JP2009211928A - Carbon fiber paper and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a carbon fiber paper for a solid polymer electrolyte fuel cell gas diffusion layer having properties excellent in mass transfer and heat transfer. <P>SOLUTION: The carbon fiber paper 12 includes a plurality of pores whose average hole diameter formed in a gap of each fiber is 10 to 20 μm and non-through-holes 18 whose average hole diameter formed in concave from one face to another face is 50 to 500 μm. The depth of the non-through-holes 18 is 20 to 80% of the thickness of the carbon fiber paper 12, the number of the non-through-holes 18 per a unit area is 100 to 1,000/cm<SP>2</SP>and the thickness is 50 to 400 μm. Preferably, the carbon fiber paper 12 contains fibrous carbon and non-fibrous carbon, the ratio of the fibrous carbon in the carbon fiber paper is 20 mass% or larger, and the thickness is 50 to 400 μm. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention has a large number of fine pores formed by gaps between fibers and a plurality of non-through holes that are larger in diameter than the pores and formed in a concave shape from one surface to the other surface. The present invention relates to a carbon fiber paper for a solid polymer electrolyte fuel cell gas diffusion layer and a method for producing the same.

  Carbon fiber paper is smaller in thickness and pore diameter than carbon fiber woven fabrics, has less unevenness in air permeability and thickness than carbon fiber nonwoven fabrics, and has excellent properties in mass transfer and heat transfer in the sheet. Utilizing this property, carbon fiber paper is used for a gas diffusion layer electrode substrate for polymer electrolyte fuel cells, a substrate for printed wiring boards, and the like.

  However, when a porous material such as carbon fiber paper is used for the gas diffusion layer, water generated during power generation stays in the gas diffusion layer under the high current density region and high humidification condition. There is a problem that supply is cut off and power generation stops (flooding phenomenon). On the other hand, under a low current density region and a low humidification condition, there is a problem that the electrolyte membrane is dried due to a decrease in the amount of generated water and the battery performance is lowered.

  As a method for solving the above problem, a method of forming a through-hole or a through-groove having a large opening diameter in a gas diffusion layer or a gas diffusion film as compared with a large number of fine pores formed by gaps between fibers Has been proposed (see, for example, Patent Documents 1 to 4). However, in this method, the presence of the through hole or the groove has a low mechanical strength, which is disadvantageous in terms of handleability, increases the contact resistance with the catalyst layer, and further, the through hole or the groove portion. There is a problem that gas permeability is different from other parts, and the electrolyte membrane is partially depleted particularly in a low current density region.

As another method for solving the above problem, a method has been proposed in which a gas diffusion film made of graphite particles is formed on a substrate made of carbon paper or the like, and a recess is formed from the front surface to the back surface of the film ( For example, see Patent Document 5). However, in this method, the gas diffusion film made of graphite particles has poor air permeability, and there is a problem in sufficiently preventing the flooding phenomenon particularly in a high current density region.
JP 2007-103241 A (Claims) JP 2006-331786 A (Claims) Japanese Patent Laying-Open No. 2005-108820 (Claims) JP 2004-152584 A (Claims) JP 2006-4787 A (Claims)

  An object of the present invention is to provide a carbon fiber paper and a method for producing the same that solve the above problems.

  Specifically, in a wide range of battery reactions from high current density range and high humidification conditions to low current density range and low humidification conditions, water management is excellent, and the gas diffusivity is uniform without hindering the battery reaction. It is an object of the present invention to provide a carbon fiber paper for a solid polymer electrolyte fuel cell gas diffusion layer in which an increase in contact resistance with a catalyst layer is suppressed and a method for producing the same.

  In order to achieve the above object, as a result of intensive studies by the present inventors, carbon fiber paper having relatively small pores with respect to the carbon fiber fabric has a predetermined depth from one surface to the other surface. It has been found that carbon fiber paper having a plurality of non-through holes having a larger pore diameter than the pores of carbon fiber paper is optimal as a solid polymer electrolyte type gas diffusion layer.

