JP2013136495A - Method for producing dense carbon thin plate, and carbon thin plate - Google Patents
Method for producing dense carbon thin plate, and carbon thin plate Download PDFInfo
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- JP2013136495A JP2013136495A JP2011289405A JP2011289405A JP2013136495A JP 2013136495 A JP2013136495 A JP 2013136495A JP 2011289405 A JP2011289405 A JP 2011289405A JP 2011289405 A JP2011289405 A JP 2011289405A JP 2013136495 A JP2013136495 A JP 2013136495A
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- 238000004519 manufacturing process Methods 0.000 title claims abstract description 41
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- KXGFMDJXCMQABM-UHFFFAOYSA-N 2-methoxy-6-methylphenol Chemical compound [CH]OC1=CC=CC([CH])=C1O KXGFMDJXCMQABM-UHFFFAOYSA-N 0.000 claims description 3
- 229920001568 phenolic resin Polymers 0.000 claims description 3
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- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 5
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- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 4
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- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
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- 244000025254 Cannabis sativa Species 0.000 description 1
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- 244000124853 Perilla frutescens Species 0.000 description 1
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
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- 239000011487 hemp Substances 0.000 description 1
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- 239000011261 inert gas Substances 0.000 description 1
- 230000002687 intercalation Effects 0.000 description 1
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Abstract
Description
本発明は、緻密質炭素薄板の製造方法、及び、該製造方法により製造される炭素薄板に関するものである。 The present invention relates to a method for producing a dense carbon thin plate, and a carbon thin plate produced by the production method.
ガス透過度の低い緻密質炭素薄板の製造方法として、従来、フェノール樹脂等の熱硬化性樹脂の溶液を紙に含浸させ、樹脂液が含浸した紙の複数枚を積層し圧着して積層体とし、その積層体を焼成して炭化させる方法が提案されている（例えば、特許文献１参照）。このようにして得られる炭素薄板は、非晶質の炭素からなり、燃料電池のセパレータなど、ガス不透過性と電気伝導性が要請される用途に用いられている。特許文献１では、得られる炭素薄板の電気伝導性を高めるために、紙または樹脂液に、黒鉛粉末や炭素繊維を含有させることも提案している。 As a method for producing a dense carbon sheet with low gas permeability, conventionally, a paper is impregnated with a solution of a thermosetting resin such as a phenol resin, and a plurality of sheets of paper impregnated with a resin solution are laminated and pressed to form a laminate. A method of firing and carbonizing the laminate has been proposed (see, for example, Patent Document 1). The carbon thin plate thus obtained is made of amorphous carbon, and is used for applications that require gas impermeability and electrical conductivity, such as fuel cell separators. Patent Document 1 proposes that paper or a resin liquid contain graphite powder or carbon fiber in order to increase the electric conductivity of the obtained carbon thin plate.
上記の製造方法では、焼成時の樹脂の分解によるガスの発生に伴い積層体において発泡し、得られる炭素薄板に多くの気孔が形成されて、ガス不透過性が不十分となるおそれがある。そこで、熱硬化性樹脂の溶液に、乾性油又はその構成脂肪酸を混合することが提案されている（特許文献２参照）。これにより、樹脂が変性して熱分解反応が穏やかとなり、気孔の形成が抑制されると考えられている。 In the production method described above, gas is generated due to decomposition of the resin during firing, foaming occurs in the laminate, and many pores are formed in the resulting carbon thin plate, which may result in insufficient gas impermeability. Therefore, it has been proposed to mix a drying oil or a constituent fatty acid thereof with a thermosetting resin solution (see Patent Document 2). Thereby, it is considered that the resin is denatured, the thermal decomposition reaction becomes gentle, and the formation of pores is suppressed.
また、炭素薄板のガス不透過性を高める目的で、紙の気孔に樹脂を十分に充填することを意図し、紙の平均気孔率、及び、紙に担持させる樹脂液の量を制御する方法も、提案されている（特許文献３参照）。更に、焼成時における亀裂の発生は、熱収縮の大きさに起因すると考え、樹脂液を含浸させる前の紙を、予め加熱してある程度収縮させておく方法も、提案されている（特許文献４参照）。 In addition, for the purpose of increasing the gas impermeability of the carbon thin plate, a method for controlling the average porosity of the paper and the amount of the resin liquid carried on the paper is intended to sufficiently fill the pores of the paper with resin. Have been proposed (see Patent Document 3). Furthermore, it is considered that the occurrence of cracks during firing is caused by the magnitude of thermal shrinkage, and a method in which paper before impregnation with a resin liquid is preliminarily heated and contracted to some extent has been proposed (Patent Document 4). reference).
しかしながら、上記の従来技術では、焼成前の積層体の厚さはせいぜい１．５ｍｍ程度にとどまっており、焼成後（炭化後）に得られる炭素薄板の厚さは０．５ｍｍ未満であった。そのため、より厚さの大きい炭素薄板が要請されていた。単純には、樹脂液を含浸させた紙を積層する枚数を増加させることを想到し得るが、その場合は層間に空隙が形成され、或いは、層間で剥離が生じ易くなるなど、ガス不透過性が低下してしまうおそれがある。 However, in the above prior art, the thickness of the laminate before firing is only about 1.5 mm, and the thickness of the carbon thin plate obtained after firing (after carbonization) is less than 0.5 mm. For this reason, a carbon thin plate having a larger thickness has been demanded. In simple terms, it can be envisaged to increase the number of sheets of paper impregnated with resin liquid, but in that case, voids are formed between the layers, or separation between layers is likely to occur. May decrease.
