Framework or structure of a porous transport layer and heat treatment apparatus comprising the same

Abstract

The present invention provides a framework or structure for manufacturing a porous transport layer and a heat treatment apparatus including the same. The framework or structure for manufacturing a titanium-based porous transport layer applied to a heat treatment apparatus minimizes contamination of a receiving portion, a loading portion, a porous transport layer molding sheet, etc., and minimizes deviation in physical properties even when a plurality of porous transport layers are stacked and processed.

Description

Technical Field

[0001] This disclosure relates to a frame or structure for manufacturing a porous transport layer and a heat treatment apparatus including the frame or structure. Background Technology

[0002] The anode in the polymer electrolyte membrane (PEM) water electrolysis system is subjected to harsh conditions, and a porous transport layer (PTL) made of titanium-based material instead of carbon-based material is used. This PTL is located between the anode and the separator and helps induce the water electrolysis and oxygen generation reactions.

[0003] During the manufacturing process of PTL, various factors may lead to the mixing of impurities or quality deviations.

[0004] The information disclosed in this background section is intended only to enhance the understanding of the background technology of this disclosure, and therefore may contain information that does not constitute prior art known to those skilled in the art in this country. Summary of the Invention

[0005] Various aspects of this disclosure are intended to provide frameworks and structures that can be used semi-permanently, minimize temperature deviations applied to porous transport layers (PTLs), and minimize impurities in the PTLs.

[0006] The purpose of this disclosure is not limited to the foregoing. The purpose of this disclosure will become clearer from the following description, and can be achieved by the means disclosed in the claims and combinations thereof.

[0007] In one aspect, this disclosure provides a framework for manufacturing a porous transport layer, the framework serving as a framework for manufacturing a titanium-based porous transport layer for use in a heat treatment apparatus, and the framework comprising: at least one receiving portion including an inlet arranged such that the porous transport layer enters and exits the at least one receiving portion through the inlet; a wall closing the at least one receiving portion other than the inlet; and an opening / closing portion configured to regulate the opening and closing of the inlet, wherein the components forming the at least one receiving portion, the wall, and the opening / closing portion comprise at least one of molybdenum, tungsten, or zirconium.

[0008] In one exemplary embodiment of this disclosure, the framework may further include a path in internal fluid communication with at least one receiving portion to generate a gas flow.

[0009] In another exemplary embodiment of this disclosure, the wall may include an outlet in fluid communication with the path.

[0010] In yet another exemplary embodiment of this disclosure, the diameter of the outlet may be 3 mm to 10 mm.

[0011] In yet another exemplary embodiment of this disclosure, the path may be in fluid communication with a predetermined gap between the inlet and the open / closed portion.

[0012] In another exemplary embodiment of this disclosure, at least one receiving portion may include a plurality of receiving portions aligned in one direction for stacking, the space in the plurality of receiving portions may be formed by a plurality of receiving members aligned in one direction and walls respectively connected to the side portions of the plurality of receiving members, the plurality of receiving portions may have a shape having a predetermined margin compared to the shape of the porous transmission layer; and the height of the plurality of receiving portions may be 0.5 mm to 1.0 mm greater than the thickness of the porous transmission layer.

[0013] In a further exemplary embodiment of this disclosure, the wall thickness may be from 0.5 mm to 2.0 mm.

[0014] In another exemplary embodiment of this disclosure, the minimum distance between the inner wall of the heat treatment apparatus and the frame may be equal to or greater than 70 cm.

[0015] In another aspect, this disclosure provides a structure for manufacturing a porous transport layer, the structure serving as a support for manufacturing a titanium-based porous transport layer for use in a heat treatment apparatus, and the structure comprising: a plurality of loading portions arranged such that the porous transport layer is loaded thereon; a support supporting the plurality of loading portions to form a predetermined interval between the plurality of loading portions; and a capping portion configured to close the plurality of loading portions to separate them from the plurality of loading portions by the predetermined interval, wherein the plurality of loading portions, the support, and the capping portion comprise at least one of molybdenum or tungsten.

[0016] In an exemplary embodiment of this disclosure, the cap portion may include an outlet.

[0017] In another exemplary embodiment of this disclosure, the cover portion may include an internal space and have a surface configured to be open, and the cover portion may receive the loading portion and the support through the surface, and then be closed such that a predetermined gap is formed between the cover portion and the surface that contacts the cover portion.