  That is, the present invention that achieves the above object is as described below.

[1] A pore having an average pore diameter of 10 to 20 μm formed by a gap between fibers and a non-through hole having an average pore diameter of 50 to 500 μm formed in a concave shape from one surface to the other surface. A plurality of carbon fiber papers, wherein the depth of the non-through holes is 20 to 80% of the thickness of the carbon fiber paper, the number of non-through holes per unit area is 100 to 1000 / cm ² , and the thickness Carbon fiber paper for solid polymer electrolyte fuel cell gas diffusion layers having a thickness of 50 to 400 μm.

  [2] The carbon fiber paper according to [1], wherein the carbon fiber paper contains fibrous carbon and non-fibrous carbon, and the ratio of the fibrous carbon in the carbon fiber paper is 20% by mass or more.

[3] Oxidized fiber paper is subjected to aperture processing by laser processing to obtain an oxidized fiber paper having a plurality of non-through holes formed in a concave shape from one surface to the other surface, and then the oxidized fiber paper Is fired at a temperature of 1300 to 2500 ° C. in an inert atmosphere, and pores having an average pore diameter of 10 to 20 μm formed between the fibers and from one surface to the other surface A carbon fiber paper having a plurality of non-through holes with an average hole diameter of 50 to 500 μm formed in a concave shape, wherein the depth of the non-through holes is 20 to 80% of the thickness of the carbon fiber paper, and per unit area A method for producing carbon fiber paper for a solid polymer electrolyte fuel cell gas diffusion layer, wherein the number of non-through holes is 100 to 1000 / cm ² and the thickness is 50 to 400 μm.

[4] Oxidized fiber paper is subjected to an aperture treatment by laser processing to obtain an oxidized fiber paper having a plurality of through holes extending from one surface to the other surface, and the oxidized fiber paper subjected to the aperture treatment; Affixed oxidized fiber paper having a plurality of non-through holes formed in a concave shape from one surface to the other surface is obtained by pasting the untreated oxidized fiber paper, and then the pasted oxidized fiber Paper is fired in an inert atmosphere at a temperature of 1300 to 2500 ° C., and has an average pore diameter of 10 to 20 μm formed between the fibers and from one side to the other side. Carbon fiber paper having a plurality of non-through holes with an average hole diameter of 50 to 500 μm formed in a concave shape, and the depth of the non-through holes is 20 to 80% of the thickness of the carbon fiber paper, and the unit area The number of non-through holes per 100 to 1 00 pieces / cm ^2, a solid polymer electrolyte fuel cell manufacturing method of the carbon fiber paper for gas diffusion layer is a thickness of 50 to 400 [mu] m.

  When the carbon fiber paper of the present invention is used as a gas diffusion layer in a solid polymer electrolyte fuel cell, one surface of the gas diffusion layer that is opened in a concave shape is disposed on the separator side, and the other surface is The gas diffusion layer exhibits excellent water management capability under a wide range of battery reaction conditions, from high current density and high humidification conditions to low current density and low humidification conditions, by placing it on the catalyst layer side. To do.

  That is, under the high current density region and high humidification condition of one battery reaction condition, the generated water is quickly discharged from the recess formed in the gas diffusion layer, thereby preventing the battery reaction from being lowered due to flooding. On the other hand, when the carbon fiber paper having a through hole is used as a gas diffusion layer under a battery reaction condition in a low current density region and a low humidification condition, partial depletion of the electrolyte membrane due to local concentration of supply gas through the through hole Occurs, and the contact resistance with the catalyst layer also increases.

  On the other hand, when the carbon fiber paper of the present invention is used as a gas diffusion layer, the hole formed in a concave shape is a non-through hole, and therefore, even under battery reaction conditions in a low current density region and a low humidification condition, In addition, it is possible to suppress partial depletion of the catalyst, and to suppress an increase in contact resistance with the catalyst layer.