そこで、本発明は、上記の実情に鑑み、ガス不透過性を損なうことなく、従来に比べて厚さの大きい炭素薄板を製造することができる緻密質炭素薄板の製造方法、及び、該製造方法により製造される炭素薄板の提供を課題とするものである。 Therefore, in view of the above circumstances, the present invention provides a method for producing a dense carbon thin plate capable of producing a carbon thin plate having a thickness greater than that of the conventional one without impairing gas impermeability, and the production method. An object of the present invention is to provide a carbon thin plate manufactured by the above method.
上記の課題を解決するため、本発明にかかる緻密質炭素薄板の製造方法は、「セルロース繊維を原料とする紙に、乾性油または乾性油の構成脂肪酸を混合したフェノール樹脂を含む混合溶液を含浸させ、含浸紙を得る含浸工程と、前記含浸紙を乾燥させ、乾燥処理後含浸紙とする乾燥工程と、前記乾燥処理後含浸紙の複数枚を積層し圧着して積層体を得る積層圧着工程と、前記積層体を非酸化性雰囲気で焼成し炭化させる炭化工程とを具備し、前記乾燥工程は、前記乾燥処理後含浸紙の質量から揮発分及び前記紙の質量を除いた固形分の質量の前記乾燥処理後含浸紙の質量に対する割合が２５％〜５５％で、且つ、揮発分の質量の前記乾燥処理後含浸紙の質量に対する割合が２．５％〜５．５％となるように行われる」ものである。 In order to solve the above-mentioned problems, a method for producing a dense carbon thin plate according to the present invention is described as follows: “A paper solution made of cellulose fiber is impregnated with a mixed solution containing a dry resin or a phenol resin in which a constituent fatty acid of a dry oil is mixed. An impregnation step for obtaining an impregnated paper, a drying step for drying the impregnated paper to obtain an impregnated paper after drying treatment, and a laminated crimping step for laminating a plurality of the impregnated paper after the drying treatment to obtain a laminate. And a carbonization step of firing and carbonizing the laminate in a non-oxidizing atmosphere, and the drying step is a mass of solid content excluding volatile matter and the mass of the paper from the mass of the impregnated paper after the drying treatment. So that the ratio of the mass of the impregnated paper after the drying treatment to 25% to 55% and the ratio of the volatile matter mass to the mass of the impregnated paper after the drying treatment is 2.5% to 5.5%. Is done.
「セルロース繊維を原料とする紙」としては、木材パルプ、コウゾ、ミツマタ、麻、綿などの天然繊維、天然のセルロースの再生繊維（レーヨンなど）を原料とする紙を例示することができる。 Examples of the “paper made from cellulose fibers” include paper made from natural fibers such as wood pulp, mulberry, Mitsumata, hemp, and cotton, and natural cellulose regenerated fibers (such as rayon).
「乾性油または乾性油の構成脂肪酸」における「乾性油」としては、桐油、アマニ油、ケシ油、シソ油、エゴマ油、ベニバナ油、ヒマワリ油を例示することができる。また、これらとフェノール樹脂を含む「混合溶液」は、有機溶媒で濃度及び粘度を調整した溶液を使用することができ、有機溶媒としては、トルエン、アセトン、エタノール等を使用することができる。なお、以下では、フェノール樹脂、及び、乾性油または乾性油の構成脂肪酸との混合により変性したフェノール樹脂を総称して、単に「樹脂」と称することがある。 Examples of “drying oil” in “drying oil or constituent fatty acid of drying oil” include tung oil, linseed oil, poppy oil, perilla oil, sesame oil, safflower oil, and sunflower oil. Moreover, the "mixed solution" containing these and a phenol resin can use the solution which adjusted the density | concentration and the viscosity with the organic solvent, and toluene, acetone, ethanol etc. can be used as an organic solvent. Hereinafter, phenol resins and phenol resins modified by mixing with drying oil or fatty acids constituting drying oil may be collectively referred to simply as “resins”.
「非酸化性雰囲気」は、アルゴンガス等の不活性ガス、窒素ガス、これらの混合ガス雰囲気、または、真空雰囲気とすることができる。 The “non-oxidizing atmosphere” can be an inert gas such as argon gas, a nitrogen gas, a mixed gas atmosphere thereof, or a vacuum atmosphere.
