍ、単位面積あたりの膜重量０．００９３０ｇ／ｍ2）を作製した。次に、作製した当該ＰＴＦＥ多孔質層を用いた以外はサンプル１と同様にして、ＰＥＴの基材層と、これを挟持する一対のＰＴＦＥ多孔質層とが融着された転写シート（比較例であるサンプル５）を得た。 (Sample 5: Comparative example)
A PTFE porous layer (thickness 30 μm, average pore diameter 3.5 μm, membrane weight 0.00930 g / m 2 per unit area) was prepared in the same manner as Sample 1 except that the stretching conditions were changed. Next, a transfer sheet (comparative example) in which a PET base material layer and a pair of PTFE porous layers sandwiching the PET base material layer were fused in the same manner as in Sample 1 except that the produced PTFE porous layer was used. Sample 5) was obtained.
　（サンプル６：比較例）
　延伸条件を変化させた以外はサンプル１と同様にして、ＰＴＦＥ多孔質層（厚さ２５μｍ、平均孔径３．７μｍ、単位面積あたりの膜重量０．００９００ｇ／ｍ2）を作製した。次に、作製した当該ＰＴＦＥ多孔質層を用いた以外はサンプル１と同様にして、ＰＥＴの基材層と、これを挟持する一対のＰＴＦＥ多孔質層とが融着された転写シート（比較例であるサンプル６）を得た。 (Sample 6: Comparative example)
A PTFE porous layer (thickness 25 μm, average pore diameter 3.7 μm, membrane weight 0.00900 g / m 2 per unit area) was prepared in the same manner as Sample 1 except that the stretching conditions were changed. Next, a transfer sheet (comparative example) in which a PET base material layer and a pair of PTFE porous layers sandwiching the PET base material layer were fused in the same manner as in Sample 1 except that the produced PTFE porous layer was used. A sample 6) was obtained.
　各サンプルの特性は、以下のように評価した。 The characteristics of each sample were evaluated as follows.
　［ＰＴＦＥ多孔質層の厚さ］
　ＰＴＦＥ多孔質層の厚さは、画像解析を用いた上述の方法により評価した。 [Thickness of PTFE porous layer]
The thickness of the PTFE porous layer was evaluated by the above-described method using image analysis.
　［ＰＴＦＥ多孔質層の凝集力］
　ＰＴＦＥ多孔質層の凝集力は、１８０°引きはがし試験を用いて以下のように評価した。
　・最初に、図７に示すように、両面粘着テープ５１（日東電工株式会社製、Ｎｏ．５０００ＮＳ、厚さ１６０μｍ、幅２０ｍｍ及び長さ３５０ｍｍの短冊状）をステンレスの固定板５２の表面（貼着面）に貼着した。試験中に固定板５２の貼着面から剥離しないだけの十分な貼着力を、両面粘着テープ５１は有していた。なお、平坦な貼着面を有し、両面粘着テープ５１の面積よりも貼着面の面積が大きく、かつ試験中に変形しない十分な厚さを有する固定板５２を選択した。
　・次に、ＪＩＳ　Ｚ０２３７の項目１０．３．１『（粘着力の）試験手順』の『ａ）試験板に対する粘着力を試験する場合の手順』に準拠し、固定板５２上の両面粘着テープ５１を上記項目に定める「試験板」として、両面粘着テープ５１における固定板５２側とは反対側の面に各サンプル５３を貼着した。サンプル５３の貼着は、評価対象であるＰＴＦＥ多孔質層が両面粘着テープ５１に接するように実施した。また、サンプル５３の貼着は、固定板５２との間で長辺を一致させると共に、サンプル５３の一方の端部からの貼着部分の長さを１５０ｍｍとして実施した。なお、サンプル５３と両面粘着テープ５１とを圧着させる手動ローラ（質量２ｋｇ）の往復回数は、両面粘着テープ５１の粘着力を測定するわけではないことから、ＪＩＳ　Ｚ０２３７の規定とは異なり、一回のみとした。
　・次に、固定板５２、両面粘着テープ５１及びサンプル５３の積層体を７０℃の雰囲気に１０分間放置することで、サンプル５３に対する両面粘着テープ５１の貼着力を均質化した。その後、全体を室温（２３℃±１℃）にまで自然冷却させた。
　・次に、引張試験装置（株式会社島津製作所製、精密万能試験機オートグラフ）の下部チャック５４に固定板５２の一端を固定した後、サンプル５３の他方の端部を１８０°折り返し、折り返した他方の端部を引張試験装置の上部チャック５５に固定した。続いて、評価対象であるフッ素樹脂多孔質層を破壊しながらサンプル５３を強制的に引きはがす１８０°引きはがし試験（引張速度３００ｍｍ／分、試験温度２３±１℃、試験湿度５０±５％ＲＨ）を実施した。試験開始後、サンプル５３が両面粘着テープ５１から完全に引きはがされるまでに測定された最大応力を、フッ素樹脂多孔質層の凝集力（単位：Ｎ／２０ｍｍ）とした。 [Cohesion of PTFE porous layer]
The cohesive force of the PTFE porous layer was evaluated as follows using a 180 ° peeling test.
First, as shown in FIG. 7, the double-sided adhesive tape 51 (Nitto Denko Co., Ltd., No. 5000NS, 160 μm in thickness, 20 mm in width and 350 mm in length) is attached to the surface (affixed) of stainless steel Affixed to the wearing surface). The double-sided pressure-sensitive adhesive tape 51 had a sufficient sticking force not to peel from the sticking surface of the fixing plate 52 during the test. In addition, the fixing plate 52 which has a flat sticking surface, the area of a sticking surface larger than the area of the double-sided adhesive tape 51, and sufficient thickness which does not deform | transform during a test was selected.