  Hereinafter, the present invention will be described in detail.

  FIG. 1 is a conceptual diagram showing an example in which the carbon fiber paper of the present invention is incorporated into a solid polymer electrolyte fuel cell, and is a cross-sectional view along a vertical plane extending from one surface of the carbon fiber paper to the other surface. It is.

  As shown in FIG. 1, a solid polymer electrolyte fuel cell 2 includes an electrolyte membrane 4, a pair of electrodes composed of catalyst layers 6 and 8, a pair of gas diffusion layers composed of carbon fiber paper 10 and 12, and a pair of With the separators 14 and 16 as main constituent members, one cell is formed of these members.

  The electrolyte membrane 4 has proton conductivity, and a pair of electrodes including catalyst layers 6 and 8 containing a noble metal are arranged on the outside thereof, one of the catalyst layers 6 serving as an anode and the other catalyst layer 8 serving as a cathode. Become. A pair of gas diffusion layers made of carbon fiber papers 10 and 12 are arranged outside the electrodes made of the catalyst layers 6 and 8.

  The gas diffusion layer 10 permeates and diffuses hydrogen gas, methanol, or the like as fuel. The gas diffusion layer 12 serves to drain water generated by combustion of fuel and collect and conduct electrons generated at the electrodes. Furthermore, separators 14 and 16 are provided on the outer surfaces of the gas diffusion layers 10 and 12, and flow paths (not shown) such as fuel and combustion products are provided on the surfaces in contact with the gas diffusion layers 10 and 12.

  In the solid polymer electrolyte fuel cell 2, hydrogen is supplied to the anode formed of the catalyst layer 6, and protons are generated by the catalyst. The protons pass through the electrolyte membrane 4 and reach the cathode made of the catalyst layer 8, and combine with electrons to generate water. The proton conductivity of the electrolyte membrane 4 changes depending on the moisture in the membrane 4, and the conductivity increases when the amount of moisture is large, and decreases when the amount of moisture is small.

  In the solid polymer electrolyte fuel cell 2, moisture management is extremely important, and it is necessary to achieve both water drainage at the cathode formed of the catalyst layer 8 and water retention of the electrolyte membrane 4.

  The carbon fiber paper of the present invention has an average pore diameter of 10 to 20 μm formed in the gap between the fibers, and an average pore diameter of 50 to 500 μm formed in a concave shape from one surface to the other surface, Preferably, the carbon fiber paper has a plurality of non-through holes 18 of 90 to 250 μm, and the depth of the non-through holes 18 is 20 to 80% of the thickness of the carbon fiber paper. When used for the gas diffusion layer 12 on the cathode side, both the drainage of water at the cathode formed of the catalyst layer 8 and the water retention of the electrolyte membrane 4 can be achieved.

  When the depth of the non-through hole 18 is less than 20% of the thickness of the carbon fiber paper, the mass mobility in the carbon fiber paper is lowered. For example, the carbon fiber paper is used as a gas diffusion layer electrode base material for a polymer electrolyte fuel cell. When used in the above, the reaction product water cannot be smoothly discharged from the non-through holes, and the reaction product water is likely to be flooded to shut off the supply of the fuel gas.

  When the depth of the non-through hole 18 exceeds 80% of the thickness of the carbon fiber paper, unevenness occurs in the mass mobility in the carbon fiber paper, and the carbon fiber paper is used as a gas diffusion layer electrode group for a polymer electrolyte fuel cell. When used as a material, it is difficult to supply a uniform gas, which causes local depletion of the electrolyte membrane and is liable to reduce the power generation performance of the fuel cell. Furthermore, the strength of the carbon fiber paper itself is reduced.

The number of non-through holes is preferably 100 to 1000 / cm ² per unit area, and more preferably 300 to 500 pieces / cm ^2.

