JPH06135770A - Carbonaceous preformed body, its production and production of electrode substrate - Google Patents

Abstract

PURPOSE:To improve homogeneity, gas permeability, thermal conductivity, electric conductivity, and mechanical strength and to control the pore diameter and distribution of pores as regards an electrode substrate for a fuel cell. CONSTITUTION:A slurry containing 100 pts.wt. of carbon fiber and/or fiber which can be changed into carbon fiber, 20-200 pts.wt. of binder having 40-75wt.% carbonization yield, 10-500 pts.wt. of org. granular material having <=30wt.% carbonzation yield, and 10-250 pts.wt. of mesophase pitch having >=70wt.% carbonization yield is molded by sucking to form a carbonaceous preformed body having a paper structure. As for the org. granular material, a hardened material of thermosetting resin which does not soften by heat, or a hardened material of thermosetting resin containing pitch is used. The preformed body having a paper structure is homogeneous without precipitation of the org. granular material. The preformed body is molded with heat and pressure, and then carbonized or graphitized to obtain an electrode substrate.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は、リン酸型燃料電池など
の電極板を得る上で有用な炭素質予備成形体とその製造
方法、並びに電極基板の製造方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carbonaceous preform useful for obtaining an electrode plate for a phosphoric acid fuel cell, a method for producing the same, and a method for producing an electrode substrate.

【０００２】[0002]

【従来の技術】燃料電池は、他の発電装置と異なり、Ｓ
Ｏx 、ＮＯx 及び粉塵などの公害物質の発生が極めて少
なく、騒音発生源も少ないなどの特徴を有している。こ
のような燃料電池のうちリン酸型燃料電池は、電解液の
両側にポーラスな陰極と陽極を設けて単位セルを構成
し、各単位セルをセパレータを介して積層した構造を有
する。2. Description of the Related Art A fuel cell, unlike other power generators, has an S
It is characterized by extremely low emission of pollutants such as Ox, NOx and dust, and low noise sources. Among such fuel cells, the phosphoric acid type fuel cell has a structure in which a porous cathode and an anode are provided on both sides of an electrolytic solution to form a unit cell, and each unit cell is laminated via a separator.

【０００３】前記陰極および陽極には、電気エネルギー
への変換効率を高めるため、細孔分布を任意にコントロ
ールでき、ガス透過性が高いことが要求される。さら
に、電気伝導性、機械的強度および作動温度における耐
リン酸液性などに加えて、高い熱伝導性が要求される。In order to enhance the efficiency of conversion into electric energy, the cathode and the anode are required to be able to control the pore distribution arbitrarily and have high gas permeability. Furthermore, high thermal conductivity is required in addition to electrical conductivity, mechanical strength and resistance to phosphoric acid at operating temperature.

【０００４】従来、燃料電池電極板の製造方法として、
フェノール樹脂などの結合剤と、炭素繊維と、粉粒状の
熱可塑性樹脂を特定の割合で乾式混合し、混合物を熱ロ
ールや熱プレスによりシート状に加圧成形し、炭化又は
黒鉛化処理する方法が採用されている（特公平１−３６
６７０号公報）。Conventionally, as a method of manufacturing a fuel cell electrode plate,
A method in which a binder such as a phenol resin, carbon fiber, and a granular thermoplastic resin are dry-mixed in a specific ratio, and the mixture is pressure-molded into a sheet by a hot roll or hot press, and carbonized or graphitized. Has been adopted (Tokuhei 1-36
670).

【０００５】しかし、この方法では、炭素繊維と、結合
剤及び熱可塑性樹脂とが、混合性の悪い繊維状と粉粒状
であるため、乾式混合する際、炭素繊維と結合剤及び熱
可塑性樹脂とが偏析し易く、均質な混合物を得るのが困
難である。また、粉末状混合物の加圧成形により、偏析
した結合剤及び熱可塑性樹脂が凝集し、成形物がさらに
不均質となり易い。さらに、加熱加圧成形により、偏析
した熱可塑性樹脂が軟化するだけでなく、炭化又は黒鉛
化処理する際に、熱可塑性樹脂が再び軟化する。そのた
め、結合剤及び熱可塑性樹脂の偏析と、熱可塑性樹脂の
二度に亘る軟化とにより、電極基板の均質性が低下す
る。そして、この不均質性に起因するためか、結合剤、
炭素繊維、及び粉粒状の熱可塑性樹脂を用いて得られた
電極基板は、曲げ強度、圧縮強度、ガス透過性が部位に
よって変動し、不均質であるだけでなく、熱伝導率も小
さい。However, in this method, since the carbon fiber, the binder and the thermoplastic resin are in a fibrous form or powdery granule having poor mixability, the carbon fiber, the binder and the thermoplastic resin are mixed during the dry mixing. Segregates easily and it is difficult to obtain a homogeneous mixture. Further, when the powder mixture is pressure-molded, the segregated binder and the thermoplastic resin are aggregated, and the molded product is likely to be more inhomogeneous. Further, the heat and pressure molding not only softens the segregated thermoplastic resin, but also softens the thermoplastic resin again during carbonization or graphitization. Therefore, the segregation of the binder and the thermoplastic resin and the softening of the thermoplastic resin for two times reduce the homogeneity of the electrode substrate. And because of this heterogeneity, the binder,
The electrode substrate obtained by using the carbon fibers and the thermoplastic resin in the form of powder or granules is not only inhomogeneous because the bending strength, the compressive strength, and the gas permeability vary depending on the site, and the thermal conductivity is small.

【０００６】また、偏析した結合剤及び熱可塑性樹脂に
起因して、電極基板の細孔径分布が不均一となる。特に
厚みの薄い電極板を得る場合には、均質な細孔を形成さ
せるのが困難である。Further, due to the segregated binder and thermoplastic resin, the pore size distribution of the electrode substrate becomes non-uniform. Especially when obtaining a thin electrode plate, it is difficult to form uniform pores.

【０００７】より具体的には、前記の方法において厚み
が１ｍｍ以上である場合には、大きさが１０００ｍｍ×
１０００ｍｍ程度であっても、電極板の細孔が比較的均
質であるが、厚みが１ｍｍ未満では均質な細孔が形成さ
れない。さらに、炭素繊維の短繊維、結合剤及び粉粒状
の有機物質とを乾式混合した粉末状であるため、加圧成
形時に金型に均一に充填するのが困難であり、作業性が
極めて悪い。More specifically, in the above method, when the thickness is 1 mm or more, the size is 1000 mm ×
Even if the thickness is about 1000 mm, the pores of the electrode plate are relatively homogeneous, but if the thickness is less than 1 mm, the homogeneous pores are not formed. Furthermore, since it is in the form of powder obtained by dry-mixing short fibers of carbon fibers, a binder and a granular organic material, it is difficult to uniformly fill the mold during pressure molding, and the workability is extremely poor.

【０００８】また、上記方法においては、気孔形成剤と
しての熱可塑性樹脂の粒径が細孔径分布に大きく影響す
るものの、前記のように二度に亘って熱可塑性樹脂が軟
化するため、結合剤の偏析と相まって、細孔径が大きく
変化し、細孔径分布が不均一になり易い。その結果、細
孔径分布を任意に精度よくコントロールできず、ガス透
過性、電気伝導性及び機械的強度の優れた電極板を得る
ことができない。Further, in the above method, although the particle size of the thermoplastic resin as the pore-forming agent has a great influence on the pore size distribution, the thermoplastic resin is softened twice as described above, so that the binder is used. Coupled with the segregation of No. 3, the pore size changes greatly, and the pore size distribution tends to become non-uniform. As a result, it is not possible to control the pore size distribution arbitrarily and accurately, and it is not possible to obtain an electrode plate having excellent gas permeability, electrical conductivity and mechanical strength.

【０００９】しかも、混合物を熱ロールや熱プレスによ
りシート状に加熱加圧成形すると、偏析した熱可塑性樹
脂の軟化により、成形板に反りや、膨れが発生しやす
く、特に脱型時にその発生が著しい。更に、この成形板
を焼成により炭化又は黒鉛化処理すると、熱可塑性樹脂
が再び軟化、分解するため、焼成板に反り及び膨れが発
生し易く、均一性、寸法安定性が低下し、最終的に高品
質の電極板の歩留まりが悪い。Moreover, when the mixture is heated and pressed into a sheet by a hot roll or a hot press, the molded plate is liable to warp or swell due to the softening of the segregated thermoplastic resin. Remarkable. Further, when this molded plate is carbonized or graphitized by firing, the thermoplastic resin is softened and decomposed again, so that the fired plate is liable to warp and swell, and uniformity and dimensional stability are lowered, and finally The yield of high quality electrode plates is poor.