-Next, in accordance with JIS Z0237 item 10.3.1 "(Adhesive strength) test procedure", "a) Procedure for testing the adhesive strength against the test plate", double-sided adhesive tape on the fixing plate 52 Each sample 53 was affixed on the opposite surface of the double-sided pressure-sensitive adhesive tape 51 to the fixed plate 52 side, with 51 as the “test plate” defined in the above item. The sample 53 was attached such that the PTFE porous layer to be evaluated was in contact with the double-sided adhesive tape 51. In addition, the sample 53 was attached by making the long side coincide with the fixed plate 52 and setting the length of the attached portion from one end of the sample 53 to 150 mm. The number of reciprocations of the manual roller (mass 2 kg) for pressing the sample 53 and the double-sided pressure-sensitive adhesive tape 51 does not measure the adhesive force of the double-sided pressure-sensitive adhesive tape 51. Only.
Next, the laminate of the fixing plate 52, the double-sided pressure-sensitive adhesive tape 51, and the sample 53 was left in an atmosphere at 70 ° C. for 10 minutes to homogenize the adhesive force of the double-sided pressure-sensitive adhesive tape 51 to the sample 53. Thereafter, the whole was naturally cooled to room temperature (23 ° C. ± 1 ° C.).
Next, after fixing one end of the fixing plate 52 to the lower chuck 54 of a tensile test apparatus (manufactured by Shimadzu Corporation, precision universal testing machine Autograph), the other end of the sample 53 was folded back by 180 °. The other end was fixed to the upper chuck 55 of the tensile test apparatus. Subsequently, a 180 ° peeling test in which the sample 53 is forcibly peeled while destroying the fluororesin porous layer to be evaluated (a tensile speed of 300 mm / min, a test temperature of 23 ± 1 ° C., a test humidity of 50 ± 5% RH) ). The maximum stress measured until the sample 53 was completely peeled off from the double-sided pressure-sensitive adhesive tape 51 after the test was started was defined as the cohesive force (unit: N / 20 mm) of the fluororesin porous layer.
　［触媒溶液の塗工性］
　　（触媒溶液の準備）
　電極触媒層に用いられる触媒物質が一般に高価であることから、本実施例では、触媒物質を含まず、カーボン粒子及び高分子電解質のみを含む模擬的な触媒溶液の塗工性を評価した。触媒物質は、転写シートにおける触媒溶液の塗工性に大きく影響しないと考えられる。このため、模擬的な触媒溶液をもって、触媒溶液の塗工性を評価することができる。模擬的な触媒溶液は、次のように準備した。最初に、カーボン粒子２５ｇ、高分子電解質（ナフィオン）１２５ｇ、イソプロピルアルコール３０２．５ｇ及び水４７．５ｇを混合して総量５００ｇの疑似触媒電極インクを得た。次に、得られた疑似触媒電極インクとイソプロピルアルコールとを、重量比１：０．５で混合希釈して、模擬的な触媒溶液を得た。この溶液の組成は、薄層化された電極触媒層を形成するために使用される低固形分濃度かつ低粘度の組成に対応する。 [Coatability of catalyst solution]
(Preparation of catalyst solution)