[0018] In another aspect, this disclosure provides a heat treatment apparatus for manufacturing a porous transport layer comprising a frame or structure.

[0019] Other aspects and exemplary implementations of this disclosure are discussed below.

[0020] The above and other features of this disclosure are discussed below. Attached Figure Description

[0021] The above and other features of this disclosure will now be described only by way of example, and therefore are not intended to limit this disclosure, wherein:

[0022] Figure 1 This is a schematic diagram illustrating a framework for fabricating a porous transport layer according to an exemplary embodiment of the present disclosure;

[0023] Figure 2 This is a schematic diagram illustrating a structure for fabricating a porous transport layer according to another exemplary embodiment of the present disclosure;

[0024] Figure 3 This is a schematic cross-sectional view briefly illustrating a frame for fabricating a porous transport layer according to an exemplary embodiment of the present disclosure;

[0025] Figure 4 This is a schematic cross-sectional view briefly illustrating a structure for fabricating a porous transport layer according to another exemplary embodiment of the present disclosure; and

[0026] Figure 5 It is a schematic cross-sectional view of the structure based on the comparative scale.

[0027] It should be understood that the accompanying drawings are not necessarily drawn to scale and present slightly simplified representations of various preferred features illustrating the basic principles of this disclosure. Specific design features of this disclosure (including, for example, specific dimensions, orientations, locations, and shapes) will be determined in part by the specific intended application and environment of use.

[0028] In the accompanying drawings, reference numerals throughout the drawings refer to the same or equivalent parts of this disclosure. Detailed Implementation

[0029] The above-described objectives, other objectives, advantages, and features of this disclosure will become apparent from the following description of embodiments given with reference to the accompanying drawings. However, this disclosure is not limited to the embodiments disclosed herein and may be implemented in various different forms. These embodiments are provided so that the description of this disclosure will be thorough and will fully convey the scope of this disclosure to those skilled in the art.

[0030] In the following description of the embodiments, the same elements are denoted by the same reference numerals, even when described in different drawings. In the drawings, the dimensions of the structures may be enlarged compared to their actual dimensions for clarity of description. In the following description of the embodiments, terms such as "first" and "second" may be used to describe various elements, but are not limiting of these elements. These terms are only used to distinguish one element from other elements. For example, without departing from the scope and spirit of this disclosure, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element. Singular expressions may encompass plural expressions unless they have a significantly different meaning in the context.

[0031] In the following description of the embodiments, terms such as “including,” “comprising,” and “having” should be interpreted as indicating the presence of the features, quantities, steps, operations, elements, or portions or combinations thereof stated in the description, and do not preclude the presence or addition of one or more other features, quantities, steps, operations, elements, portions, or combinations thereof. Furthermore, it should be understood that when a portion such as a layer, film, region, or plate is said to be “on” another portion, that portion may be “directly located” on the other portion, or other portions may be located between the two portions. Similarly, it will be understood that when a portion such as a layer, film, region, or plate is said to be “below” another portion, that portion may be “directly located” below the other portion, or other portions may be inserted between the two portions.

[0032] In this article, depending on the context, the comma “,” can be interpreted as “and” or “or”, and if the element is listed with “or” at the end of the comma, the comma can be interpreted as “or”.

[0033] All numerical values, specifications, and / or expressions used in this specification to represent the amounts of components, reaction conditions, polymer compositions, and blends are approximate values, reflecting the various uncertainties that arise when these values ​​are obtained from substantially different sources, and therefore will be understood to be modified by the term "about" unless otherwise stated. Furthermore, it should be understood that if a range of values ​​is disclosed in this specification, such a range includes all consecutive values ​​from the minimum to the maximum value of that range, unless otherwise stated. Additionally, if such a range refers to integers, the range includes all integers from the minimum to the maximum integer, unless otherwise stated.

[0034] Frame 100 for fabricating porous transport layers

[0035] refer to Figure 1 and Figure 3According to an exemplary embodiment of the present disclosure, the frame 100 for manufacturing the porous transport layer 1 is a frame 100 for manufacturing a titanium-based porous transport layer 1 applied to a heat treatment apparatus 200, and the frame 100 may include at least one receiving portion 10, the at least one receiving portion 10 including an inlet arranged such that the porous transport layer 1 enters and exits the at least one receiving portion 10 through the inlet; a wall 20 configured to close at least one receiving portion 10 except for the inlet; and an opening / closing portion 30 configured to regulate the opening and closing of the inlet, and the components forming at least one receiving portion 10, wall 20 and opening / closing portion 30 may include materials selected from the group consisting of molybdenum, tungsten and combinations thereof.