【００１０】特開平３−１７４３５９号公報には、炭素
繊維とバインダー粒子とを混合し、抄紙して得られたシ
ート状物を加圧成形した後、炭化又は黒鉛化する方法が
開示されている。しかし、この方法では、気孔率６０〜
８０％を確保するためには、加圧加熱成形時に低圧で成
形する必要がある。一方、低圧で成形すると、繊維同志
の接合強度が低下し、焼成により得られる電極材の曲げ
強度が、１ｋｇｆ／ｍｍ² 以下、圧縮強度が、０．４ｋ
ｇｆ／ｍｍ² 以下に低下し、リン酸型燃料電池用電極材
の要求性能を充足できない。また、電極基板の厚み方向
の体積固有抵抗率も大きく、熱伝導率も小さい。Japanese Unexamined Patent Publication (Kokai) No. 3-174359 discloses a method in which carbon fiber and binder particles are mixed and a sheet-like material obtained by papermaking is pressure-molded and then carbonized or graphitized. . However, with this method, the porosity is 60-
In order to secure 80%, it is necessary to mold at a low pressure during pressure heat molding. On the other hand, when molding at low pressure, the joint strength between fibers decreases, the bending strength of the electrode material obtained by firing is 1 kgf / mm ² or less, and the compression strength is 0.4 k.
It falls below gf / mm ² and the required performance of the phosphoric acid fuel cell electrode material cannot be satisfied. In addition, the volume resistivity of the electrode substrate in the thickness direction is large and the thermal conductivity is small.

【００１１】特開平３−７６８２１号公報には、炭素繊
維製造用の有機繊維とパルプとバインダーとしての有機
高分子物質などを混合し、抄紙した得られたシートを成
形した後、焼成し、電極材を得る方法が開示されてい
る。この方法では、有機繊維を用いるため、繊維として
炭素繊維だけを用いた場合よりも高密度に成形できる。
しかし、焼成時における有機繊維の炭化収率（残炭率）
が１０〜３０％と小さい。そのため、得られた電極材
は、成形体に比べて著しく収縮し、厚み１〜３ｍｍ、大
きさ１ｍ角の電極板を製造しても、割り、反り、捩れな
どが生じ、均一性に乏しい。また、厚み方向の収縮率が
大きいため、ガス透過性、体積抵抗率が電極材の部位に
よって変動し、不均質となる。In Japanese Patent Laid-Open No. 3-76821, an organic fiber for producing carbon fiber, pulp, and an organic polymer substance as a binder are mixed, and a sheet obtained by papermaking is molded and then fired to form an electrode. A method of obtaining lumber is disclosed. In this method, since organic fibers are used, it can be molded at a higher density than when only carbon fibers are used as fibers.
However, the carbonization yield (residual coal rate) of organic fibers during firing
Is as small as 10 to 30%. Therefore, the obtained electrode material contracts remarkably as compared with the molded product, and even if an electrode plate having a thickness of 1 to 3 mm and a size of 1 m square is produced, cracking, warping, twisting, etc. occur, resulting in poor uniformity. Further, since the shrinkage ratio in the thickness direction is large, the gas permeability and the volume resistivity vary depending on the site of the electrode material, resulting in heterogeneity.

【００１２】[0012]

【発明が解決しようとする課題】従って、本発明の目的
は、均質性及び熱伝導性に優れる電極基板を得る上で有
用な炭素質予備成形体とその製造方法を提供することに
ある。Therefore, an object of the present invention is to provide a carbonaceous preform useful for obtaining an electrode substrate having excellent homogeneity and thermal conductivity, and a method for producing the same.

【００１３】また、本発明の他の目的は、細孔径とその
分布を任意に精度よくコントロールでき、ガス透過性、
電気伝導性、機械的強度に優れる電極基板を得る上で有
用な炭素質予備成形体とその製造方法を提供することに
ある。Another object of the present invention is to control the pore size and its distribution arbitrarily and accurately, to improve gas permeability,
It is an object of the present invention to provide a carbonaceous preform useful for obtaining an electrode substrate having excellent electrical conductivity and mechanical strength and a method for producing the same.

【００１４】本発明のさらに他の目的は、前記の如き優
れた特性を有する電極基板を効率よく製造できる方法を
提供することにある。Still another object of the present invention is to provide a method capable of efficiently manufacturing an electrode substrate having the above-mentioned excellent characteristics.

【００１５】[0015]

【発明の構成】前記目的を達成するため、本発明者ら
は、鋭意検討の結果、炭素繊維化可能な繊維及び／又は
炭素繊維、結合剤、有機粒状物質およびメソフェーズピ
ッチを含む抄紙構造の炭素質予備成形体を圧縮成形し、
かつ炭化又は黒鉛化する場合には、有機粒状物質の偏析
を防止でき、均質で、熱伝導性に優れた炭素質基板が得
られることを見いだし、本発明を完成した。In order to achieve the above object, the inventors of the present invention have made earnest studies, and as a result, have made paper-forming carbon containing fibers and / or carbon fibers capable of forming carbon fibers, a binder, organic particulate matter and mesophase pitch. Compression molding a quality preform,
In addition, when carbonizing or graphitizing, it was found that a segregation of organic particulate matter can be prevented, a homogeneous carbonaceous substrate having excellent thermal conductivity can be obtained, and the present invention was completed.

【００１６】すなわち、本発明は、炭素繊維化可能な繊
維及び／又は炭素繊維の短繊維、炭化収率４０〜７５重
量％の結合剤、有機粒状物質、およびメソフェーズピッ
チを含む抄紙構造の炭素質予備成形体を提供する。That is, the present invention provides a carbonaceous material having a papermaking structure containing carbon fiber-forming fibers and / or short fibers of carbon fibers, a binder having a carbonization yield of 40 to 75% by weight, organic particulate matter, and mesophase pitch. A preform is provided.

【００１７】また、本発明の方法では、前記成分を含む
スラリーを吸引成形し、炭素質予備成形体を製造する。In the method of the present invention, a slurry containing the above components is suction-molded to produce a carbonaceous preform.

【００１８】さらに、本発明は、前記炭素質予備成形体
を圧縮成形し、炭化又は黒鉛化する電極基板の製造方法
を提供する。Further, the present invention provides a method for producing an electrode substrate in which the carbonaceous preform is compression-molded and carbonized or graphitized.

【００１９】なお、本明細書において、炭化とは、炭素
化可能な成分を、例えば、４５０〜１５００℃程度の温
度で焼成処理することを言う。黒鉛化とは、例えば、１
５００〜３０００℃程度の温度で焼成することを言い、
黒鉛の結晶構造を有していないときでも黒鉛化の概念に
含める。また、炭化収率とは、炭素化可能な成分を炭化
又は黒鉛化したときの残炭率を言う。In the present specification, carbonization means that a carbonizable component is calcined at a temperature of, for example, about 450 to 1500 ° C. Graphitization means, for example, 1
It means firing at a temperature of about 500 to 3000 ° C.,
It is included in the concept of graphitization even when it does not have the crystal structure of graphite. In addition, the carbonization yield refers to the rate of residual coal when carbonizable components are carbonized or graphitized.

【００２０】炭素繊維とは炭化又は黒鉛化された繊維を
言う。耐炎化処理とは、ピッチ系繊維以外の繊維を、例
えば、酸素存在下、２００〜４５０℃程度の温度で加熱
して表面に耐熱層を形成し、焼成時の溶融を防止する処
理を言う。不融化処理とは、例えば、ピッチ系繊維を、
酸素存在下、２００〜４５０℃程度の温度で加熱して表
面に耐熱層を形成し、焼成時の溶融を防止する処理を言
う。Carbon fiber refers to carbonized or graphitized fiber. The flameproofing treatment is a treatment of heating fibers other than pitch-based fibers at a temperature of about 200 to 450 ° C. in the presence of oxygen to form a heat resistant layer on the surface and preventing melting during firing. The infusibilizing treatment, for example, pitch-based fiber,
In the presence of oxygen, it is a treatment of heating at a temperature of about 200 to 450 ° C. to form a heat resistant layer on the surface and preventing melting during firing.

【００２１】本発明の主たる特徴は、（ａ）炭素質予備
成形体が均質性に優れ、有機粒状物質の偏析を防止する
上で有用な抄紙構造を有する点、（ｂ）抄紙構造の炭素
質予備成形体を用い、電極基板の均質性、ガス透過性、
電気伝導性、機械的強度を高めると共に、細孔径とその
分布をコントロールする点、（ｃ）メソフェーズピッチ
を用いることにより、電極基板の熱伝導性を高める点に
ある。The main characteristics of the present invention are: (a) the carbonaceous preform has excellent homogeneity and has a papermaking structure useful for preventing segregation of organic particulate matter, and (b) carbonaceous material having a papermaking structure. Using a preform, the homogeneity of the electrode substrate, gas permeability,
In addition to improving electrical conductivity and mechanical strength, the pore size and its distribution are controlled, and (c) the mesophase pitch is used to increase the thermal conductivity of the electrode substrate.

【００２２】本発明の炭素質予備成形体において、炭素
繊維化可能な繊維としては、炭素繊維の素材となり得る
種々の繊維、例えば、ポリアクリロニトリル繊維、フェ
ノール樹脂繊維、再生セルロース繊維（例えばレーヨ
ン、ポリノジック繊維など）、セルロース系繊維などの
有機繊維、ピッチ系繊維などが挙げられる。炭素繊維化
可能な繊維は、耐炎化処理又は不融化処理されていても
よい。炭素繊維化可能な繊維は、一種又は二種以上使用
できる。In the carbonaceous preform of the present invention, the fibers that can be made into carbon fibers include various fibers that can be used as raw materials for carbon fibers, such as polyacrylonitrile fiber, phenol resin fiber, regenerated cellulose fiber (eg rayon, polynosic). Fibers, etc.), organic fibers such as cellulose fibers, pitch fibers and the like. The carbon fiber-formable fiber may be subjected to a flameproofing treatment or an infusibilization treatment. Fibers that can be made into carbon fibers can be used alone or in combination of two or more.