「固形分の質量の乾燥処理後含浸紙の質量に対する割合」（以下、「固形分割合」と称することがある）は、主に混合溶液中の樹脂固形分の割合に影響を受ける。混合溶液中の樹脂固形分の割合が大きい場合は、混合溶液の粘度が大きくなり、紙への含浸が不十分となりやすい（紙の内部まで混合溶液が十分に浸透しにくい）と共に、焼成時に樹脂の熱分解により発生するガス量が増加する。一方、混合溶液中の樹脂固形分の割合が小さい場合は、混合溶液の紙への浸透性は高くなるが、紙に担持される樹脂量が少なくなり、積層体における各層の緻密度が低くなると共に、層間の接着が不十分となりやすく、得られる炭素薄板のガス不透過性が不十分となる。 The “ratio of the mass of the solid content to the mass of the impregnated paper after the drying treatment” (hereinafter sometimes referred to as “solid content ratio”) is mainly influenced by the ratio of the resin solid content in the mixed solution. When the ratio of the resin solid content in the mixed solution is large, the viscosity of the mixed solution increases and the paper is not sufficiently impregnated (the mixed solution is not easily penetrated into the inside of the paper). The amount of gas generated by the thermal decomposition of the increases. On the other hand, when the ratio of the resin solid content in the mixed solution is small, the permeability of the mixed solution to paper increases, but the amount of resin carried on the paper decreases and the density of each layer in the laminate decreases. At the same time, the adhesion between the layers tends to be insufficient, and the resulting carbon thin plate has insufficient gas impermeability.
また、「揮発分の質量の乾燥処理後含浸紙の質量に対する割合」（以下、「揮発分割合」と称することがある）は、乾燥工程を経て残存する揮発分の割合であり、主に乾燥温度・乾燥時間や混合溶液中の有機溶媒の割合に影響を受ける。乾燥温度が高い場合は乾燥開始時に混合溶液の紙への浸透が進行するが揮発分割合が小さくなりやすく、乾燥温度が低い場合は揮発分が残存しやすい。混合溶液中の有機溶媒の割合が小さい場合は、混合溶液の粘度が大きくなりやすく、紙への含浸が不十分となりやすい。一方、混合溶液中の有機溶媒の割合が大きい場合は、混合溶液の紙への浸透性は高くなるが、乾燥処理後含浸紙に気孔が残存し易く、得られる炭素薄板のガス不透過性が不十分となりやすい。 The “ratio of the mass of the volatile matter relative to the mass of the impregnated paper after the drying treatment” (hereinafter sometimes referred to as “the volatile matter percentage”) is a ratio of the volatile matter remaining after the drying step, and is mainly dried. It is affected by temperature, drying time and the proportion of organic solvent in the mixed solution. When the drying temperature is high, penetration of the mixed solution into the paper proceeds at the start of drying, but the volatile component ratio tends to decrease, and when the drying temperature is low, the volatile component tends to remain. When the proportion of the organic solvent in the mixed solution is small, the viscosity of the mixed solution tends to increase and the paper impregnation tends to be insufficient. On the other hand, when the proportion of the organic solvent in the mixed solution is large, the permeability of the mixed solution into the paper is high, but pores are likely to remain in the impregnated paper after the drying treatment, and the resulting carbon thin plate has a gas impermeability. It tends to be insufficient.
本発明者らは、検討の結果、乾燥処理後含浸紙における固形分割合及び揮発分割合を、共に所定の範囲内とすることにより、紙に含浸する樹脂量を十分なものとし、積層体における層間の接着性を良好なものとして含浸紙の多数枚の積層を可能とすると共に、焼成時の発泡や膨れを抑制できることを見出し、本発明に至ったものである。そして、上記構成の本発明によれば、後述のように、従来の炭素薄板と同等以上のガス不透過性を有しながら、従来の炭素薄板に比べて厚さの大きい炭素薄板を製造することができる。 As a result of the study, the inventors have determined that the amount of resin impregnated in the paper is sufficient by setting both the solid content ratio and the volatile content ratio in the impregnated paper after the drying treatment within a predetermined range. The present inventors have found that it is possible to laminate a large number of impregnated papers with good interlayer adhesion, and to suppress foaming and swelling during firing. And according to this invention of the said structure, as it mentions later, manufacturing a carbon thin plate with a thickness larger than the conventional carbon thin plate while having a gas impermeability equivalent to or higher than that of the conventional carbon thin plate. Can do.
本発明にかかる緻密質炭素薄板の製造方法は、上記構成に加え、「前記積層圧着工程は、１．５ＭＰａ〜５．０ＭＰａの圧力で行われる」ものとすることができる。 The manufacturing method of the dense carbon thin plate concerning this invention shall be "the said lamination | stacking crimping | compression-bonding process is performed by the pressure of 1.5 MPa-5.0 MPa" in addition to the said structure.
積層圧着工程における圧力が大きければ、積層体における層間の接着性を高めることができる反面、焼成時に樹脂の熱分解により発生するガスが層間から排出されにくくなり、積層体に膨れや層間剥離を生じ易いものとなる。本発明では、積層圧着工程における圧力を１．５ＭＰａ〜５．０ＭＰａの範囲とすることにより、熱分解により発生するガスが排出される経路が残る程度に、積層体において層間を接着させる。これにより、焼成時の膨れや剥離が抑制され、ガス不透過性の高い炭素薄板を、高い収率（良品の得られる割合）で製造することができる。 If the pressure in the lamination crimping process is high, the adhesion between the layers in the laminate can be increased, but the gas generated by the thermal decomposition of the resin during firing is less likely to be exhausted from the layers, causing swelling and delamination in the laminate. It will be easy. In the present invention, by adjusting the pressure in the lamination pressure bonding step to a range of 1.5 MPa to 5.0 MPa, the layers are bonded to each other to the extent that a path for discharging the gas generated by thermal decomposition remains. Thereby, the swelling and peeling at the time of baking are suppressed, and a carbon thin plate with high gas impermeability can be manufactured with a high yield (ratio in which a good product is obtained).