[0036] The components forming the receiving portion 10, the wall 20, and the opening / closing portion 30 may comprise the same material, and may include, for example, molybdenum or tungsten. In this case, the contamination resistance of the porous transport layer 1 can be further improved.

[0037] The frame 100 may further include a path 40 that is in internal fluid communication with the receiving portion 10 and generates gas flow.

[0038] like Figure 3 As shown, multiple receiving portions 10 can be aligned and stacked in one direction, and the space in the receiving portion 10 can be formed by multiple receiving members 11 stacked at predetermined intervals in one direction and walls 20 respectively connected to the side portions of the receiving members 11. If the receiving member 11 has a shape corresponding to the porous transmission layer 1 (i.e., square), the walls 20 can be connected to contact three sides of the receiving member 11.

[0039] Here, 2 to 50 receiving sections 10 can be set, and the number of receiving sections 10 can be changed according to the internal space of the heat treatment device 200.

[0040] The lower part of the receiving member 11 of the lowermost receiving portion 10 (i.e., the lower end of the frame 100 for manufacturing the porous transport layer 1) can define an open lower space extending toward the wall 20, and the base plate member 201 of the heat treatment apparatus 200 can be located in this lower space. The lower space can be closed to include only the base plate member 201.

[0041] The receiving portion 10 can have a shape with a predetermined margin compared to the shape of the porous transport layer 1, and can have a height that is 0.5 mm to 1.0 mm greater than the thickness of the porous transport layer 1. Utilizing this height of the receiving portion 10, organic matter can be facilitated from being discharged from the porous transport layer sheet, internal contamination can be minimized, and space utilization can be optimized.

[0042] Wall 20 may include outlet 21 in fluid communication with path 40.

[0043] The diameter of outlet 21 can be from 3 mm to 10 mm. By utilizing the diameter of outlet 21, the inflow of contaminants into receiving section 10 can be minimized, and the discharge of organic matter that may be contained in the porous transport layer molded sheet can be facilitated.

[0044] The thickness of the wall 20 can be from 0.5 mm to 2.0 mm. By utilizing the thickness of the wall 20, high-temperature deformation and appearance degradation of the porous transport layer 1 can be prevented, and raw materials can be used continuously with minimal raw material costs.

[0045] like Figure 1 As shown, the opening / closing section 30 can open and close the entrance of the receiving section 10. The walls 20 located on one side and the other side of the entrance of the receiving section 10 may include separate slide rails, and the two sides of the opening / closing section 30 move along the slide rails to close the entrance. Alternatively, the opening / closing section 30 and the wall 20 at the entrance are connected by separate hinges.

[0046] When the inlet is closed by the open / close section 30 to perform heat treatment, a predetermined gap may exist between the open / close section 30 and the wall 20, and the gas in the receiving section 10 may be discharged without a separate outlet 21. The size of the gap may be from 1 mm to 10 mm. By utilizing the size of the gap, the inflow of contaminants into the receiving section 10 can be minimized and the discharge of organic matter that may be contained in the porous transport layer molded sheet can be facilitated.

[0047] Even if the open / close section 30 is positioned to close the inlet, the multiple receiving sections 10 within the frame 100 can still be fluidly connected to each other, ensuring gas flow and defining the path 40 through which the gas can move.

[0048] Path 40 may correspond to a predetermined gap between the inlet of receiving section 10 and opening / closing section 30. Path 40 may be in fluid communication with the gap between opening / closing section 30 and wall 20 and / or outlet 21.

[0049] During heat treatment and sintering operations, the interior of the frame 100, which is closed by the opening / closing section 30, may have a different vacuum level than the exterior, and therefore, gas flow may occur between the path 40 and the outlet 21, between the path 40 and the gap between the opening / closing section 30 and the wall.

[0050] The minimum distance from the inner wall of the heat treatment apparatus 200 to the frame 100 can be 70 cm or more but 140 cm or less. This distance can prevent over-sintering and ensure uniform heat treatment.

[0051] The minimum distance from the inner wall of the heat treatment apparatus 200 to the porous transport layer forming sheet in the receiving section 10 can be 100 cm or more but 170 cm or less. This distance can prevent over-sintering and ensure uniform heat treatment.