Since the catalyst material used for the electrode catalyst layer is generally expensive, in this example, the applicability of a simulated catalyst solution containing only the carbon particles and the polymer electrolyte was evaluated without the catalyst material. It is considered that the catalyst substance does not greatly affect the coating property of the catalyst solution on the transfer sheet. For this reason, the applicability of the catalyst solution can be evaluated with a simulated catalyst solution. A simulated catalyst solution was prepared as follows. First, 25 g of carbon particles, 125 g of polymer electrolyte (Nafion), 302.5 g of isopropyl alcohol, and 47.5 g of water were mixed to obtain a pseudo catalyst electrode ink having a total amount of 500 g. Next, the obtained pseudo catalyst electrode ink and isopropyl alcohol were mixed and diluted at a weight ratio of 1: 0.5 to obtain a simulated catalyst solution. The composition of this solution corresponds to the low solids concentration and low viscosity composition used to form the thinned electrocatalyst layer.
　　（触媒溶液の塗工性）
　準備した模擬的な触媒溶液を、各サンプルにおける一方のＰＴＦＥ多孔質層の主面（露出面）にアプリケーターを用いて塗布し、塗布膜（厚さ０．２５ｍｍ）を形成した。塗布の方向は、各サンプルの長さ方向とした。次に、１２０℃に保持した乾燥機を用いて全体を３分間加熱し、塗布膜を乾燥させて、模擬的な電極触媒層を転写シート上に形成した。塗布膜を形成する際に触媒溶液が塗布面で弾かれることがなく、かつ、形成した電極触媒層を目視により観察して亀裂等の欠陥が見られなかった場合を「塗工性／良（○）」とし、それ以外の場合を「塗工性／不可（×）」と評価した。 (Catalyst solution coating properties)
The prepared simulated catalyst solution was applied to the main surface (exposed surface) of one PTFE porous layer in each sample using an applicator to form a coating film (thickness 0.25 mm). The direction of application was the length direction of each sample. Next, the whole was heated for 3 minutes using a dryer maintained at 120 ° C., and the coating film was dried to form a simulated electrode catalyst layer on the transfer sheet. When forming the coating film, the catalyst solution is not repelled on the coating surface, and the formed electrode catalyst layer is visually observed to show no defects such as cracks. ○) ”, and other cases were evaluated as“ coatability / impossible (×) ”.
　サンプル１～６における触媒溶液の塗工性は、全て、良（○）であった。 The coating properties of the catalyst solutions in Samples 1 to 6 were all good (◯).
　サンプル１～６とは別に、非多孔質である無孔のＰＴＦＥシートを転写シートとして準備した（比較例であるサンプル７）。サンプル７に対して触媒溶液の塗工性を評価したところ、塗布の際に触媒溶液が弾かれてしまい、電極触媒層自体の形成ができなかった。 Separately from samples 1 to 6, a nonporous non-porous PTFE sheet was prepared as a transfer sheet (sample 7 as a comparative example). When the coating property of the catalyst solution was evaluated for Sample 7, the catalyst solution was repelled during the coating, and the electrode catalyst layer itself could not be formed.
　［熱転写特性］
　模擬的な電極触媒層を形成したサンプルについて、熱転写特性、より具体的には、電極触媒層の安定した熱転写が可能であるか、を以下のように評価した。 [Thermal transfer characteristics]
A sample on which a simulated electrode catalyst layer was formed was evaluated for thermal transfer characteristics, more specifically, whether stable thermal transfer of the electrode catalyst layer was possible as follows.
　電極触媒層を熱転写する部材として、粘着テープ（日東電工株式会社製、Ｎｏ．３６０ＵＬ、厚さ６５μｍ、幅２０ｍｍ×長さ１５０ｍｍの短冊状）を準備した。次に、粘着テープの粘着面と、サンプル上に形成した電極触媒層とが互いに接するように、粘着テープとサンプルとを積層した。積層は、電極触媒層の全体が粘着テープに接するように行った。次に、積層体の長さ方向に質量２ｋｇの手動ローラを一往復させて、粘着テープとサンプルとを圧着させた。手動ローラには、ＪＩＳ　Ｚ０２３７の項目１０．３．１に定められたものを使用した。次に、室温、１２０℃、１５０℃又は１８０℃に設定した熱プレス機を用いて、線圧４．５ｋＮの加圧条件で３０秒間、積層体を熱プレスした。次に、積層体を室温に戻した後、サンプルを手で剥離して、粘着テープに転写された電極触媒層の状態を目視により観察した。観察の結果、電極触媒層に変形、損傷、表面の欠落等の欠陥がみられなかった場合を「熱転写特性／良（○）」とし、部分的に欠陥がみられた場合を「熱転写特性／電極触媒層の使用条件により可（△）」とし、全体的に欠陥がみられた場合を「熱転写特性／不可（×）」とした。 