本発明にかかる緻密質炭素薄板の製造方法は、上記構成に加え、「前記炭化工程は、３．２℃／ｈｒ以上の昇温速度で行われる」ものとすることができる。 In addition to the above-described structure, the method for producing a dense carbon thin plate according to the present invention can be “the carbonization step is performed at a temperature increase rate of 3.2 ° C./hr or more”.
炭化工程における昇温速度が大き過ぎると、樹脂の熱分解が急速に進行し、積層体に発泡や膨れが生じ易いため、炭素薄板の収率（製造数における良品数の割合）が低下するおそれがある。そのため、従来では炭化工程に数十日から数カ月をかけていた。これに対し、上述の構成を備える本発明では、炭化工程における昇温速度を３．２℃／ｈｒ以上という従来に比べて大きな昇温速度としても、発泡や膨れを抑制して高い収率で炭素薄板を製造することができ、生産効率が高い。なお、昇温速度を３．２℃／ｈｒ以上、３．６℃／ｈｒ以下の範囲とすれば、工業生産規模での生産効率を確保しつつ、極めて高い収率で炭素薄板を製造することができ、より好適である。 If the heating rate in the carbonization process is too high, the thermal decomposition of the resin proceeds rapidly, and foaming and swelling are likely to occur in the laminate, which may reduce the yield of carbon thin plates (ratio of the number of non-defective products in the number of production). There is. Therefore, conventionally, the carbonization process took several tens of days to several months. On the other hand, in the present invention having the above-described configuration, even when the temperature rising rate in the carbonization step is 3.2 ° C./hr or more, which is larger than the conventional temperature rising rate, foaming and swelling are suppressed and the yield is high. Carbon sheet can be manufactured and production efficiency is high. If the heating rate is in the range of 3.2 ° C./hr or more and 3.6 ° C./hr or less, the carbon thin plate can be produced with an extremely high yield while ensuring the production efficiency on the industrial production scale. This is more preferable.
本発明にかかる緻密質炭素薄板の製造方法は、上記構成に加え、「前記炭化工程は、前記積層体を膨張黒鉛シート間に挟んだ状態で行われる」ものとすることができる。 In addition to the above configuration, the method for producing a dense carbon thin plate according to the present invention may be “the carbonization step is performed in a state where the laminate is sandwiched between expanded graphite sheets”.
膨張黒鉛シートは、層間化合物とした黒鉛を急激に加熱し、層間の物質をガス化して層間隔を押し広げ、その後圧延することにより得られる黒鉛シートであり、厚さ０．５ｍｍ〜２．０ｍｍのものを好適に使用することができる。なお、上記の従来技術では、反り等を防止することを目的として、積層体を“黒鉛板”に挟んだ状態で焼成することを開示しているが、この黒鉛板は機械加工上の制約から厚さが５ｍｍ以上の板材とならざるを得ず、本発明の膨張黒鉛シートとは異なる。 An expanded graphite sheet is a graphite sheet obtained by rapidly heating graphite as an intercalation compound, gasifying an interlayer material to widen a layer interval, and then rolling, and has a thickness of 0.5 mm to 2.0 mm. Can be preferably used. In the above prior art, for the purpose of preventing warpage and the like, it is disclosed that the laminate is fired in a state of being sandwiched between “graphite plates”. It must be a plate material having a thickness of 5 mm or more, and is different from the expanded graphite sheet of the present invention.
膨張黒鉛シートは、面方向の熱伝導率が大きい。従って、積層体を膨張黒鉛シートに挟んだ状態で炭化することにより、積層体における温度分布を均一に近付けることができる。また、膨張黒鉛シートは滑り性に優れる。そのため、膨張黒鉛シート間に挟まれた積層体は、膨張黒鉛シートに沿って滑らかに収縮し易い。従って、上記構成の本発明によれば、炭化工程における積層体の反りやうねり等を抑制し、変形のない炭素薄板を高い収率で製造することができる。 The expanded graphite sheet has a large thermal conductivity in the surface direction. Therefore, by performing carbonization with the laminate sandwiched between expanded graphite sheets, the temperature distribution in the laminate can be made closer to the uniform. Further, the expanded graphite sheet is excellent in slipperiness. Therefore, the laminate sandwiched between the expanded graphite sheets tends to contract smoothly along the expanded graphite sheet. Therefore, according to the present invention having the above-described configuration, it is possible to produce a carbon thin plate having no deformation while suppressing warpage or undulation of the laminate in the carbonization step.
本発明にかかる緻密質炭素薄板の製造方法は、上記構成に加え、「前記含浸工程は、前記紙として２質量％〜１２質量％の炭素質フィラーを含有する紙を使用し、または、前記混合溶液から揮発分を除去した固形分に対する炭素質フィラーの割合が１質量％〜１１質量％となる、炭素質フィラーを含有する前記混合溶液を使用して行われる」ものとすることができる。 The method for producing a dense carbon thin plate according to the present invention includes, in addition to the above configuration, “the impregnation step uses paper containing 2% by mass to 12% by mass of carbonaceous filler as the paper, or the mixing It is carried out using the above-mentioned mixed solution containing a carbonaceous filler in which the ratio of the carbonaceous filler to the solid content obtained by removing volatile components from the solution is 1% by mass to 11% by mass.