  The carbon fiber paper of the present invention contains fibrous carbon and non-fibrous carbon. When carbon fiber paper is used for the gas diffusion layer electrode substrate for polymer electrolyte fuel cells, the ratio of fibrous carbon in the carbon fiber paper is preferably 20% by mass or more in order to increase strength and conductivity. The thickness of the carbon fiber paper is preferably 50 to 400 μm.

  Fibrous carbon is derived from oxidized fibers in raw oxidized fiber paper, and non-fibrous carbon is derived from organic polymers mixed with oxidized fibers when obtaining raw oxidized fiber paper by wet papermaking. is there. That is, in the carbonization treatment described later, the oxidized fiber becomes fibrous carbon, and the organic polymer becomes non-fibrous carbon.

  As a method for producing the carbon fiber paper of the present invention, for example, raw material oxidized fiber paper is subjected to an opening treatment by laser processing to obtain an oxidized fiber paper having a plurality of non-through holes extending from one surface to the other surface, It is preferable to produce the oxidized fiber paper by baking and carbonizing at 1300 to 2500 ° C. in an inert atmosphere.

  Alternatively, the oxidized fiber paper is subjected to an aperture treatment by laser processing to obtain an oxidized fiber paper having a plurality of through holes extending from one surface to the other surface, and the oxidized fiber paper subjected to the aperture treatment and the aperture treatment. There is a method in which the affixed oxidized fiber paper is carbonized under the above-mentioned conditions after affixed to the oxidized fiber paper not subjected to.

[Raw material oxidized fiber paper]
The raw material oxidized fiber paper for producing the carbon fiber paper of this example can be obtained by mixing an oxidized fiber having a predetermined fiber length and an organic polymer and using an existing wet papermaking method. Oxidized fibers such as polyacrylonitrile (PAN), pitch-based, phenol-based, rayon-based oxidized fibers can be used as the oxidized fibers, but PAN-based oxidized fibers are preferred from the strength characteristics of the oxidized fibers and the obtained carbon fibers. . As the organic polymer, aromatic polyamide (aramid), phenol resin, polyimide, PAN, etc. are suitable because of the high residual carbon ratio after carbonization, liquid, powder, pellet, short fiber, pulp, etc. Available in the form of

[Heat compression treatment]
The above-mentioned raw oxidized fiber paper is preferably subjected to a heat compression treatment at a temperature of 100 to 350 ° C. and a pressure of 0.30 to 20 MPa for the purpose of homogenization and high bulk density. The bulk density of the raw oxidized fiber paper is controlled to 1.0 to 0.2 g / cm ³ .

  Homogenization by heat compression treatment can be performed, for example, by calendaring or pressing.

  As a result of this heat compression treatment, the oxidized fibers are compressed, and the pore diameter formed by the gap between the oxidized fibers is controlled by the compression.

  In the present invention, laser processing, which will be described later, is performed using the raw material oxidized fiber paper whose pore diameter is controlled in this way.

[Opening treatment]
The raw material oxidized fiber paper is subjected to a hole opening process with a laser processing apparatus to obtain oxidized fiber paper having a diameter of 54 to 540 μm and non-through holes of 100 to 10,000 pieces / cm ² . As the type of the laser processing apparatus, YAG, CO ₂ , a semiconductor laser, or the like can be used.

  As described above, by carrying out laser processing of oxidized fiber paper, it has a plurality of non-through holes with an average hole diameter of 50 to 500 μm formed in a concave shape from one surface to the other surface. Oxidized fiber paper having a depth of 20 to 80% of the thickness of the carbon fiber paper can be easily obtained.

  As the laser processing conditions, for example, laser irradiation conditions in a conventionally known carbon dioxide laser can be appropriately employed. In the carbon dioxide laser, a wavelength of 9.3 to 10.6 μm in the infrared wavelength region is generally used, and energy of 4 to 60 mJ is preferably used.

  As described above, through-holes may be formed in oxidized fiber paper to obtain porous oxidized fiber paper, and non-porous oxidized fiber paper may be bonded thereto.