An adhesive tape (manufactured by Nitto Denko Corporation, No. 360UL, 65 μm in thickness, 20 mm in width × 150 mm in length) was prepared as a member for thermally transferring the electrode catalyst layer. Next, the adhesive tape and the sample were laminated so that the adhesive surface of the adhesive tape and the electrode catalyst layer formed on the sample were in contact with each other. Lamination was performed such that the entire electrode catalyst layer was in contact with the adhesive tape. Next, a manual roller having a mass of 2 kg was reciprocated once in the length direction of the laminate, and the adhesive tape and the sample were pressure bonded. As the manual roller, the one specified in JIS Z0237, item 10.3.1 was used. Next, the laminate was hot-pressed for 30 seconds under a pressurizing condition of a linear pressure of 4.5 kN using a hot press set at room temperature, 120 ° C., 150 ° C. or 180 ° C. Next, after returning a laminated body to room temperature, the sample was peeled by hand and the state of the electrode catalyst layer transferred to the adhesive tape was visually observed. As a result of observation, when the electrode catalyst layer did not show any defects such as deformation, damage, surface loss, etc., it was defined as “thermal transfer characteristics / good (◯)”, and when defects were partially observed, “thermal transfer characteristics / Depending on the conditions of use of the electrode catalyst layer, “Yes (Δ)” was given, and when a defect was found overall, “thermal transfer characteristics / impossible (x)”.
　サンプル１～４の熱転写特性は、室温、１２０℃、１５０℃及び１８０℃のいずれの熱転写条件においても良（○）であった。比較例であるサンプル５の熱転写特性は、１５０℃の熱転写条件において可（△）となった。また、比較例であるサンプル６の熱転写特性は、１５０℃及び１８０℃の熱転写条件において不可（×）となった。サンプル５及びサンプル６では、熱転写特性が可、又は不可となった高温での熱転写条件において、ＰＴＦＥ多孔質層の一部が熱転写時に凝集破壊して、転写された電極触媒層の表面に付着していた。転写後の電極触媒層を使用するためには、付着したＰＴＦＥ片を除去する必要がある。しかし、ＰＴＦＥ片が付着していた箇所では電極触媒層に変形、亀裂及び欠落（凹み）が生じており、電極触媒層としての面内方向の均質性は大きく低下した状態であった。 The thermal transfer characteristics of Samples 1 to 4 were good (◯) under any thermal transfer conditions of room temperature, 120 ° C., 150 ° C., and 180 ° C. The thermal transfer characteristic of Sample 5 as a comparative example was acceptable (Δ) under the thermal transfer condition of 150 ° C. Further, the thermal transfer characteristic of Sample 6 as a comparative example was not possible (x) under the thermal transfer conditions of 150 ° C. and 180 ° C. In Sample 5 and Sample 6, a part of the PTFE porous layer is agglomerated and destroyed at the time of thermal transfer under the high-temperature thermal transfer conditions in which thermal transfer characteristics are enabled or disabled, and adhere to the surface of the transferred electrode catalyst layer. It was. In order to use the electrode catalyst layer after transfer, it is necessary to remove the attached PTFE pieces. However, deformation, cracks and omissions (dents) occurred in the electrode catalyst layer at the location where the PTFE piece was attached, and the in-plane homogeneity as the electrode catalyst layer was greatly reduced.
　評価結果を、以下の表１にまとめる。 The evaluation results are summarized in Table 1 below.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　本開示の転写シートは、例えば、燃料電池等の電気化学素子が備える電極触媒層の転写に使用できる。 The transfer sheet of the present disclosure can be used, for example, for transferring an electrode catalyst layer provided in an electrochemical element such as a fuel cell.