【００２３】炭素繊維化可能な繊維の繊維直径は、例え
ば、１０〜５０μｍ、好ましくは１５〜４５μｍ程度で
ある。繊維径が１０μｍ未満であると、ガス透過性が低
下し易く、５０μｍを越えると、電極基板の気孔径が大
きくなり、リン酸などの電解液が気孔を塞ぎ、ガス透過
性が低下し易い。The fiber diameter of the carbon fiber can be, for example, about 10 to 50 μm, preferably about 15 to 45 μm. If the fiber diameter is less than 10 μm, the gas permeability tends to decrease, and if it exceeds 50 μm, the pore size of the electrode substrate becomes large, and the electrolyte solution such as phosphoric acid clogs the pores, so that the gas permeability tends to decrease.

【００２４】なお、炭素繊維化可能な繊維の残炭率は、
例えば、１０〜５０％程度である。そのため、炭化又は
黒鉛化に伴なって、上記繊維が、補強材として機能する
炭素繊維となると共に、例えば３０〜７０％程度の体積
収縮に伴なって、炭化又は黒鉛化した結合剤のマトリッ
クス内に間隙が生成し、ガス透過性が向上する。The rate of carbon residue of the carbonizable fiber is
For example, it is about 10 to 50%. Therefore, the carbon fiber functions as a reinforcing material along with the carbonization or graphitization, and in the matrix of the binder carbonized or graphitized with the volume shrinkage of, for example, about 30 to 70%. A gap is generated in the gap and the gas permeability is improved.

【００２５】炭素繊維としては、前記炭素繊維化可能な
繊維を炭化又は黒鉛化した繊維が挙げられる。炭素繊維
も、一種又は二種以上使用できる。炭素繊維の繊維径
は、例えば、５〜３０μｍ、好ましくは１０〜２５μｍ
程度である。繊維径が５μｍ未満であるとガス透過性が
低下し易く、３０μｍを越えると電極基板の気孔径が大
きくなり易い。なお、電極基板における平均気孔径は、
例えば、１０〜４０μｍ程度であるのが好ましい。Examples of the carbon fibers include fibers obtained by carbonizing or graphitizing the above-mentioned carbon fiber-forming fibers. Carbon fibers can also be used alone or in combination of two or more. The fiber diameter of the carbon fiber is, for example, 5 to 30 μm, preferably 10 to 25 μm.
It is a degree. If the fiber diameter is less than 5 μm, the gas permeability tends to decrease, and if it exceeds 30 μm, the pore diameter of the electrode substrate tends to increase. The average pore diameter in the electrode substrate is
For example, it is preferably about 10 to 40 μm.

【００２６】前記炭素繊維は、電極基板の曲げ強度、圧
縮強度を向上させる補強材として機能すると共に、炭化
又は黒鉛化に伴なって電極基板が面方向に収縮するのを
抑制する。The carbon fiber functions as a reinforcing material for improving the bending strength and compressive strength of the electrode substrate, and suppresses the electrode substrate from shrinking in the surface direction due to carbonization or graphitization.

【００２７】炭素繊維化可能な繊維および炭素繊維とし
ては、通常、短繊維が用いられる。短繊維の繊維長は、
例えば０．０５ｍｍ〜１０ｍｍ、好ましくは０．５ｍｍ
〜３ｍｍ程度である。炭素繊維の繊維長は、電極基板の
曲げ強度、電気伝導性や熱伝導度に大きく寄与する。繊
維長が１０ｍｍを越えると細孔径分布をコントロールし
にくくなり、０．０５ｍｍ未満では強度などが低下し易
い。Short fibers are usually used as carbon fibers and carbon fibers. The fiber length of short fibers is
For example, 0.05 mm to 10 mm, preferably 0.5 mm
It is about 3 mm. The fiber length of the carbon fiber greatly contributes to the bending strength, electric conductivity and thermal conductivity of the electrode substrate. When the fiber length exceeds 10 mm, it becomes difficult to control the pore size distribution, and when the fiber length is less than 0.05 mm, the strength and the like are likely to decrease.

【００２８】炭素繊維化可能な繊維と炭素繊維とは単独
で用いてもよいが、少なくとも炭素繊維を含むのが好ま
しい。また、炭素繊維化可能な繊維と炭素繊維とを併用
すると、ガス透過性および強度が向上する。炭素繊維化
可能な繊維と炭素繊維との割合は、電極基板の強度や導
電性などに応じて選択でき、例えば、炭素繊維化可能な
繊維／炭素繊維＝１０〜９０／９０〜１０（重量％）、
好ましくは２５〜７５／７５〜２５（重量％）、さらに
好ましくは３０〜７０／７０〜３０（重量％）程度であ
る。炭素繊維の割合が１０重量％未満では、電極基板の
機械的強度が低下すると共に、収縮が大きくなる傾向を
示し、９０重量％を越えると、ガス透過性が低下し易
い。Although the carbon fiber-forming fiber and the carbon fiber may be used alone, it is preferable to contain at least the carbon fiber. In addition, the combined use of carbon fiber and carbon fiber improves gas permeability and strength. The ratio of carbon fiber convertible fiber to carbon fiber can be selected according to the strength and conductivity of the electrode substrate. For example, carbon fiber convertible fiber / carbon fiber = 10 to 90/90 to 10 (% by weight). ),
It is preferably 25 to 75/75 to 25 (% by weight), and more preferably about 30 to 70/70 to 30 (% by weight). If the proportion of carbon fibers is less than 10% by weight, the mechanical strength of the electrode substrate tends to decrease and the shrinkage tends to increase. If it exceeds 90% by weight, the gas permeability tends to decrease.

【００２９】結合剤としては、例えば、フェノール樹
脂、フラン樹脂、コプナ樹脂などの熱硬化性樹脂；ポリ
アクリロニトリルなどの熱可塑性樹脂；石炭又は石油ピ
ッチなどが使用できる。これらの結合剤のうち、熱硬化
性樹脂、特にフェノール樹脂が好ましい。結合剤の炭化
収率は、電極基板の機械的強度の低下を防止し、気孔率
を調整するため、４０〜７５重量％、好ましくは５０〜
７５重量％程度である。なお、前記フェノール樹脂の炭
化収率は、通常６５〜７５重量％程度と大きい。これら
の結合剤は少なくとも一種使用できる。As the binder, for example, a thermosetting resin such as a phenol resin, a furan resin or a copuna resin; a thermoplastic resin such as polyacrylonitrile; coal or petroleum pitch can be used. Of these binders, thermosetting resins, especially phenolic resins, are preferred. The carbonization yield of the binder is 40 to 75% by weight, preferably 50 to 75% by weight in order to prevent deterioration of mechanical strength of the electrode substrate and adjust porosity.
It is about 75% by weight. The carbonization yield of the phenol resin is usually as large as about 65 to 75% by weight. At least one of these binders can be used.

【００３０】結合剤の割合は、電極基板の強度などに応
じて適当に選択でき、例えば、前記炭素繊維化可能な繊
維および炭素繊維で構成された繊維１００重量部に対し
て、２０〜２００重量部、好ましくは２５〜１５０重量
部程度である。結合剤の割合が２０重量部未満である
と、電極基板の機械的強度が低下し易く、２００重量部
を越えると気孔率が小さくなり、細孔径分布もブロード
になり易く、ガス透過性が低下し易い。The proportion of the binder can be appropriately selected according to the strength of the electrode substrate and the like. For example, 20 to 200 parts by weight relative to 100 parts by weight of the carbon fiber and the fiber composed of carbon fiber. Parts, preferably about 25 to 150 parts by weight. If the proportion of the binder is less than 20 parts by weight, the mechanical strength of the electrode substrate tends to decrease, and if it exceeds 200 parts by weight, the porosity tends to be small, the pore size distribution tends to be broad, and the gas permeability is deteriorated. Easy to do.

【００３１】本発明の炭素質予備成形体は、有機粒状物
質を含んでいる。有機粒状物質としては、例えば、炭化
収率３０重量％以下の有機粒状物質を用いてもよい。炭
化収率が３０％を越えると、微細で均一な気孔の形成や
気孔率の調整が困難である場合が多い。なお、有機粒状
物質の軟化点は、１００℃以上であるのが好ましく、前
記メソフェーズピッチよりも約２５〜１００℃低い場合
が多い。The carbonaceous preform of the present invention contains an organic particulate material. As the organic particulate matter, for example, an organic particulate matter having a carbonization yield of 30% by weight or less may be used. If the carbonization yield exceeds 30%, it is often difficult to form fine and uniform pores or adjust the porosity. The softening point of the organic particulate matter is preferably 100 ° C. or higher, and is often about 25 to 100 ° C. lower than the mesophase pitch.