「炭素質フィラー」としては、黒鉛粉末、炭素繊維、カーボンブラック等を使用可能である。 As the “carbonaceous filler”, graphite powder, carbon fiber, carbon black and the like can be used.
炭化工程を経て得られる炭素薄板のマトリクスは非晶質の炭素であり、炭素材料としては電気伝導率が高いとは言えない。そこで、炭素質フィラーを紙または混合溶液に含有させることにより、製造される炭素薄板の電気伝導性を高めることができる。ところが、含有させる炭素質フィラーの量が多くなると、製造される炭素薄板のガス不透過性が低下する傾向がある。本発明によれば、所定範囲の割合で炭素質フィラーを含有する紙、または、所定範囲の割合で炭素質フィラーを含有する混合溶液を紙に含浸させることにより、電気伝導性を高める作用効果を得つつ、実用的なガス不透過性を備える炭素薄板を製造することができる。 The matrix of the carbon thin plate obtained through the carbonization step is amorphous carbon, and it cannot be said that the carbon material has high electrical conductivity. Then, the electrical conductivity of the carbon thin plate manufactured can be improved by containing a carbonaceous filler in paper or a mixed solution. However, when the amount of the carbonaceous filler to be contained increases, the gas impermeability of the produced carbon thin plate tends to decrease. According to the present invention, by impregnating paper with carbonaceous filler in a predetermined range or mixed solution containing carbonaceous filler in a predetermined range, the effect of increasing electrical conductivity is achieved. While being obtained, a carbon thin plate having practical gas impermeability can be produced.
本発明にかかる緻密質炭素薄板の製造方法は、上記構成に加え、「前記炭化工程の後に、炭化した前記積層体を非酸化性雰囲気で１７００℃〜２３００℃で焼成し黒鉛化させる黒鉛化工程を具備する」ものとすることができる。 The method for producing a dense carbon thin plate according to the present invention includes, in addition to the above-described configuration, “a graphitization step in which, after the carbonization step, the carbonized laminate is fired at 1700 ° C. to 2300 ° C. in a non-oxidizing atmosphere and graphitized. It can be included.
炭化工程を経て得られる非晶質炭素からなる炭素薄板を、更に１７００℃〜２３００℃で焼成することにより、非晶質炭素が黒鉛化し、電気伝導性の高い炭素薄板を製造することができる。ところが、黒鉛化した炭素の結晶が異常成長すると、ガス不透過性が低下すると共に、層間剥離が生じ易くなる。本発明では、黒鉛化の温度を２３００℃を超えない温度とすることにより、ガス不透過性を損なうことなく電気伝導性が高められ、層間剥離の抑制された炭素薄板を製造することができる。 By firing the carbon thin plate made of amorphous carbon obtained through the carbonization step at 1700 ° C. to 2300 ° C., the amorphous carbon is graphitized, and a carbon thin plate having high electrical conductivity can be produced. However, when graphitized carbon crystals grow abnormally, gas impermeability is lowered and delamination tends to occur. In the present invention, by setting the graphitization temperature not to exceed 2300 ° C., it is possible to produce a carbon thin plate in which electrical conductivity is improved and delamination is suppressed without impairing gas impermeability.
次に、本発明にかかる炭素薄板は、「非晶質炭素の炭素薄板であって、窒素ガス透過度が２×１０−１２ｃｃ／ｃｍ２・ｓｅｃ〜４×１０−７ｃｃ／ｃｍ２・ｓｅｃで、厚さが０．５ｍｍ〜２．４ｍｍである」ものである。 Next, the carbon thin plate according to the present invention is “a carbon thin plate of amorphous carbon having a nitrogen gas permeability of 2 × 10 −12 cc / cm 2 · sec to 4 × 10 −7 cc / cm 2. in seconds, the thickness is 0.5 mm to 2.4 mm ”.
上述の含浸工程、乾燥工程、積層圧着工程、及び、炭化工程を具備する緻密質炭素薄板の製造方法により、後述のように、従来の炭素薄板と同等以上のガス不透過性を有しながら、従来の炭素薄板に比べて厚さの大きい本構成の炭素薄板を得ることができる。すなわち、既述のように、従来技術では、焼成前の積層体の厚さはせいぜい１．５ｍｍにとどまっており、炭化工程を経て得られる炭素薄板の厚さは０．５ｍｍ未満であった。これに対し、上述の緻密質炭素薄板の製造方法によれば、従来に比べて厚さの大きい０．５ｍｍ以上の炭素薄板（非晶質炭素）を製造可能であり、少なくとも２．４ｍｍの厚さの炭素薄板を実現できることが確認された。なお、上述の含浸工程、乾燥工程、積層圧着工程、及び、炭化工程を具備する緻密質炭素薄板の製造方法によって、従来技術と同程度の厚さの炭素薄板（非晶質炭素）を得ることができることは、もちろんである。 By the above-described impregnation step, drying step, lamination pressure bonding step, and method for producing a dense carbon thin plate comprising a carbonization step, as described later, while having a gas impermeability equivalent to or higher than that of a conventional carbon thin plate, It is possible to obtain a carbon thin plate having the present configuration that is thicker than a conventional carbon thin plate. That is, as described above, in the prior art, the thickness of the laminate before firing is limited to 1.5 mm at most, and the thickness of the carbon thin plate obtained through the carbonization step is less than 0.5 mm. On the other hand, according to the above-described method for producing a dense carbon thin plate, it is possible to produce a carbon thin plate (amorphous carbon) having a thickness of 0.5 mm or more which is larger than the conventional one, and has a thickness of at least 2.4 mm. It was confirmed that a thin carbon plate could be realized. In addition, a carbon thin plate (amorphous carbon) having the same thickness as that of the prior art is obtained by the method for manufacturing a dense carbon thin plate having the above-described impregnation step, drying step, lamination pressure bonding step, and carbonization step. Of course you can.