Claims (11)

  1. 　層を転写するための転写シートであって、
    　基材層と、前記基材層に接合された、前記基材層を挟持する一対のフッ素樹脂多孔質層と、を備え、
    　少なくとも一方の前記フッ素樹脂多孔質層が、１．８Ｎ／２０ｍｍ以上の凝集力を有する、転写シート。     A transfer sheet for transferring the layer,
    A base material layer, and a pair of fluororesin porous layers that are bonded to the base material layer and sandwich the base material layer,
    The transfer sheet in which at least one of the fluororesin porous layers has a cohesive force of 1.8 N / 20 mm or more.
  2. 　前記少なくとも一方のフッ素樹脂多孔質層がポリテトラフルオロエチレン多孔質層である、請求項１に記載の転写シート。 The transfer sheet according to claim 1, wherein the at least one fluororesin porous layer is a polytetrafluoroethylene porous layer.
  3. 　前記少なくとも一方のフッ素樹脂多孔質層の厚さが１００μｍ以下である、請求項１又は２に記載の転写シート。 The transfer sheet according to claim 1 or 2, wherein the thickness of the at least one fluororesin porous layer is 100 µm or less.
  4. 　前記少なくとも一方のフッ素樹脂多孔質層の平均孔径が０．１μｍ～２０μｍである、請求項１～３のいずれかに記載の転写シート。 4. The transfer sheet according to claim 1, wherein an average pore diameter of the at least one fluororesin porous layer is 0.1 μm to 20 μm.
  5. 　前記基材層が熱可塑性樹脂層である、請求項１～４のいずれかに記載の転写シート。 The transfer sheet according to any one of claims 1 to 4, wherein the base material layer is a thermoplastic resin layer.
  6. 　前記熱可塑性樹脂層を構成する熱可塑性樹脂の融点が２８０℃以下である、請求項５に記載の転写シート。 The transfer sheet according to claim 5, wherein the thermoplastic resin constituting the thermoplastic resin layer has a melting point of 280 ° C. or lower.
  7. 　前記熱可塑性樹脂層を構成する熱可塑性樹脂が、ポリエステル、ポリアセタール、ポリエチレン、超高分子量ポリエチレン及びポリプロピレンから選ばれる少なくとも１種である、請求項５又は６に記載の転写シート。 The transfer sheet according to claim 5 or 6, wherein the thermoplastic resin constituting the thermoplastic resin layer is at least one selected from polyester, polyacetal, polyethylene, ultrahigh molecular weight polyethylene and polypropylene.
  8. 　前記基材層と、前記一対のフッ素樹脂多孔質層とが融着により接合されている、請求項１～７のいずれかに記載の転写シート。 The transfer sheet according to any one of claims 1 to 7, wherein the base material layer and the pair of fluororesin porous layers are joined by fusion bonding.
  9. 　前記転写シートの厚さが１５μｍ～４００μｍである、請求項１～８のいずれかに記載の転写シート。 The transfer sheet according to any one of claims 1 to 8, wherein the transfer sheet has a thickness of 15 μm to 400 μm.
  10. 　前記転写シートによって転写される層が電極触媒層である、請求項１～９のいずれかに記載の転写シート。 10. The transfer sheet according to claim 1, wherein the layer transferred by the transfer sheet is an electrode catalyst layer.
  11. 　請求項１～１０のいずれかに記載の転写シートと、電極触媒層とを備え、
    　前記電極触媒層が、前記少なくとも一方のフッ素樹脂多孔質層の上に配置されている、電極触媒層付きシート。     A transfer sheet according to any one of claims 1 to 10 and an electrode catalyst layer,
    A sheet with an electrode catalyst layer, wherein the electrode catalyst layer is disposed on the at least one fluororesin porous layer.
PCT/JP2019/020763 2018-05-30 2019-05-24 Transfer sheet for transferring layer and sheet with electrode catalyst layer WO2019230610A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
KR1020207037340A KR20210018319A (en) 2018-05-30 2019-05-24 A sheet having a transfer sheet and an electrode catalyst layer for transferring a layer
CN201980036413.6A CN112203855A (en) 2018-05-30 2019-05-24 Transfer sheet for transfer layer and sheet with electrode catalyst layer