【００３２】このような有機粒状物質としては、例え
ば、フェノール樹脂、エポキシ樹脂、不飽和ポリエステ
ル樹脂、メラミン樹脂、ジアリルフタレート樹脂、ユリ
ア樹脂及びポリウレタンなどの熱硬化性樹脂の粉粒体
や、熱硬化性樹脂の硬化物からなる粉粒体；ポリ酢酸ビ
ニル、エチレン−酢酸ビニル共重合体、ポリビニルアル
コール、ポリ塩化ビニル、アクリル系ポリマー、ポリエ
ステル、ナイロン、ポリスチレン、スチレン−ブタジエ
ン共重合体、アクリロニトリル−ブタジエン−スチレン
共重合体、スチレン−アクリル共重合体などのスチレン
系ポリマー、ポリカーボネート、ポリアセタールなどの
合成樹脂、ロジンなどの天然物とその誘導体などの熱可
塑性樹脂の粉粒体等が挙げられる。Examples of such organic particulate matter include powdery particles of thermosetting resins such as phenol resin, epoxy resin, unsaturated polyester resin, melamine resin, diallyl phthalate resin, urea resin and polyurethane, and thermosetting. Granules composed of a cured product of a hydrophilic resin; polyvinyl acetate, ethylene-vinyl acetate copolymer, polyvinyl alcohol, polyvinyl chloride, acrylic polymer, polyester, nylon, polystyrene, styrene-butadiene copolymer, acrylonitrile-butadiene -Styrene copolymers such as styrene copolymers and styrene-acrylic copolymers, synthetic resins such as polycarbonate and polyacetal, and powders of thermoplastic resins such as natural products such as rosin and their derivatives.

【００３３】なお、前記熱硬化性樹脂のうち、フェノー
ル樹脂としては、前記結合剤と異なり、炭化収率３０％
以下のものが使用される。これらの有機粒状物質は一種
又は二種以上混合して使用できる。Among the thermosetting resins, the phenol resin is different from the binder in the carbonization yield of 30%.
The following are used: These organic particulate materials may be used alone or in combination of two or more.

【００３４】これらの有機粒状物質は、炭素材に細孔を
生成させる気孔形成剤として機能する。有機粒状物質
は、熱硬化性樹脂の硬化物からなる粉粒体であるのが好
ましい。熱硬化性樹脂の硬化物からなる粉粒体を用いる
と、気孔率及び細孔径を精度よくコントロールできる。
すなわち、熱硬化性樹脂の硬化物からなる粉粒体は加熱
により軟化しないため、硬化物の粒径とその量に対応す
る細孔径の気孔が形成される。そのため、細孔径とその
分布を任意にコントロールでき、シャープ又はブロード
な細孔径分布を有する電極板が得られる。また、同様な
理由から、均質で、ガス透過性、電気伝導度及び機械強
度の優れた電極板を得ることができる。These organic particulate materials function as a pore-forming agent that creates pores in the carbon material. The organic particulate matter is preferably a powder or granular material composed of a cured product of a thermosetting resin. The use of a powder or granular material made of a cured product of a thermosetting resin makes it possible to control the porosity and the pore diameter with high accuracy.
That is, since the powder or granular material made of the cured product of the thermosetting resin is not softened by heating, pores having pore diameters corresponding to the particle size and amount of the cured product are formed. Therefore, the pore diameter and its distribution can be arbitrarily controlled, and an electrode plate having a sharp or broad pore diameter distribution can be obtained. Further, for the same reason, it is possible to obtain a homogeneous electrode plate having excellent gas permeability, electrical conductivity and mechanical strength.

【００３５】さらに、前記硬化物の粉粒体が加熱加圧成
形時に軟化しないため、厚みが１ｍｍ以下と薄く、１０
００ｍｍ×１０００ｍｍ程度の大きな面積であっても、
脱型時などに反り及び膨れが発生せず、均一性及び寸法
安定性の優れた電極基板が得られる。また、炭化又は黒
鉛化処理時にも気孔形成剤は再軟化しないため、電極板
の反り、膨れ、割れ等が発生せず製造工程での歩留まり
が非常に高い。Furthermore, since the powdered or granular material of the cured product does not soften during heat and pressure molding, the thickness is as thin as 1 mm or less and 10
Even with a large area of about 00 mm × 1000 mm,
Warping and swelling do not occur during demolding, and an electrode substrate having excellent uniformity and dimensional stability can be obtained. In addition, since the pore-forming agent does not re-soften during the carbonization or graphitization treatment, the electrode plate does not warp, swell, or crack, and the yield in the manufacturing process is very high.

【００３６】さらに好ましい有機粒状物質には、ピッチ
を含む有機粒状物質、特にメソフェーズピッチを含む有
機粒状物質が含まれる。なかでも、メソフェーズピッチ
を含む熱硬化性樹脂が好ましい。有機粒状物質における
ピッチの含有量は、１０〜７５重量％、好ましくは２５
〜６０重量％程度である。Further preferred organic particulate matter includes pitch-containing organic particulate matter, especially mesophase pitch-containing organic particulate matter. Of these, a thermosetting resin containing mesophase pitch is preferable. The content of pitch in the organic particulate matter is 10 to 75% by weight, preferably 25
It is about 60% by weight.

【００３７】上記粒状物質の粒径は、所望する細孔径な
どに応じて選択できるが、通常、０．１〜５００μｍ程
度、好ましくは５０〜３００μｍ程度である。The particle size of the above-mentioned granular material can be selected according to the desired pore size, etc., but is usually about 0.1 to 500 μm, preferably about 50 to 300 μm.

【００３８】有機粒状物質の割合は、所望する気孔率な
どに応じて適当に選択でき、例えば、前記繊維１００重
量部に対して１０〜５００重量部、好ましくは２５〜３
００重量部程度である。有機粒状物質の割合が、前記範
囲を外れると、電極基板の気孔率及び曲げ強度のいずれ
か一方の特性が低下し易い。The proportion of the organic particulate matter can be appropriately selected according to the desired porosity and the like, and for example, is 10 to 500 parts by weight, preferably 25 to 3 parts by weight with respect to 100 parts by weight of the fibers.
It is about 100 parts by weight. When the proportion of the organic particulate matter is out of the above range, the characteristics of either the porosity or the bending strength of the electrode substrate are likely to deteriorate.

【００３９】本発明の炭素質予備成形体は、メソフェー
ズピッチを含んでいる。このメソフェーズピッチによ
り、電極基板の熱伝導性が著しく向上する。メソフェー
ズピッチは、圧縮成形された炭素質予備成形体の焼成時
に、軟化しマトリックス内で溶融すると共に、空隙部に
流入し、発生する分解ガスにより、繊維と結合剤との間
に生成した空隙部や流路を通じて外部と連通し、連続気
泡を形成するようである。また、メソフェーズピッチ成
分が前記空隙部の内面で硬化し、炭化又は黒鉛化するも
のと推測される。そのため、メソフェーズピッチを用い
ない電極基板に比べて、電極基板のガス透過性、厚み方
向の熱伝導率および電気伝導率が顕著に向上する。The carbonaceous preform of the present invention contains mesophase pitch. The mesophase pitch significantly improves the thermal conductivity of the electrode substrate. The mesophase pitch softens and melts in the matrix during firing of the compression-molded carbonaceous preform, and flows into the voids, and the generated decomposition gas causes voids formed between the fibers and the binder. It seems that continuous air bubbles are formed by communicating with the outside through the channels. Further, it is presumed that the mesophase pitch component is hardened on the inner surface of the void portion and carbonized or graphitized. Therefore, the gas permeability, the thermal conductivity in the thickness direction, and the electrical conductivity of the electrode substrate are significantly improved as compared with the electrode substrate that does not use the mesophase pitch.

【００４０】メソフェーズピッチは、例えば、石油系及
び石炭系のいずれのメソフェーズピッチであってもよ
く、炭化収率５０重量％以上、好ましくは７０重量％以
上のメソフェーズピッチが使用できる。炭化収率が５０
重量％未満では電極基板の熱伝導性を高めるのが困難で
ある。また、メソフェーズピッチの軟化点は、１５０〜
４００℃、好ましくは２００〜４００℃程度である。な
お、前記炭素繊維化可能な繊維を用いる場合、前記炭素
繊維化可能な繊維よりも約２５〜１００℃以上高い軟化
点を有するメソフェーズピッチを用いる場合が多い。The mesophase pitch may be, for example, any petroleum-based or coal-based mesophase pitch, and a carbonization yield of 50% by weight or more, preferably 70% by weight or more can be used. Carbonization yield is 50
If it is less than wt%, it is difficult to increase the thermal conductivity of the electrode substrate. The softening point of mesophase pitch is 150 to
The temperature is 400 ° C, preferably about 200 to 400 ° C. When using the carbon fiber-forming fibers, mesophase pitch having a softening point higher than that of the carbon fiber-forming fibers by about 25 to 100 ° C. or more is often used.

【００４１】メソフェーズピッチの使用量は、熱伝導性
を高めることができる範囲、例えば、前記繊維１００重
量部に対して、１０〜２５０重量部、好ましくは２５〜
２００重量部程度である。メソフェーズピッチの割合が
１０重量部未満であると、電極基板の熱伝導率、気孔率
およびガス透過性が低下し易く、２５０重量部を越える
と、メソフェーズピッチの分解ガスによる膨れや割れが
生じ易く、気孔とその分布が不均一となり易い。The amount of mesophase pitch used is in the range capable of enhancing the thermal conductivity, for example, 10 to 250 parts by weight, preferably 25 to 100 parts by weight with respect to 100 parts by weight of the fibers.
It is about 200 parts by weight. If the proportion of mesophase pitch is less than 10 parts by weight, the thermal conductivity, porosity and gas permeability of the electrode substrate are likely to decrease, and if it exceeds 250 parts by weight, swelling or cracking due to decomposition gas of mesophase pitch is likely to occur. , Porosity and its distribution are likely to be non-uniform.