[0052] The multiple receiving components 11, walls 20, and related components of the opening / closing parts of the frame 100 can be assembled by stamping units, fastening units, joining units, welding units, etc.

[0053] Structure 101 for fabricating porous transport layers

[0054] refer to Figure 2 and Figure 4 According to another exemplary embodiment of this disclosure, the structure 101 for manufacturing the porous transport layer 1 is a structure 101 for manufacturing a titanium-based porous transport layer 1 applied to a heat treatment apparatus 200, and the structure 101 may include: a plurality of loading portions 15 configured to load the porous transport layer 1 thereon; a support 16 configured to support the loading portions 15 to form a predetermined interval between the loading portions 15; and a capping portion 25 configured to close the loading portions 15 to be spaced apart from the loading portions 15 by a predetermined interval, and the loading portions 15, the support 16 and the capping portion 25 may include materials selected from the group consisting of molybdenum, tungsten and combinations thereof.

[0055] The loading portion 15, the support member 16, and the capping portion 25 may be made of the same material, and may include, for example, molybdenum or tungsten. In this case, the contamination resistance of the porous transport layer 1 can be further improved.

[0056] like Figure 4 As shown, multiple loading portions 15 can be aligned in one direction to stack, and the space on the loading portions 15 can be formed by the multiple loading portions 15 and the support members 16 disposed between the loading portions 15. If the loading portion 15 has a shape corresponding to the porous transmission layer 1 (i.e., square), the support members 16 can be disposed on one side and the other side of the loading portion 15.

[0057] Here, 2 to 50 loading sections 15 can be set, and the number of loading sections 15 can be changed according to the internal space of the heat treatment device 200.

[0058] The lower portion of the lowermost loading portion 15 among the plurality of loading portions 15 (i.e., the lower end of the structure 101 for manufacturing the porous transport layer 1) may define an open lower space extending toward the cap portion 25, and the base plate member 201 of the heat treatment apparatus 200 may be located in this lower space. The lower space may be closed to include only the base plate member 201.

[0059] The spacing between the loading portions 15 can be 0.5 mm to 1.0 mm larger than the thickness of the porous transport layer 1. By utilizing the spacing between the loading portions 15, the discharge of organic matter from the porous transport layer sheet can be facilitated, internal contamination can be minimized, and space utilization can be optimized.

[0060] The capping portion 25 may include a separate outlet 26.

[0061] The diameter of outlet 26 can be from 3 mm to 10 mm. By utilizing this diameter of outlet 26, the inflow of contaminants into loading section 15 can be minimized, and the discharge of organic matter that may be contained in the porous transport layer molded sheet can be facilitated.

[0062] The thickness of the capping portion 25 can be from 0.5 mm to 2.0 mm. This thickness of the capping portion 25 can prevent high-temperature deformation and appearance degradation of the porous transport layer 1, and enable continuous use of raw materials with minimal raw material cost.

[0063] The cover portion 25 can open or close the loading portion 15 and includes an internal space formed by opening one surface of the cover portion 25.

[0064] When the loading portion 15 is closed by the cover portion 25, the loading portion 15 can be located in the interior space of the cover portion 25 and can be closed to contact the area corresponding to the ground or the area corresponding to the bottom surface of the heat treatment apparatus 200.

[0065] When the loading portion 15 is closed via the cap portion 25 to perform heat treatment, a predetermined gap exists between the cap portion 25 and the adjacent surface (i.e., the bottom surface of the heat treatment apparatus 200), allowing internal gases to escape without a separate outlet 26. The size of the gap can be from 2 mm to 10 mm. This gap size minimizes the inflow of contaminants into the loading portion 15 and facilitates the removal of organic matter that may be contained within the porous transport layer molded sheet.

[0066] The inner surface of the capping portion 25 may be spaced apart from the loading portion 15 at specified intervals, and includes a path through which gas can move.

[0067] During heat treatment and sintering operations, the interior of the structure 101, which is closed by the capping portion 25, may have a different vacuum level than the exterior, and therefore, gas flow may occur between the path and the outlet 26, between the path and the gap, etc.

[0068] The minimum distance from the inner wall of the heat treatment apparatus 200 to the structure 101 can be 70 cm or more but 140 cm or less. This distance can prevent over-sintering and ensure uniform heat treatment.