[Carbonization treatment]
The oxidized fiber paper is baked and carbonized at 1300 to 2500 ° C. through a step of pre-baking near 500 ° C. in an inert gas atmosphere such as nitrogen to obtain carbon fiber paper.

  In addition, the temperature increase rate in the case of carbonization under temperature increase is preferably 200 ° C./min or less.

  The carbon fiber paper obtained by the above production method has a plurality of non-through holes with an average hole diameter of 50 to 500 μm formed in a concave shape from one surface to the other surface, and the depth of the non-through holes. Is 20 to 80% of the thickness of the carbon fiber paper.

  Moreover, this carbon fiber paper has an average pore diameter of 10 to 20 μm, an air permeability of 10,000 ml / min or more, and a bending strength is 10 MPa or more without forming a film-like carbide on the surface.

Further, the carbon fiber paper has a thickness of 50 to 400 μm, a basis weight of 20 to 180 g / m ² , and a bulk density of 0.2 to 0.6 g / cm ³ .

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. In addition, evaluation of operation conditions and measurement of each physical property were based on the following methods.

[Pore diameter of oxidized fiber paper and carbon fiber paper]
Using a palm porometer [PMI (Porous Material, Inc.): trade name CFP-1100AEX], the pore distribution of oxidized fiber paper and carbon fiber paper is measured, and the volume average pore diameter is obtained from the pore distribution. It was.

[Non-through holes in oxidized fiber paper and carbon fiber paper]
Using a digital microscope (manufactured by KEYENCE, trade name: VH-8000C), various dimensions of non-through holes of oxidized fiber paper and carbon fiber paper were measured, and the average non-penetration was determined from these measured values by the above-described calculation method. The hole diameter, non-through hole density, non-through hole roundness, and non-through hole front / back diameter ratio were determined.

[Specific gravity of oxidized fiber]
It was measured by the Archimedes method (solvent acetone).

[Thickness of oxidized fiber paper and carbon fiber paper]
The thickness when a load of 1.2 N was applied with a disk-shaped pressure plate having a diameter of 5 mm was measured.

[Oxidized fiber paper, carbon fiber paper weight]
The mass per unit area was calculated from the mass obtained by drying a 100 mm square sheet at 120 ° C. for 1 hour.

[Bulk density of oxidized fiber paper and carbon fiber paper]
It was calculated from the thickness and basis weight measured under the above conditions.

[Example 1]
Polyacrylonitrile (PAN) -based oxidized fiber (average fiber thickness 2.2 dtex, average fiber length 5 mm, specific gravity 1.42) as oxidized fiber, aramid fibrid (average fiber length 1.2 mm) as organic polymer, PET Fibers (average fiber thickness 2.5 dtex, average fiber length 5 mm) were mixed so that the blending ratio was 65/15/20% by mass, and wet papermaking was performed to obtain raw material oxidized fiber paper. This raw oxidized fiber paper is compressed at a temperature of 120 ° C. and a pressure of 0.5 MPa to form a basis weight of 147 g / m ² , a thickness of 320 μm, a bulk density of 0.46 g / cm ³ , and a gap between fibers. An oxidized fiber paper having an average pore diameter of 17 μm was obtained.

This oxidation fiber paper, subjected to a pore-opening treatment by laser processing apparatus, the diameter 220 .mu.m, depth 240 .mu.m (0.75% of oxidized fiber sheet thickness), the oxide fiber paper having a non-through holes of 320 / cm ² Obtained. Subsequently, the oxidized fiber paper is baked in a nitrogen gas atmosphere at 500 ° C. for 10 minutes and at 2000 ° C. for 10 minutes, whereby carbon having a basis weight of 75 g / m ² , a thickness of 200 μm and a bulk density of 0.375 g / cm ³ is obtained. A fiber paper was obtained.