【００４２】メソフェーズピッチは、通常、粉粒状、例
えば、１００μｍ以下の粉末状で使用できる。メソフェ
ーズピッチの粒径が１００μｍを越えると、焼成に伴な
って、電極基板の表面に焼け、膨れなどの欠陥が生じ易
い。The mesophase pitch can usually be used in the form of powder, for example, a powder having a particle size of 100 μm or less. If the particle size of the mesophase pitch exceeds 100 μm, defects such as burning and swelling are likely to occur on the surface of the electrode substrate during firing.

【００４３】前記炭素質予備成形体は、抄紙構造を有す
る。抄紙構造とは、和紙の如く、繊維がランダムに配向
している構造を意味する。このような予備成形体は、例
えば、吸引成形法により得ることができる。前記吸引成
形法としては、例えば、（１）前記成分を含むスラリー
を多数の吸引孔が形成された吸引成形型により吸引し、
吸引成形型の表面に前記成分を堆積させる方法、（２）
吸引成形型内にスラリーを注入して吸引する方法などが
採用できる。吸引成形法により得られた吸引成形体の密
度は、吸引圧により容易にコントロールできる。The carbonaceous preform has a papermaking structure. The papermaking structure means a structure in which fibers are randomly oriented, like Japanese paper. Such a preform can be obtained by, for example, a suction molding method. As the suction molding method, for example, (1) a slurry containing the above components is sucked by a suction molding die having a large number of suction holes,
A method for depositing the above components on the surface of a suction mold, (2)
A method of injecting the slurry into the suction mold and sucking the slurry can be adopted. The density of the suction molded body obtained by the suction molding method can be easily controlled by the suction pressure.

【００４４】なお、スラリーの調製に際しては、炭素繊
維化可能な繊維及び／又は炭素繊維を叩解し、前記短繊
維としてもよい。スラリーの固形分濃度は、吸引成形性
を損わない範囲で選択でき、例えば、０．１〜２重量％
程度である。また、スラリーには、前記繊維、結合剤、
有機粒状物質及びメソフェーズピッチを均一に分散させ
るため、分散剤、安定剤、粘度調整剤、沈降防止剤など
を添加してもよく、増粘剤、紙力増強剤、凝集作用を有
する界面活性剤、特に高分子凝集剤や歩留り向上剤など
の種々の添加剤を添加してもよい。In the preparation of the slurry, the carbon fiber-forming fibers and / or the carbon fibers may be beaten to form the short fibers. The solid content concentration of the slurry can be selected within a range that does not impair the suction moldability, for example, 0.1 to 2% by weight.
It is a degree. Further, in the slurry, the fibers, binder,
In order to uniformly disperse the organic particulate matter and the mesophase pitch, a dispersant, a stabilizer, a viscosity modifier, an anti-settling agent, etc. may be added, and a thickener, a paper strength enhancer, and a surfactant having a cohesive action. Various additives such as a polymer coagulant and a yield improver may be added.

【００４５】吸引成形型から脱型した炭素質予備成形体
は、通常、加熱乾燥される。湿潤状態の炭素質予備成形
体の加熱乾燥は、常圧又は減圧下５０〜２００℃程度の
温度で行うことができる。The carbonaceous preform removed from the suction mold is usually heated and dried. The heat-drying of the wet carbonaceous preform can be carried out at a temperature of about 50 to 200 ° C. under normal pressure or reduced pressure.

【００４６】前記のような吸引成形法によると、従来の
乾式混合法では均一に混合することが困難な繊維状物質
と粉粒状物質を用いても、繊維状物質や粉粒状物質が偏
析せず、均質な炭素質予備成形体が得られる。また、炭
素質予備成形体を圧縮成形しても、成形体の均質性は維
持される。従って、有機粒状物質として熱により軟化す
る熱可塑性樹脂を用いても、可塑性樹脂の偏析に起因し
て加熱加圧成形及び焼成時に生じる成形体や電極板の反
りや膨れを著しく抑制でき、成形体や電極板の均一性を
高めることができる。According to the suction molding method as described above, even if the fibrous substance and the granular material which are difficult to be uniformly mixed by the conventional dry mixing method are used, the fibrous substance and the granular material are not segregated. A homogeneous carbonaceous preform is obtained. Even if the carbonaceous preform is compression-molded, the homogeneity of the compact is maintained. Therefore, even if a thermoplastic resin that is softened by heat is used as the organic particulate material, it is possible to remarkably suppress the warpage and swelling of the molded body or the electrode plate that occurs during the heating and pressurizing molding and firing due to the segregation of the plastic resin. The uniformity of the electrode plate can be improved.

【００４７】また、炭素質予備成形体を圧縮成形する場
合には、厚みが１ｍｍ未満であっても組成、密度及び厚
みが均質な成形体が得られる。特に、前記結合剤として
熱硬化性樹脂を使用する場合には、炭素質予備成形体が
プリプレグとして機能し、加熱加圧成形により、硬化し
て一体化する。そのため、厚みが１ｍｍ未満であっても
均質で均一な成形体が得られる。When the carbonaceous preform is compression-molded, a compact having a uniform composition, density and thickness can be obtained even if the thickness is less than 1 mm. In particular, when a thermosetting resin is used as the binder, the carbonaceous preform functions as a prepreg and is cured and integrated by heat and pressure molding. Therefore, even if the thickness is less than 1 mm, a homogeneous and uniform molded body can be obtained.

【００４８】また、繁雑な乾式混合の工程が不要である
ため、吸引成形により予備成形体を簡易に製造できる。
さらに、予備成形体を圧縮成形する場合、粉粒状の混合
物を金型内に均一に装填する必要がなく、シート状の予
備成形体を成形金型へ装填すればよく、装填作業が容易
であり、成形サイクルを短縮でき、成形効率、ひいては
電極基板の生産効率を高めることができる。Further, since a complicated dry mixing step is unnecessary, a preform can be easily manufactured by suction molding.
Furthermore, when the preform is compression-molded, it is not necessary to uniformly load the powder-granular mixture into the mold, and it is sufficient to load the sheet-form preform into the mold, which facilitates the loading operation. In addition, the molding cycle can be shortened, and the molding efficiency, and thus the electrode substrate production efficiency, can be improved.

【００４９】本発明の電極基板は、前記炭素質予備成形
体を圧縮成形、好ましくは加熱加圧成形し、炭化又は黒
鉛化することにより製造できる。前記圧縮成形により、
成形体の均質性がさらに高まる。The electrode substrate of the present invention can be produced by compression-molding the carbonaceous preform, preferably by heating and pressurizing, and carbonizing or graphitizing. By the compression molding,
The homogeneity of the molded body is further enhanced.

【００５０】炭素質予備成形体の圧縮成形は、慣用の方
法、例えば、金型プレス又はローラーによるプレス等の
方法で行なうことができる。圧縮成形は成形体の均一性
を高めるため加熱下で行うのが好ましい。加熱温度は、
適当に選択できるが、通常、１００〜２５０℃程度であ
る。成形圧は、所望する電極板の密度や厚みなどに応じ
て選択でき、例えば、３０〜７５０ｋｇｆ／ｃｍ² 、好
ましくは５０〜５００ｋｇｆ／ｃｍ² 程度である。The compression molding of the carbonaceous preform can be carried out by a conventional method such as a die press or a roller press. The compression molding is preferably performed under heating in order to improve the uniformity of the molded product. The heating temperature is
Although it can be appropriately selected, it is usually about 100 to 250 ° C. The molding pressure can be selected according to the desired density and thickness of the electrode plate, and is, for example, about 30 to 750 kgf / cm ² , preferably about 50 to 500 kgf / cm ² .

【００５１】炭素質予備成形体を、圧縮成形した後、成
形体は炭化又は黒鉛化する焼成工程に供される。焼成温
度は、８００℃以上、好ましくは１０００〜３０００℃
程度である。焼成は、真空下または不活性ガス雰囲気中
で行われる。不活性ガスとしては、窒素、ヘリウム、ア
ルゴン等が使用できる。After compression molding of the carbonaceous preform, the compact is subjected to a firing step of carbonizing or graphitizing. The firing temperature is 800 ° C. or higher, preferably 1000 to 3000 ° C.
It is a degree. The firing is performed under vacuum or in an inert gas atmosphere. Nitrogen, helium, argon or the like can be used as the inert gas.

【００５２】このようにして得られた炭素質の電極基板
は、予備成形体が均質であるため、厚みが１ｍｍ未満で
あっても気孔径が均一であり、機械的強度も大きく、ま
た優れたガス透過性、導電性および熱伝導性を有する。
特に、メソフェーズピッチを含む前記組成の炭素質予備
成形体を用いて得られた電極基板は、熱伝導性に優れて
いる。The carbonaceous electrode substrate thus obtained has a uniform preform, so that even if the thickness is less than 1 mm, the pore size is uniform, the mechanical strength is large, and it is excellent. It has gas permeability, electrical conductivity, and thermal conductivity.
In particular, the electrode substrate obtained by using the carbonaceous preform having the above composition containing mesophase pitch has excellent thermal conductivity.