また、本発明にかかる炭素薄板は、「黒鉛化した炭素薄板であって、窒素ガス透過度が２×１０−１１ｃｃ／ｃｍ２・ｓｅｃ〜８×１０−７ｃｃ／ｃｍ２・ｓｅｃで、厚さが０．４ｍｍ〜２．３ｍｍである」ものである。 Further, the carbon thin plate according to the present invention, the "a graphitized carbon sheet, a nitrogen gas permeability 2 × 10 -11 cc / cm 2 · sec~8 × 10 -7 cc / cm 2 · sec, The thickness is 0.4 mm to 2.3 mm ”.
上述の含浸工程、乾燥工程、積層圧着工程、炭化工程、及び、黒鉛化工程を具備する緻密質炭素薄板の製造方法により、後述のように、従来の炭素薄板と同等以上のガス不透過性を有しながら、従来の炭素薄板に比べて厚さの大きい本構成の炭素薄板を得ることができる。すなわち、従来技術では、焼成前の炭素薄板の厚さがせいぜい１．５ｍｍ程度と小さいため、これを炭化させ、更に黒鉛化させた炭素薄板の厚さは０．４ｍｍ未満となってしまう。これに対し、上述の含浸工程、乾燥工程、積層圧着工程、炭化工程、及び、黒鉛化工程を具備する緻密質炭素薄板の製造方法によれば、従来に比べて厚さの大きい０．４ｍｍ以上の炭素薄板（黒鉛化）を製造可能であり、少なくとも２．３ｍｍの厚さの炭素薄板を実現できることが確認された。なお、上述の含浸工程、乾燥工程、積層圧着工程、炭化工程、及び、黒鉛化工程を具備する緻密質炭素薄板の製造方法によって、従来技術と同程度の厚さの炭素薄板（黒鉛化）を得ることができることは、もちろんである。 As described later, the gas impermeability equivalent to or higher than that of a conventional carbon thin plate is obtained by the method for producing a dense carbon thin plate having the impregnation step, the drying step, the lamination pressure bonding step, the carbonization step, and the graphitization step. While having it, the carbon thin plate of this structure with a large thickness compared with the conventional carbon thin plate can be obtained. That is, in the prior art, the thickness of the carbon thin plate before firing is as small as about 1.5 mm, so the thickness of the carbon thin plate carbonized and graphitized is less than 0.4 mm. On the other hand, according to the method for producing a dense carbon thin plate having the above-described impregnation step, drying step, lamination pressure bonding step, carbonization step, and graphitization step, the thickness is 0.4 mm or more which is larger than the conventional one. It was confirmed that a carbon thin plate (graphitized) can be produced and a carbon thin plate having a thickness of at least 2.3 mm can be realized. In addition, a carbon thin plate (graphitization) having the same thickness as that of the prior art is produced by the method for producing a dense carbon thin plate having the above-described impregnation step, drying step, lamination pressure bonding step, carbonization step, and graphitization step. Of course you can get.
以上のように、本発明の効果として、ガス不透過性を損なうことなく、従来に比べて厚さの大きい炭素薄板を製造することができる緻密質炭素薄板の製造方法、及び、該製造方法により製造される炭素薄板を提供することができる。 As described above, as an effect of the present invention, a method for producing a dense carbon thin plate capable of producing a carbon thin plate having a larger thickness than the conventional one without impairing gas impermeability, and the production method. A manufactured carbon sheet can be provided.