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2018103320 2018-05-30
JP2018-103320 2018-05-30

Publications (1)

Publication Number Publication Date
WO2019230610A1 true WO2019230610A1 (en) 2019-12-05

Family

ID=68696959

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2019/020763 WO2019230610A1 (en) 2018-05-30 2019-05-24 Transfer sheet for transferring layer and sheet with electrode catalyst layer

Country Status (4)

Country Link
JP (1) JP7324615B2 (en)
KR (1) KR20210018319A (en)
CN (1) CN112203855A (en)
WO (1) WO2019230610A1 (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002184415A (en) * 2000-10-18 2002-06-28 General Motors Corp <Gm> Method of preparing membrane electrode assembly
JP2015096325A (en) * 2013-10-11 2015-05-21 日東電工株式会社 Thin layer transfer sheet, thin layer transfer sheet with electrode catalyst layer, method of producing thin layer transfer sheet, and method of producing membrane electrode assembly
JP2017013468A (en) * 2015-07-06 2017-01-19 日東電工株式会社 Sheet for transferring layer and sheet having electrode catalyst layer using the same
WO2018101176A1 (en) * 2016-11-29 2018-06-07 日東電工株式会社 Transfer sheet for layer transfer and sheet with electrode catalyst layer

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008103251A (en) 2006-10-20 2008-05-01 Toyota Motor Corp Thermal transfer method of catalyst layer to electrolyte membrane, and its device
JP5508880B2 (en) * 2010-02-01 2014-06-04 日東電工株式会社 Double-sided adhesive tape and method for producing the same
US20130045438A1 (en) * 2010-03-26 2013-02-21 Yasuhiro Haba Producing method of fuel cell membrane electrode assembly and producing apparatus of the same
JP2013073892A (en) 2011-09-29 2013-04-22 Toppan Printing Co Ltd Method for manufacturing membrane electrode assembly for fuel cell
TW201420344A (en) * 2012-09-21 2014-06-01 Nippon Synthetic Chem Ind Polyvinyl alcohol-based film and manufacturing method thereof, laminate for heat transfer printing using polyvinyl alcohol-based film and heat transfer printing method using same
KR102313154B1 (en) * 2014-03-31 2021-10-15 도레이 카부시키가이샤 Substrate film, catalyst transfer sheet, method for producing membrane electrode assembly, and method for producing catalyst layer-coated electrolyte membrane

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002184415A (en) * 2000-10-18 2002-06-28 General Motors Corp <Gm> Method of preparing membrane electrode assembly
JP2015096325A (en) * 2013-10-11 2015-05-21 日東電工株式会社 Thin layer transfer sheet, thin layer transfer sheet with electrode catalyst layer, method of producing thin layer transfer sheet, and method of producing membrane electrode assembly
JP2017013468A (en) * 2015-07-06 2017-01-19 日東電工株式会社 Sheet for transferring layer and sheet having electrode catalyst layer using the same
WO2018101176A1 (en) * 2016-11-29 2018-06-07 日東電工株式会社 Transfer sheet for layer transfer and sheet with electrode catalyst layer