【００５３】前記炭素質予備成形体の焼成に際して、各
成分は、次のように機能すると推測される。すなわち、
予備成形体を加熱加圧成形すると、結合剤が溶融して固
化又は硬化し、成形体が生成する。この成形体を例えば
１５０℃以上の温度で焼成すると、有機粒状物質の分解
ガスにより気孔が生成する。また、有機粒状物質として
熱硬化性樹脂を用いる場合には、有機粒状物質の形状に
対応した気孔が生成し、気孔径とその分布を任意にコン
トロールできる。焼成温度が、メソフェーズピッチの軟
化又は分解開始温度以上、例えば、２００℃以上となる
と、メソフェーズピッチも軟化しガスを発生し、軟化部
や気孔部を通じて分解ガスが外部へ放出され、外部へ通
じる網目状の気孔が形成され、ガス透過性が顕著に向上
する。また、気孔にメソフェーズピッチ成分が流入し、
例えば、４５０℃を越えると、メソフェーズピッチが固
化する。このようにして生成した電極基板の気孔は、少
なくとも厚み方向に連続して貫通しているようであり、
その気孔の内面は、熱伝導性を高める上で有用なメソフ
ェーズピッチ成分の炭化物でコートされるようである。
そして、高温、例えば、２０００℃以上、特に２４００
℃以上で焼成することにより、電極基板として優れたガ
ス透過性（例えば、ガス透過率７００ｍｌ・ｍｍ／ｃｍ
² ・ｈｒ・ｍｍＡｑ以上のガス透過率）、熱伝導性およ
び電気伝導性を発現する。特に電極基板の厚み方向の熱
伝導性および電気伝導性が高い。When the carbonaceous preform is fired, each component is presumed to function as follows. That is,
When the preform is heated and pressure-molded, the binder is melted and solidified or cured to form a compact. When this molded body is fired at a temperature of 150 ° C. or higher, for example, pores are generated by the decomposition gas of the organic particulate matter. When a thermosetting resin is used as the organic particulate matter, pores corresponding to the shape of the organic particulate matter are generated, and the pore diameter and its distribution can be controlled arbitrarily. When the firing temperature is equal to or higher than the softening or decomposition start temperature of the mesophase pitch, for example, 200 ° C. or higher, the mesophase pitch is also softened to generate a gas, and the decomposition gas is released to the outside through the softening portion and the pores, and is a network communicating to the outside. -Shaped pores are formed, and the gas permeability is significantly improved. Also, the mesophase pitch component flows into the pores,
For example, when the temperature exceeds 450 ° C., the mesophase pitch solidifies. The pores of the electrode substrate thus generated seem to penetrate continuously at least in the thickness direction,
The inner surface of the pores appears to be coated with a carbide of the mesophase pitch component, which is useful in enhancing thermal conductivity.
And high temperature, for example 2000 ° C. or higher, especially 2400
Excellent gas permeability as an electrode substrate by firing at ℃ or higher (for example, gas permeability 700 ml · mm / cm
^It exhibits a gas permeability of ² · hr · mmAq or more), thermal conductivity, and electrical conductivity. Particularly, the thermal conductivity and the electrical conductivity in the thickness direction of the electrode substrate are high.

【００５４】また、炭素繊維化可能な繊維を含む成形体
を焼成すると、炭素繊維化可能な繊維は、例えば１５０
℃以上の温度で分解ガスを発生し、繊維の収縮に伴なっ
て、成形体の繊維と結合剤との界面に沿って空隙及び／
又は流路が生成し始める。炭素繊維化可能な繊維は、例
えば、７００℃まで分解ガスを発生し、収縮する。ま
た、ピッチを含む熱硬化性樹脂を有機粒状物質として用
いると、有機物質の分解にやや遅れて有機粒状物質中の
ピッチが軟化分解し、有機粒状物質によって形成された
気孔と外部とを繋ぐ通路が形成される。さらに、メソフ
ェーズピッチの軟化と生成するガスにより、さらに網目
状の気孔が発達し、ガス透過性、熱伝導性および導電性
がさらに向上する。そのため、例えば、ガス透過率７０
０ｍｌ・ｍｍ／ｃｍ² ・ｈｒ・ｍｍＡｑ以上、好ましく
は１０００ｍｌ・ｍｍ／ｃｍ² ・ｈｒ・ｍｍＡｑ以上と
いう高いガス透過性、および熱伝導率７Ｗ／ｍＫ以上の
熱伝導性を有する電極基板を得ることもできる。When a molded product containing carbon fiber-forming fibers is fired, the carbon fiber-forming fibers are, for example, 150
Decomposition gas is generated at a temperature of ℃ or more, and as the fiber shrinks, voids and / or voids are formed along the interface between the fiber of the molded article and the binder.
Or the flow path begins to be created. Fibers that can be made into carbon fibers generate decomposed gas up to 700 ° C. and shrink. When a thermosetting resin containing pitch is used as the organic particulate material, the pitch in the organic particulate material is softened and decomposed slightly after the decomposition of the organic material, and the passages connecting the pores formed by the organic particulate material and the outside are formed. Is formed. Further, the softening of the mesophase pitch and the generated gas further develop the mesh-like pores to further improve the gas permeability, the thermal conductivity and the conductivity. Therefore, for example, the gas permeability 70
^{0ml · mm / cm 2 · hr} · mmAq or more, preferably to obtain high gas permeability of ^{1000ml · mm / cm 2 · hr} · mmAq or higher, and an electrode substrate having a thermal conductivity of 7W / mK or more thermally conductive You can also

【００５５】生成した電極基板は、焼成前の炭素質予備
成形体が均質であるため、前記炭素繊維化可能な繊維に
より形成された炭素繊維及び／又は炭素繊維によって補
強された均質な構造を有する。しかも、炭素繊維により
電極基板の面方向及び厚み方向に収縮するのを抑制で
き、均一な電極基板を得ることができる。The produced electrode substrate has a homogeneous structure reinforced by carbon fibers and / or carbon fibers formed of the fibers capable of being carbon fiber, because the carbonaceous preform before firing is homogeneous. . Moreover, it is possible to prevent the carbon fibers from contracting in the surface direction and the thickness direction of the electrode substrate, and it is possible to obtain a uniform electrode substrate.

【００５６】[0056]

【発明の効果】本発明の炭素質予備成形体は、前記成分
を含む抄紙構造を有しているので、有機粒状物質の偏析
を顕著に抑制でき、均質性に優れる。また、炭素質予備
成形体がメソフェーズピッチを含む。そのため、細孔径
とその分布を任意に精度よくコントロールでき、均質
性、熱伝導性、ガス透過性、電気伝導性に優れる電極基
板を得ることができる。特に有機粒状物質として熱硬化
性樹脂の硬化物やピッチを含む熱硬化性樹脂の硬化物を
用いる場合には、電極基板の細孔径とその分布をさらに
精度よくコントロールでき、均質な細孔径分布を有する
と共に、均一性及び寸法安定性に優れる電極基板を得る
ことができる。Since the carbonaceous preform of the present invention has a papermaking structure containing the above-mentioned components, segregation of the organic particulate matter can be remarkably suppressed and the homogeneity is excellent. Further, the carbonaceous preform contains mesophase pitch. Therefore, the pore diameter and its distribution can be arbitrarily and accurately controlled, and an electrode substrate having excellent homogeneity, thermal conductivity, gas permeability, and electrical conductivity can be obtained. In particular, when using a cured product of a thermosetting resin or a cured product of a thermosetting resin containing pitch as the organic particulate material, the pore size and its distribution of the electrode substrate can be controlled more accurately, and a uniform pore size distribution can be obtained. It is possible to obtain the electrode substrate having the uniformity and the dimensional stability.

【００５７】また、本発明の方法では、熱可塑性樹脂の
偏析が抑制された均質な炭素質予備成形体を、吸引成形
という簡単な方法で効率よく製造できる。Further, according to the method of the present invention, a homogeneous carbonaceous preform in which segregation of the thermoplastic resin is suppressed can be efficiently produced by a simple method called suction molding.

【００５８】さらに、本発明の方法によると、前記の如
き優れた特性を有する電極基板を生産性よく製造でき
る。Further, according to the method of the present invention, the electrode substrate having the above-mentioned excellent characteristics can be manufactured with high productivity.

【００５９】[0059]

【実施例】以下に、実施例に基づいて本発明をより詳細
に説明する。EXAMPLES The present invention will be described in more detail based on the following examples.

【００６０】実施例１ 結合剤としてフェノール樹脂［群栄化学工業（株）製、
商品名レジトップＰＳ−４１０１、炭化収率６０重量
％］１００重量部、平均繊維長０．７ｍｍの炭素繊維
［（株）ドナック製、商品名ドナカーボＳ−２４４］１
００重量部、有機粒状物質としてエポキシ樹脂硬化物
［油化シェル（株）製、商品名エピコート８１５、炭化
収率１０重量％］の粉末（粒径２０〜８０μｍ）２５０
重量部、及び軟化点３２０℃、炭化収率８０重量％のメ
ソフェーズピッチの粉末［大阪瓦斯（株）製、２００メ
ッシュ粉砕品］１００重量部を水中に分散させ、均一な
スラリーを調製した。Example 1 Phenolic resin as a binder [manufactured by Gunei Chemical Industry Co., Ltd.,
Product name REGITOP PS-4101, carbonization yield 60% by weight] 100 parts by weight, carbon fiber having an average fiber length of 0.7 mm [manufactured by Donac, Inc., product name DonaCarbo S-244] 1
100 parts by weight, powder (particle size 20-80 μm) of an epoxy resin cured product [produced by Yuka Shell Co., Ltd., trade name Epicoat 815, carbonization yield 10% by weight] as an organic particulate substance 250
100 parts by weight of mesophase pitch powder having a softening point of 320 ° C. and a carbonization yield of 80% by weight [200 mesh pulverized product manufactured by Osaka Gas Co., Ltd.] were dispersed in water to prepare a uniform slurry.