以下、本発明の具体的な実施形態について、説明する。第一実施形態の緻密質炭素薄板の製造方法（以下、単に「製造方法」と称する）は、セルロース繊維を原料とする紙に、乾性油または乾性油の構成脂肪酸を混合したフェノール樹脂を含む混合溶液を含浸させ、含浸紙を得る含浸工程と、含浸紙を乾燥させ、乾燥処理後含浸紙とする乾燥工程と、乾燥処理後含浸紙の複数枚を積層し圧着して積層体を得る積層圧着工程と、積層体を非酸化性雰囲気で焼成し炭化させる炭化工程とを具備し、乾燥工程は、乾燥処理後含浸紙の質量から揮発分及び紙の質量を除いた固形分の質量の乾燥処理後含浸紙の質量に対する割合が２５％〜５５％で、且つ、揮発分の質量の乾燥処理後含浸紙の質量に対する割合が２．５％〜５．５％となるように行われるものである。 Hereinafter, specific embodiments of the present invention will be described. A method for producing a dense carbon thin plate according to the first embodiment (hereinafter simply referred to as “production method”) is a mixture comprising a phenol resin in which a dry fiber or a constituent fatty acid of a dry oil is mixed with paper using cellulose fibers as a raw material. An impregnation step for impregnating a solution to obtain an impregnated paper; a drying step for drying the impregnated paper to obtain an impregnated paper after drying treatment; And a carbonization step for firing and carbonizing the laminate in a non-oxidizing atmosphere, and the drying step is a drying treatment of the mass of the solid content excluding the volatile matter and the mass of the paper from the mass of the impregnated paper after the drying treatment. The ratio is 25% to 55% with respect to the mass of the post-impregnated paper, and the ratio of the mass of the volatile matter to the mass of the impregnated paper after the drying treatment is 2.5% to 5.5%. .
より具体的に説明すると、含浸工程で混合溶液を含浸させる紙としては、市販のクラフト紙、リンタ紙、クラフト・リンタ混抄紙を例示することができる。 More specifically, examples of the paper to be impregnated with the mixed solution in the impregnation step include commercially available kraft paper, linter paper, and kraft / linter mixed paper.
加えて、混合溶液を含浸させる紙として、紙の原料に炭素質フィラーを配合して抄紙することにより得られる、炭素質フィラーを含有する紙を使用することができる。炭素質フィラーとしては、黒鉛粉末、炭素繊維、カーボンブラック等を使用可能であり、黒鉛粉末及びカーボンブラックの場合は、粒子直径が２０μｍ以下であることが望ましい。また、炭素繊維の場合は、繊維直径が２０μｍ以下で、長さが３ｍｍ以下であることが望ましい。加えて、紙への炭素質フィラーの配合割合は、２質量％〜１２質量％であることが望ましい。炭素質フィラーのサイズが大きい場合、あるいは、紙への炭素質フィラーの配合割合が大きい場合は、紙の組織の緻密性や均一性が低下し、紙に担持される混合溶液が不十分、不均一となり、ひいては、ガス不透過性が低下するおそれがある。一方、紙への炭素質フィラーの配合割合が小さい場合は、製造される炭素薄板の電気伝導性を高める効果を十分に発揮することができない。 In addition, as the paper to be impregnated with the mixed solution, a paper containing a carbonaceous filler obtained by blending a paper raw material with a carbonaceous filler and making paper can be used. As the carbonaceous filler, graphite powder, carbon fiber, carbon black, or the like can be used. In the case of graphite powder and carbon black, the particle diameter is desirably 20 μm or less. In the case of carbon fiber, it is desirable that the fiber diameter is 20 μm or less and the length is 3 mm or less. In addition, the mixing ratio of the carbonaceous filler to the paper is desirably 2% by mass to 12% by mass. If the size of the carbonaceous filler is large, or if the proportion of carbonaceous filler in the paper is large, the denseness and uniformity of the paper structure will be reduced, and the mixed solution carried on the paper will be insufficient or unsatisfactory. There is a possibility that the gas impermeability may be lowered due to uniformity. On the other hand, when the blending ratio of the carbonaceous filler to the paper is small, the effect of increasing the electrical conductivity of the produced carbon thin plate cannot be sufficiently exhibited.
含浸工程で紙に含浸させる混合溶液は、乾性油または乾性油の構成脂肪酸を混合したフェノール樹脂を、有機溶媒に溶解した溶液を使用する。有機溶媒としては、トルエン、アセトン、エタノール等を使用可能である。 As the mixed solution to be impregnated into the paper in the impregnation step, a solution obtained by dissolving a dry oil or a phenol resin mixed with a constituent fatty acid of the dry oil in an organic solvent is used. As the organic solvent, toluene, acetone, ethanol or the like can be used.
また、紙に炭素質フィラーを含有させる場合に代替して、混合溶液に炭素質フィラーを含有させることもできる。この場合の炭素質フィラーとしては、上記と同様に、黒鉛粉末、炭素繊維、カーボンブラック等を使用可能であり、そのサイズは、黒鉛粉末及びカーボンブラックの場合は、粒子直径が２０μｍ以下、炭素繊維の場合は、繊維直径が２０μｍ以下で、長さが３ｍｍ以下であることが望ましい。また、炭素質フィラーを含有する混合溶液としては、混合溶液から揮発分を除去した固形分に対する炭素質フィラーの割合が１質量％〜１１質量％となる混合溶液が望ましい。炭素質フィラーのサイズが大きい場合、紙の表面に付着する炭素質フィラーが増加し、焼成時に剥離しやすくなる。また、混合溶液における炭素質フィラーの割合が大きい場合は、紙に担持された混合溶液中の炭素質フィラー及び樹脂成分の分布がそれぞれ不均一となり易く、ガス不透過性が低下するおそれがある。一方、混合溶液における炭素質フィラーの割合が小さい場合は、製造される炭素薄板の電気伝導性を高める効果を、十分に発揮することができない。 Moreover, it can replace with the case where a paper contains a carbonaceous filler, and can also contain a carbonaceous filler in a mixed solution. As the carbonaceous filler in this case, graphite powder, carbon fiber, carbon black and the like can be used as described above. The size of the graphite powder and carbon black is 20 μm or less in the case of graphite powder and carbon black. In this case, it is desirable that the fiber diameter is 20 μm or less and the length is 3 mm or less. Moreover, as a mixed solution containing a carbonaceous filler, the mixed solution from which the ratio of the carbonaceous filler with respect to solid content which removed the volatile matter from the mixed solution will be 1 mass%-11 mass% is desirable. When the size of the carbonaceous filler is large, the carbonaceous filler adhering to the surface of the paper increases, and it becomes easy to peel off during firing. Moreover, when the ratio of the carbonaceous filler in the mixed solution is large, the distribution of the carbonaceous filler and the resin component in the mixed solution supported on paper is likely to be non-uniform, and the gas impermeability may be reduced. On the other hand, when the ratio of the carbonaceous filler in the mixed solution is small, the effect of increasing the electrical conductivity of the produced carbon thin plate cannot be sufficiently exhibited.