Also Published As

Publication number Publication date
CN112203855A (en) 2021-01-08
JP2019209687A (en) 2019-12-12
KR20210018319A (en) 2021-02-17
JP7324615B2 (en) 2023-08-10

Similar Documents

Publication Publication Date Title
KR102239198B1 (en) Sheet for transferring thin layer, thin-layer-transferring sheet with electrode catalyst layer, process for producing sheet for transferring thin layer, and process for producing membrane electrode assembly
JP5122149B2 (en) Manufacturing method of membrane electrode assembly for polymer electrolyte fuel cell
US10374245B2 (en) Manufacturing method for reinforced electrolyte membrane and manufacturing apparatus of manufacturing the same
JP2010067493A (en) Manufacturing method for membrane-electrode assembly, membrane-electrode assembly, and solid polymer fuel cell
US20200287220A1 (en) Method for producing gas diffusion electrode substrate and fuel cell
US9005839B2 (en) Method for laminating composite sheet using release film, laminate obtained by the method, and release film for use in the method
JP6345863B2 (en) Sheet for transferring layer and sheet with electrode catalyst layer
JP5412860B2 (en) Manufacturing apparatus and manufacturing method for membrane catalyst layer assembly, and manufacturing apparatus and manufacturing method for membrane electrode assembly
WO2019230610A1 (en) Transfer sheet for transferring layer and sheet with electrode catalyst layer
JP5439710B2 (en) Electrolyte membrane with catalyst layer and method for producing the same
WO2018122888A1 (en) Transfer sheet for transferring layer, and sheet equipped with electrode catalyst layer
JP6553962B2 (en) Sheet for Transferring Layer and Sheet Having Electrode Catalyst Layer Using the Same
TWI739785B (en) Transfer sheet for layer transfer and sheet with electrode catalyst layer
JP5699348B2 (en) Manufacturing apparatus and manufacturing method for membrane catalyst layer assembly, and manufacturing apparatus and manufacturing method for membrane electrode assembly
EP3832766B1 (en) Method of manufacturing and device for manufacturing membrane-catalyst assembly
JP6201398B2 (en) Transfer sheet with mask film / base film, method for producing transfer sheet with mask film / base film, and method for producing catalyst layer sheet
KR20200119203A (en) Method for manufacturing membrane electrode assembly for fuel cell
JP2010123372A (en) Method for manufacturing membrane electrode assembly for solid polymer fuel cell and membrane electrode assembly

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19812176

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 20207037340

Country of ref document: KR

Kind code of ref document: A

122 Ep: pct application non-entry in european phase

Ref document number: 19812176

Country of ref document: EP

Kind code of ref document: A1