[Example 2]
Carbon fiber paper was obtained in the same manner as in Example 1 except that the depth of the non-through holes in the oxidized fiber paper was 80 μm (25% of the thickness of the oxidized fiber paper). The paper has a non-through hole diameter of 202 μm, a non-through hole depth of 50 μm (25% of the thickness of the carbon fiber paper), a non-through hole surface density of 400 pieces / cm ² , and a gap between fibers. The average pore diameter of the fine pores was 15 μm.

Example 3
An oxidized fiber paper having a basis weight of 72 g / m ² , a thickness of 160 μm, a bulk density of 0.45 g / cm ³ , and an average pore diameter of 17 μm formed by gaps between fibers is subjected to a hole opening treatment with a laser processing apparatus, and the diameter A porous oxidized fiber paper having through-holes of 220 μm and 320 pieces / cm ² was obtained. Subsequently, nonporous oxidized fiber paper having a basis weight of 72 g / m ² , a thickness of 160 μm, a bulk density of 0.45 g / cm ³ , and an average pore diameter of 17 μm of pores formed between the fibers is applied to the porous oxidized fiber paper. A laminated oxidized fiber paper (sticky oxidized fiber paper) was obtained. By carbonizing and firing this sticky-type oxidized fiber paper in the same manner as in Example 1, carbon fiber paper having a basis weight of 75 g / m ² , a thickness of 200 μm, and a bulk density of 0.375 g / cm ³ was obtained.

As shown in Table 1, the obtained carbon fiber paper has a non-through hole diameter of 202 μm, a non-through hole depth of 100 μm (50% of the thickness of the carbon fiber paper), and a non-through hole surface density of 400 μm. Pieces / cm ² , and the average pore diameter of the pores formed by the gaps between the fibers was 15 μm.

[Comparative Example 1]
A carbon fiber paper was obtained in the same manner as in Example 1 except that the oxidized fiber paper was not subjected to opening treatment. The carbon fiber paper had no relatively large holes with a diameter of 50 μm or more and was formed in the gap between the fibers. The average pore diameter of the pores formed was 15 μm.

[Comparative Example 2]
As shown in Table 1, carbon fiber paper was obtained in the same manner as in Example 1 except that the depth of the non-through hole in the oxidized fiber paper was 40 μm (12.5% of the thickness of the oxidized fiber paper). The carbon fiber paper has a non-through hole diameter of 202 μm, a non-through hole depth of 25 μm (12.5% of the thickness of the carbon fiber paper), a non-through hole surface density of 400 / cm ² , The average pore diameter of the pores formed by the gaps was 15 μm.

[Comparative Example 3]
As shown in Table 1, carbon fiber paper was obtained in the same manner as in Example 1 except that the depth of the non-through hole in the oxidized fiber paper was 280 μm (87.5% of the thickness of the oxidized fiber paper). The carbon fiber paper has a non-through hole diameter of 202 μm, a non-through hole depth of 175 μm (87.5% of the thickness of the carbon fiber paper), a non-through hole surface density of 400 / cm ² , The average pore diameter of the pores formed by the gaps was 15 μm.

[Comparative Example 4]
A carbon fiber paper was obtained in the same manner as in Example 1 except that the holes were penetrated in the opening process of the oxidized fiber paper. As shown in Table 1, the carbon fiber paper had a through-hole diameter of 202 μm and a through-hole. The depth was 202 μm (100% of the thickness of the carbon fiber paper), the surface density of the through holes was 400 / cm ² , and the average pore diameter of the pores formed by the gaps between the fibers was 15 μm.

[Evaluation example]
Using the carbon fiber paper obtained in Examples 1 to 3, a gas diffusion layer electrode base material for a solid polymer electrolyte fuel cell was prepared, and an evaluation test as an electrode base material was performed under the high humidification conditions shown in Table 2. Below, it carried out on the low humidification conditions. As a result, for any of the carbon fiber papers obtained in Examples 1 to 3, as shown in FIGS. 2 to 3, a voltage drop was observed up to a high current density under both high and low humidification conditions. However, high battery performance can be maintained in a wide current density range.