[0069] The minimum distance from the inner wall of the heat treatment apparatus 200 to the porous transport layer forming sheet in the loading section 15 can be 100 cm or more but 170 cm or less. This distance can prevent over-sintering and ensure uniform heat treatment.

[0070] The various loading parts 15, support parts 16, and related components of the cover part of the structure 101 can be assembled by stamping units, fastening units, joining units, welding units, etc., and in the case of molybdenum, they can also be manufactured by metal 3D printing.

[0071] Figure 5 A structure according to a comparative example is shown, comprising a refractory unit having a plurality of loading portions 10a on a base plate member 201a within a heat treatment apparatus 200a, and a porous transfer layer 1 loaded on the loading portions 10a. When passed according to... Figure 5 When the comparative structure shown was subjected to heat treatment and sintering, it was confirmed that the organic matter contamination contained in the porous transport layer 1 covered the entire area of ​​the refractory unit structure, and the carbon composition of the base plate member 201a diffused into the interior of the loading part 10a, resulting in a slightly higher impurity content in the porous transport layer than the reference, and some deviations in physical properties.

[0072] According to an exemplary embodiment of this disclosure, when the frame 100 and the structure 101 used to manufacture the porous transport layer 1 are subjected to heat treatment and sintering, due to the use of molybdenum and / or tungsten and the unique structure of the frame 100 or structure 101, it is confirmed that mixing of the components of the base plate member 201 is prevented. Due to the binder, the degree of carbon contamination and contamination of the porous transport layer 1 by other elements is very low, and deviations in physical properties are minimized compared to the comparative example. The heat treatment and sintering can correspond to the debinding and sintering operations described below.

[0073] Heat treatment apparatus for manufacturing porous transport layers 200

[0074] refer to Figure 3 and Figure 4 According to an exemplary embodiment of the present disclosure, a heat treatment apparatus 200 for manufacturing a porous transport layer 1 may include the aforementioned frame 100 for manufacturing the porous transport layer 1 or a structure 101 for manufacturing the porous transport layer 1.

[0075] The heat treatment apparatus 200 may include a conventional heating unit and may include an electric furnace, a gas furnace or other types.

[0076] The heat treatment apparatus 200 may include a base plate member 201, and a frame 100 for manufacturing the porous transport layer 1 or a structure 101 for manufacturing the porous transport layer 1 may be arranged on the base plate member 201.

[0077] The minimum distance between the inner wall of the heat treatment apparatus 200 and the frame 100 or structure 101 can be 70 cm or more but 140 cm or less. Additionally, the minimum distance between the inner wall of the heat treatment apparatus 200 and the porous transport layer forming sheet arranged in the frame 100 or structure 101 can be 100 cm or more but 170 cm or less. These distances prevent over-sintering and ensure uniform heat treatment.

[0078] The heat treatment apparatus 200 may include a pressurizer, a pressure reducer, a vacuum pump, a gas inlet, a gas outlet, etc., and may inject inert gas or adjust the vacuum level according to the processing operation.

[0079] Heat treatment via heat treatment apparatus 200 may include:

[0080] (a) The porous transmission layer molding sheet is disposed in the receiving portion 10 of the frame 100 or on the loading portion 15 of the structure 101;

[0081] (b) Solvents and adhesives are removed from the porous transport layer sheet by closing the receiving portion 10 with the opening / closing portion 30 or closing the loading portion 15 with the capping portion 25 and then performing heat treatment; and

[0082] (c) The product obtained from sintering operation (b).

[0083] The porous transport layer (PTL) can include, for example, metals, binders, dispersants, solvents, etc., used for the PTL. Metals used for the PTL can include titanium, nickel, stainless steel, etc. Binders can include polyvinyl butyral, polyvinyl alcohol, polyvinyl chloride, polyvinyl acetate, polyacrylonitrile, etc. Dispersants can include water, ethanol, methanol, isopropanol, xylene, cyclohexanone, acetone, methyl ethyl ketone, etc. Solvents can include alcohols or substituted / unsubstituted benzene compounds.

[0084] The heat treatment temperature of operation (b) can be from 300°C to 700°C, and can be performed in an inert gas atmosphere or an argon atmosphere.

[0085] Sintering in operation (c) can be performed at temperatures from 900°C to 1500°C and at 1×10⁻⁶ ℃. -8 Up to 1×10 -5 Performed under the vacuum level of Torr.

[0086] After operation (c), the furnace can be cooled while maintaining the vacuum level.