【００６１】そして、底面に多数の吸引用小孔を形成し
た吸引成形型（６００ｍｍ×６００ｍｍ）内に、吸引を
行いながら上記のスラリーを流し込み、成形用型の底面
に堆積させた。形成された湿潤状態の平板を型から取り
外し、１００℃で４時間乾燥した。こうして得られた抄
紙構造の予備成形体の寸法は、厚み１０ｍｍ×６００ｍ
ｍ×６００ｍｍであり、その嵩密度は０．２ｇ／ｃｍ³
であった。Then, the above-mentioned slurry was poured into a suction mold (600 mm × 600 mm) having a large number of small holes for suction formed on the bottom face while being sucked, and deposited on the bottom face of the mold. The wet plate thus formed was removed from the mold and dried at 100 ° C. for 4 hours. The thus obtained preform having a papermaking structure has a thickness of 10 mm × 600 m.
m × 600 mm and its bulk density is 0.2 g / cm ³
Met.

【００６２】次いで、この予備成形体を、６００ｍｍ×
６００ｍｍの平板金型に入れ、プレス温度１６５℃、成
形圧１５０ｋｇｆ／ｃｍ² で２０分間加熱加圧成形して
硬化させ、厚み１ｍｍ、密度１．３ｇ／ｃｍ³ の成形体
を得た。この成形体を、２２０℃の温度で４時間放置し
て硬化させた後、黒鉛板に挾み、３０℃／時の昇温速度
で２７００℃まで昇温し、同温度で３時間黒鉛化処理す
ることにより、炭素質の電極基板を得た。Then, this preform is 600 mm ×
The mixture was placed in a flat plate mold of 600 mm, heated and pressed at a pressing temperature of 165 ° C. and a molding pressure of 150 kgf / cm ² for 20 minutes for curing, and a molded body having a thickness of 1 mm and a density of 1.3 g / cm ³ was obtained. This molded body is left to cure at a temperature of 220 ° C. for 4 hours, then is sandwiched between graphite plates, heated to 2700 ° C. at a heating rate of 30 ° C./hour, and graphitized at the same temperature for 3 hours. By doing so, a carbonaceous electrode substrate was obtained.

【００６３】実施例２ 実施例１と同様にして得られた抄紙構造の予備成形体の
成形圧を８０ｋｇｆ／ｃｍ² とする以外は、実施例１と
同様に加圧成形し、厚み１．３ｍｍ、密度１．０ｇ／ｃ
ｍ³ の成形体を得た。この成形体を実施例１と同様に処
理して炭素質の電極基板を得た。Example 2 A preform having a papermaking structure obtained in the same manner as in Example 1 was press-molded in the same manner as in Example 1 except that the molding pressure was 80 kgf / cm ^2, and the thickness was 1.3 mm. , Density 1.0 g / c
A molded body of m ³ was obtained. This molded body was treated in the same manner as in Example 1 to obtain a carbonaceous electrode substrate.

【００６４】比較例１ 実施例１で用いたフェノール樹脂１００重量部、平均繊
維長０．７ｍｍの炭素繊維１００重量部、及び有機粒状
物質としてポリビニルアルコール［（株）クラレ製、粒
径２０〜３０μｍ］２５０重量部を乾式混合した。この
例では、メソフェーズピッチの粉末は混合しなかった。Comparative Example 1 100 parts by weight of the phenol resin used in Example 1, 100 parts by weight of carbon fibers having an average fiber length of 0.7 mm, and polyvinyl alcohol [made by Kuraray Co., Ltd., particle size 20 to 30 μm] as an organic particulate substance. ] 250 parts by weight were dry mixed. In this example, the mesophase pitch powder was not mixed.

【００６５】この混合物を、６００ｍｍ×６００ｍｍの
平板金型に入れ、プレス温度１６５℃、成形圧１５０ｋ
ｇｆ／ｃｍ² で２０分間加熱加圧成形し、厚み１ｍｍの
硬化板を得た。この硬化板を、２２０℃の温度で４時間
放置して硬化させた後、黒鉛板に挾み、３０℃／時の昇
温速度で２７００℃まで昇温し、同温度で３時間黒鉛化
処理することにより、炭素質の電極基板を得た。This mixture was put into a 600 mm × 600 mm flat plate mold, the press temperature was 165 ° C., the molding pressure was 150 k.
It was heat-pressed and molded at gf / cm ² for 20 minutes to obtain a cured plate having a thickness of 1 mm. This cured plate is left to cure at 220 ° C. for 4 hours, then sandwiched between graphite plates, heated to 2700 ° C. at a heating rate of 30 ° C./hour, and graphitized at the same temperature for 3 hours. By doing so, a carbonaceous electrode substrate was obtained.

【００６６】実施例３ 結合剤としてフェノール樹脂［鐘紡（株）製、商品名ベ
ルパールＳ−８９９、炭化収率６５重量％］１００重量
部、平均繊維長０．７ｍｍの炭素繊維［（株）ドナッ
ク、商品名ドナカーボＳ−２４４］１００重量部、有機
粒状物質として不飽和ポリエステル樹脂硬化物［武田薬
品工業（株）製、商品名ポリマール９８０２、炭化収率
１０重量％］の粉末（粒径５０〜３００μｍ）１００重
量部、及び軟化点３２０℃、炭化収率８０重量％のメソ
フェーズピッチの粉末［大阪瓦斯（株）製、２００メッ
シュ粉砕品］１００重量部を水中に分散させ、均一なス
ラリーを調製し、実施例１と同様にして、炭素質の電極
基板を得た。Example 3 100 parts by weight of a phenol resin as a binder [Kanebo Co., Ltd., trade name Bell Pearl S-899, carbonization yield 65% by weight], carbon fiber having an average fiber length of 0.7 mm [DONAC CO., LTD. , Donacarbo S-244], 100 parts by weight, an unsaturated polyester resin cured product as an organic particulate material [Takeda Yakuhin Kogyo Co., Ltd., trade name Polymer 9802, carbonization yield 10% by weight] powder (particle size 50- 300 μm) 100 parts by weight, and 100 parts by weight of mesophase pitch powder having a softening point of 320 ° C. and a carbonization yield of 80% by weight [Osaka Gas Co., Ltd., 200 mesh pulverized product] are dispersed in water to prepare a uniform slurry. Then, in the same manner as in Example 1, a carbonaceous electrode substrate was obtained.

【００６７】実施例４ メソフェーズピッチの粉末の使用量を１００重量部から
１５０重量部に変更する以外、実施例３と同様にして、
炭素質の電極基板を得た。Example 4 The procedure of Example 3 was repeated except that the amount of mesophase pitch powder used was changed from 100 parts by weight to 150 parts by weight.
A carbonaceous electrode substrate was obtained.

【００６８】実施例５ 実施例３と同様にした得られた抄紙構造の予備成形体の
成形圧を４０ｋｇｆ／ｃｍ² とする以外、実施例３と同
様にして加圧成形し、厚み１．６ｍｍ、密度０．８ｇ／
ｃｍ³ の成形体を得た。この成形体を実施例１と同様に
処理して炭素質の電極基板を得た。Example 5 Pressure molding was carried out in the same manner as in Example 3 except that the molding pressure of the paper-making structure preform obtained in the same manner as in Example 3 was 40 kgf / cm ^2, and the thickness was 1.6 mm. , Density 0.8 g /
A molded body of cm ³ was obtained. This molded body was treated in the same manner as in Example 1 to obtain a carbonaceous electrode substrate.

【００６９】比較例２ メソフェーズピッチの粉末を用いることなく、実施例２
と同様にして、成形及び焼成し、炭素質の電極基板を得
た。Comparative Example 2 Example 2 was carried out without using the powder of mesophase pitch.
In the same manner as above, molding and firing were performed to obtain a carbonaceous electrode substrate.

【００７０】実施例１〜５及び比較例１，２で得られた
電極基板の気孔率、曲げ強度、圧縮強度、ガス透過率、
厚み方向の体積固有抵抗及び熱伝導率を測定したとこ
ろ、表１に示す結果を得た。The electrode substrates obtained in Examples 1 to 5 and Comparative Examples 1 and 2 had porosity, bending strength, compressive strength, gas permeability,
When the volume resistivity and the thermal conductivity in the thickness direction were measured, the results shown in Table 1 were obtained.

【００７１】[0071]

【表１】 表１より、実施例１〜５で得られた電極基板は、比較例
１，２で得られた電極基板と比べて、特にガス透過性お
よび厚み方向の熱伝導率が優れている。[Table 1] From Table 1, the electrode substrates obtained in Examples 1 to 5 are particularly excellent in gas permeability and thermal conductivity in the thickness direction as compared with the electrode substrates obtained in Comparative Examples 1 and 2.