As a result of performing the same evaluation test using the carbon fiber paper obtained in Comparative Examples 1 and 2, a voltage drop was observed at a low current density under high humidification conditions for any of the carbon fiber papers. The performance was low.
The reaction product water was not sufficiently discharged, and satisfactory results were not obtained as electrode equipment.

  As a result of performing the same evaluation test using the carbon fiber paper obtained in Comparative Examples 3 to 4, a voltage drop was observed at a low current density under low humidification conditions for any carbon fiber paper, and the battery The performance was low.

It is a conceptual diagram which shows an example which incorporated the carbon fiber paper of this invention in the solid polymer electrolyte fuel cell, Comprising: It is sectional drawing along the perpendicular | vertical surface ranging from one surface of carbon fiber paper to the other surface. It is the graph which showed the change of the voltage with respect to the current density of the solid polymer electrolyte type fuel cell in the highly humidified condition about Examples 1-3 and Comparative Examples 1-4. It is the graph which showed the change of the voltage with respect to the current density of the polymer electrolyte fuel cell in low humidification conditions about Examples 1-3 and Comparative Examples 1-4.

Explanation of symbols

2 Solid Polymer Electrolyte Fuel Cell 4 Electrolyte Membrane 6, 8 Catalyst Layer 10, 12 Carbon Fiber Paper 14, 16 Separator 18 Non-Through Hole

Claims (4)

Carbon having a plurality of pores having an average pore diameter of 10 to 20 μm formed by gaps between fibers and non-through holes having an average pore diameter of 50 to 500 μm formed in a concave shape from one surface to the other surface Fiber paper, wherein the depth of the non-through holes is 20 to 80% of the thickness of the carbon fiber paper, the number of non-through holes per unit area is 100 to 1000 / cm ² , and the thickness is 50 to Carbon fiber paper for a solid polymer electrolyte fuel cell gas diffusion layer having a thickness of 400 μm. The carbon fiber paper according to claim 1, wherein the carbon fiber paper contains fibrous carbon and non-fibrous carbon, and the ratio of the fibrous carbon in the carbon fiber paper is 20% by mass or more. Oxidized fiber paper is subjected to aperture processing by laser processing to obtain oxidized fiber paper having a plurality of non-through holes formed in a concave shape from one surface to the other surface, and then the oxidized fiber paper is inactivated It is fired at a temperature of 1300 to 2500 ° C. in an atmosphere, and is formed with pores having an average pore diameter of 10 to 20 μm formed by the gap between the fibers and concave from one surface to the other surface. Carbon fiber paper having a plurality of non-through holes with an average pore diameter of 50 to 500 μm, wherein the depth of the non-through holes is 20 to 80% of the thickness of the carbon fiber paper, and the non-through holes per unit area The manufacturing method of the carbon fiber paper for solid polymer electrolyte type fuel cell gas diffusion layers whose number of holes is 100-1000 piece / cm < ² >, and whose thickness is 50-400 micrometers. Oxidized fiber paper is subjected to an aperture treatment by laser processing to obtain an oxidized fiber paper having a plurality of through holes extending from one surface to the other surface, and the oxidized fiber paper subjected to the aperture treatment and the aperture treatment are performed. By attaching non-oxidized fiber paper, a sticky-type oxidized fiber paper having a plurality of non-through holes formed in a concave shape from one surface to the other surface is obtained. Baking at a temperature of 1300 to 2500 ° C. in an active atmosphere, pores having an average pore diameter of 10 to 20 μm formed by the gap between the fibers, and concave from one surface to the other surface A carbon fiber paper having a plurality of non-through holes with an average pore diameter of 50 to 500 μm formed, the depth of the non-through holes being 20 to 80% of the thickness of the carbon fiber paper, The number of through holes is 100 to 1000 / Cm < ² >, The manufacturing method of the carbon fiber paper for solid polymer electrolyte type fuel cell gas diffusion layers which is 50-400 micrometers in thickness.

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