[0087] As is evident from the above description, according to exemplary embodiments of the present disclosure, the frame and structure for manufacturing porous transport layers can minimize contamination of the receiving portion, loading portion, porous transport layer molding sheet, etc., and can minimize deviations in physical properties even when multiple porous transport layers are stacked and processed.

[0088] The effects of this disclosure are not limited to those described above. It should be understood that the effects of this disclosure include all effects that can be inferred from the above description.

[0089] This disclosure has been described in detail with reference to exemplary embodiments thereof. However, those skilled in the art will understand that changes may be made to these embodiments without departing from the principles and spirit of this disclosure, the scope of which is limited by the appended claims and their equivalents.

Claims

1. A frame for fabricating a porous transport layer, the frame serving as a frame for fabricating a titanium-based porous transport layer for use in a heat treatment apparatus, the frame comprising: At least one receiving portion, the at least one receiving portion including an inlet, the inlet being arranged such that a porous transmission layer enters and exits the at least one receiving portion through the inlet; A wall that closes off at least one receiving portion other than the entrance; as well as An open / close section, configured to adjust the opening and closing of the inlet. The components forming the at least one receiving portion, the wall, and the opening / closing portion include at least one of molybdenum, tungsten, or zirconium.

2. The framework of claim 1, further comprising a path in internal fluid communication with the at least one receiving portion to generate gas flow.

3. The framework according to claim 2, wherein, The wall includes at least one outlet in fluid communication with the path.

4. The framework according to claim 3, wherein, The diameter of the at least one outlet is 3 mm to 10 mm.

5. The framework according to claim 2, wherein, When the inlet is closed by the open / close portion to perform heat treatment, a predetermined gap exists between the open / close portion and the wall, allowing gas in the at least one receiving portion to be discharged through the predetermined gap.

6. The framework according to claim 2, wherein, The path is in fluid communication with the predetermined gap between the inlet and the open / closed section.

7. The framework according to claim 1, in, The at least one receiving portion includes multiple receiving portions aligned in one direction and stacked. The space within the plurality of receiving portions is formed by a plurality of receiving members aligned in one direction and walls respectively connected to the side portions of the plurality of receiving members. The plurality of receiving portions have a shape having a predetermined margin compared to the shape of the porous transmission layer, and The height of each receiving section is 0.5 mm to 1.0 mm greater than the thickness of each porous transmission layer.

8. The framework according to claim 1, wherein, The thickness of the wall is 0.5 mm to 2.0 mm.

9. The framework according to claim 1, wherein, The minimum distance between the inner wall of the heat treatment device and the frame is equal to or greater than 70 cm.

10. The framework according to claim 1, wherein, The opening / closing portion is slidably or hingedly connected to the wall.

11. The framework according to claim 1, wherein, The minimum distance between the inner wall of the heat treatment device and the porous transport layer forming sheet disposed in the frame is 100 cm or more but 170 cm or less.

12. A structure for manufacturing a porous transport layer, the structure serving as a support for manufacturing a titanium-based porous transport layer applied in a heat treatment apparatus, the structure comprising: Multiple loading portions are arranged such that the porous transport layer is loaded thereon; A support member that supports the plurality of loading portions to form a predetermined interval between the plurality of loading portions; as well as A capping portion, the capping portion including an internal space formed by opening one surface of the capping portion and configured to open or close the plurality of loading portions spaced apart at predetermined intervals. The plurality of loading portions, the support member, and the cover portion include at least one of molybdenum or tungsten.

13. The structure according to claim 12, wherein, The capping portion includes at least one outlet.

14. The structure according to claim 12, in, The cover portion accommodates the loading portion and the support member via the one surface, and is then closed such that a predetermined gap is arranged between the cover portion and the surface of the heat treatment apparatus that contacts the cover portion.

15. The structure according to claim 14, wherein, The predetermined gap is 2mm to 10mm.

16. The structure according to claim 12, wherein, The minimum distance between the inner wall of the heat treatment device and the structure is equal to or greater than 70 cm.

17. The structure according to claim 12, wherein, The minimum distance between the inner wall of the heat treatment device and the porous transport layer forming sheet arranged in the structure is 100 cm or more but 170 cm or less.

18. The structure according to claim 12, wherein, The thickness of the cap portion is 0.5 mm to 2.0 mm.

19. A heat treatment apparatus for manufacturing a porous transport layer comprising the framework of claim 1.

Images