【００７２】実施例６〜８ 炭素繊維化可能な繊維としてのレーヨン繊維（大和紡績
（株）製、ＳＡレーヨン、３０μｍφ×３ｍｍ）、炭素
繊維（（株）ドナック製、ドナカーボＳ−３３１、１８
μｍφ×３ｍｍ）、結合剤としてフェノール樹脂（鐘紡
（株）製、ベルパールＳ−８９９、炭化収率６５重量
％）、石油系メソフェーズピッチ（三菱瓦斯化学（株）
製、軟化点３１０℃、１００μｍ以下、炭化収率８０重
量％）および有機粒状物質を表２に示す割合で水中に分
散させ、均一なスラリーを調製した。このスラリーを用
いて吸引成形法により湿式抄紙し、抄紙体（３００ｍｍ
×３００ｍｍ×厚み１０ｍｍ、嵩密度０．２ｇ／ｃ
ｍ³ ）を作製した。Examples 6 to 8 Rayon fiber (manufactured by Daiwa Boshoku Co., Ltd., SA rayon, 30 μmφ × 3 mm), carbon fiber (Donac Co., Ltd., Donacarb S-331, 18) as carbon fiber convertible fibers
μmφ × 3 mm), phenol resin as a binder (Kanebo Co., Ltd., Bell Pearl S-899, carbonization yield 65% by weight), petroleum mesophase pitch (Mitsubishi Gas Chemical Co., Ltd.)
Manufacturing, softening point 310 ° C., 100 μm or less, carbonization yield 80% by weight) and organic particulate matter were dispersed in water at a ratio shown in Table 2 to prepare a uniform slurry. Wet papermaking by suction molding method using this slurry, papermaking body (300 mm
× 300 mm × thickness 10 mm, bulk density 0.2 g / c
m ³ ) was prepared.

【００７３】なお、前記有機粒状物質としては、不飽和
ポリエステル樹脂（武田薬品工業（株）製、商品名ポリ
マール９８０２、炭化収率１０重量％）５０重量％と上
記メソフェーズピッチ粉５０重量％とを混合し、硬化さ
せた後、粉砕した粉粒状物（粒径５０〜１２０μｍ）を
用いた。As the organic particulate material, 50% by weight of an unsaturated polyester resin (trade name: Polymer 9802, carbonization yield: 10% by weight, manufactured by Takeda Pharmaceutical Co., Ltd.) and 50% by weight of the above mesophase pitch powder are used. After mixing and curing, powdered particles (particle size 50 to 120 μm) were used.

【００７４】抄紙体を乾燥し、１７０℃で３０分間加熱
プレスして硬化させ、嵩密度０．８〜１．０ｇ／ｃｍ³
の成形体を得た。得られた成形体を、窒素ガス雰囲気
中、２７００℃で焼成し、電極基板を作製した。The papermaking body is dried, heated and pressed at 170 ° C. for 30 minutes to be cured, and has a bulk density of 0.8 to 1.0 g / cm ^3.
A molded body of was obtained. The obtained molded body was fired at 2700 ° C. in a nitrogen gas atmosphere to produce an electrode substrate.

【００７５】実施例１０〜１１ 有機粒状物質として、メソフェーズピッチを４０重量％
含む前記エポキシ樹脂の硬化物の粉粒状物を用いると共
に、実施例６で用いた炭素繊維、レーヨン繊維、フェノ
ール樹脂およびメソフェーズピッチ粉を表２に示す割合
で用いる以外、実施例６〜９と同様にして、電極基板を
作製した。Examples 10 to 11 Mesophase pitch of 40% by weight was used as the organic particulate material.
Same as Examples 6 to 9 except that the powdered or granular material of the epoxy resin containing is used and the carbon fiber, rayon fiber, phenol resin, and mesophase pitch powder used in Example 6 are used in the ratios shown in Table 2. Then, the electrode substrate was produced.

【００７６】実施例１２〜１４ 炭素繊維化可能な繊維として、ポリアクリロニトリル繊
維［東邦ベスロン（株）製、パイロメックス］を用いる
と共に、実施例６で用いた炭素繊維、フェノール樹脂お
よびメソフェーズピッチ粉、実施例１０で用いたメソフ
ェーズピッチを含むエポキシ樹脂の硬化物の粉粒状物を
表３に示す割合で用いる以外、実施例１０〜１１と同様
にして、電極基板を作製した。Examples 12 to 14 Polyacrylonitrile fiber [Pyromex manufactured by Toho Bethlon Co., Ltd.] was used as the carbon fiber-forming fiber, and the carbon fiber, phenol resin and mesophase pitch powder used in Example 6 were used. An electrode substrate was produced in the same manner as in Examples 10 to 11, except that the powdered or granular material of the cured epoxy resin containing mesophase pitch used in Example 10 was used in the proportions shown in Table 3.

【００７７】比較例３〜１３ 下記の成分を表３及び表４に示す割合で用いる以外、実
施例３と同様にして、電極基板を作製した。Comparative Examples 3 to 13 Electrode substrates were prepared in the same manner as in Example 3 except that the following components were used in the ratios shown in Tables 3 and 4.

【００７８】炭素繊維化可能な繊維：（１）実施例６の
レーヨン繊維、および （２）実施例１２のポリアクリロニトリル繊維 炭素繊維：実施例１の炭素繊維 フェノール樹脂：実施例１のフェノール樹脂 有機粒状物質：（１）実施例３の不飽和ポリエステルの
硬化物の粉末、 （２）実施例１のエポキシ樹脂の硬化物の粉末、および （３）ポリスチレンの粉末（粒径２０〜８０μｍ） そして、実施例６〜１４および比較例３〜１３で得られ
た電極基板の特性を測定したところ、表２〜表４に示す
結果を得た。Fibers that can be made into carbon fibers: (1) rayon fiber of Example 6 and (2) polyacrylonitrile fiber of Example 12 carbon fiber: carbon fiber of Example 1 phenolic resin: phenolic resin of Example 1 organic Granular substance: (1) Powder of cured product of unsaturated polyester of Example 3, (2) Powder of cured product of epoxy resin of Example 1, and (3) Powder of polystyrene (particle size 20 to 80 μm) When the characteristics of the electrode substrates obtained in Examples 6 to 14 and Comparative Examples 3 to 13 were measured, the results shown in Tables 2 to 4 were obtained.

【００７９】[0079]

【表２】 [Table 2]

【００８０】[0080]

【表３】 [Table 3]

【００８１】[0081]

【表４】 表２〜表４から明らかなように、実施例６〜１４の電極
基板は、比較例３〜１３の電極基板に比べて、ガス透過
性、厚み方向の熱伝導性が極めて高い。[Table 4] As is clear from Tables 2 to 4, the electrode substrates of Examples 6 to 14 have extremely high gas permeability and thermal conductivity in the thickness direction as compared with the electrode substrates of Comparative Examples 3 to 13.

───────────────────────────────────────────────────── フロントページの続き (72)発明者 中川 喜照 大阪市中央区平野町四丁目１番２号 大阪 瓦斯株式会社内 (72)発明者 岡本 一夫 大阪市中央区平野町四丁目１番２号 大阪 瓦斯株式会社内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yoshiteru Nakagawa Yoshiteru Nakagawa 4-1-2, Hiranocho, Chuo-ku, Osaka City Osaka Gas Co., Ltd. (72) Kazuo Okamoto 4-1-2, Hiranocho, Chuo-ku, Osaka No. within Osaka Gas Co., Ltd.

Claims (7)

【特許請求の範囲】[Claims] 【請求項１】 炭素繊維化可能な繊維及び／又は炭素繊
維、炭化収率４０〜７５重量％の結合剤、有機粒状物
質、およびメソフェーズピッチを含む抄紙構造の炭素質
予備成形体。1. A carbonaceous preform having a papermaking structure, which comprises carbonizable fibers and / or carbon fibers, a binder having a carbonization yield of 40 to 75% by weight, organic particulate matter, and mesophase pitch. 【請求項２】 有機粒状物質が、熱硬化性樹脂の硬化物
である請求項１記載の炭素質予備成形体。2. The carbonaceous preform according to claim 1, wherein the organic particulate matter is a cured product of a thermosetting resin. 【請求項３】 有機粒状物質が、ピッチを含む熱硬化性
樹脂の硬化物である請求項２記載の炭素質予備成形体。3. The carbonaceous preform according to claim 2, wherein the organic particulate matter is a cured product of a thermosetting resin containing pitch. 【請求項４】 炭素質予備成形体が、繊維１００重量部
に対して、結合剤２０〜２００重量部、有機粒状物質１
０〜５００重量部、およびメソフェーズピッチ１０〜２
５０重量部を含む請求項１記載の炭素質予備成形体。4. A carbonaceous preform comprises 20 to 200 parts by weight of a binder, 100 parts by weight of fibers, and 1 part of organic particulate matter.
0-500 parts by weight, and mesophase pitch 10-2
The carbonaceous preform according to claim 1, comprising 50 parts by weight. 【請求項５】 メソフェーズピッチの軟化点が１５０〜
４００℃である請求項１記載の炭素質予備成形体。5. The softening point of mesophase pitch is 150 to
The carbonaceous preform according to claim 1, which has a temperature of 400 ° C. 【請求項６】 炭素繊維化可能な繊維及び／又は炭素繊
維の短繊維、炭化収率４０〜７５重量％の結合剤、有機
粒状物質、およびメソフェーズピッチを含むスラリーを
吸引成形する抄紙構造の炭素質予備成形体の製造方法。6. A carbon having a papermaking structure for suction-forming a slurry containing carbon fiber-forming fibers and / or carbon fiber short fibers, a binder having a carbonization yield of 40 to 75% by weight, organic particulate matter, and mesophase pitch. For producing a high quality preform. 【請求項７】 請求項１記載の炭素質予備成形体を圧縮
成形し、炭化又は黒鉛化する電極基板の製造方法。7. A method for manufacturing an electrode substrate, comprising compression-molding the carbonaceous preform according to claim 1 to carbonize or graphitize.