なお、含浸工程では、紙に混合溶液を含浸させる操作に先立ち、紙を加熱乾燥して水分を十分に除去しておくことが望ましい。紙の水分除去が不十分であると、有機溶媒系の混合溶液が紙に含浸しにくいことに加え、紙の気孔に含浸した混合溶液の奥に水分が取り残され、その後に行われる積層圧着工程や炭化工程において、発泡、膨れ、層間剥離などを生じやすいものとなる。紙を乾燥させるための加熱は、１００℃以上で２３０℃を超えない温度で行うことが望ましい。１００℃以下では水分が蒸発しにくく、２３０℃を超えると紙のセルロース繊維が劣化し、最終的に製造される炭素薄板の機械的強度が低下するおそれがある。 In the impregnation step, it is desirable to sufficiently remove moisture by heating and drying the paper prior to the operation of impregnating the paper with the mixed solution. Insufficient water removal from the paper makes it difficult for the organic solvent-based mixed solution to impregnate the paper. In addition, moisture is left behind in the mixed solution impregnated in the pores of the paper, and then the laminated crimping process is performed. In the carbonization process, foaming, swelling, delamination and the like are likely to occur. The heating for drying the paper is desirably performed at a temperature of 100 ° C. or more and not exceeding 230 ° C. If it is 100 ° C. or lower, moisture hardly evaporates, and if it exceeds 230 ° C., the cellulose fibers of the paper are deteriorated, and the mechanical strength of the finally produced carbon sheet may be lowered.
含浸工程を経て得られた含浸紙は、乾燥工程において、１１０℃〜１５０℃の範囲の所定の温度に、一定に保持された乾燥機内で乾燥する。含浸工程における混合溶液の濃度（樹脂濃度）や紙への含浸量により、固形分割合が２５％〜５５％となるように調整すると共に、含浸工程における混合溶液の濃度（有機溶媒濃度）及び乾燥工程における乾燥温度や乾燥時間により、揮発分割合が２．５％〜５．５％となるように調整を行う。 The impregnated paper obtained through the impregnation step is dried in a dryer maintained at a predetermined temperature in the range of 110 ° C. to 150 ° C. in the drying step. Depending on the concentration of the mixed solution (resin concentration) in the impregnation step and the amount of paper impregnation, the solid content ratio is adjusted to 25% to 55%, and the concentration of the mixed solution (organic solvent concentration) in the impregnation step and drying are adjusted. Adjustment is performed so that the volatile content ratio is 2.5% to 5.5% depending on the drying temperature and drying time in the process.
固形分割合及び揮発分割合は、それぞれ以下の式により算出される。ここで、「揮発分」には、乾燥処理後含浸紙を更に加熱処理することにより除去される有機溶媒分、及び、紙に含浸した液中の未反応樹脂の重合反応が更なる加熱処理によって更に進行し、その重合反応の結果生じた水が蒸発する分が含まれる。そこで、以下では、揮発分を乾燥処理後含浸紙から除去する処理を行った後の含浸紙を「揮発分除去後含浸紙」と称する。なお、乾燥処理後含浸紙から揮発分を除去する処理は、乾燥処理後含浸紙を１５０℃で３０分間加熱することにより行うことができる。
固形分割合＝（（揮発分除去後含浸紙の質量）−（紙の質量））×１００／（乾燥処理後含浸紙の質量）
揮発分割合＝（（乾燥処理後含浸紙の質量）−（揮発分除去後含浸紙の質量））×１００／（乾燥処理後含浸紙の質量）
The solid content ratio and the volatile content ratio are calculated by the following equations, respectively. Here, the “volatile matter” includes the organic solvent content that is removed by further heat-treating the impregnated paper after the drying treatment, and the polymerization reaction of the unreacted resin in the liquid impregnated in the paper by further heat treatment. The amount of water that progresses further and vaporizes as a result of the polymerization reaction is included. Therefore, hereinafter, the impregnated paper after the process of removing the volatile matter from the impregnated paper after the drying treatment is referred to as “impregnated paper after the volatile matter removal”. The treatment for removing volatile components from the impregnated paper after drying treatment can be performed by heating the impregnated paper after drying treatment at 150 ° C. for 30 minutes.
Solid content ratio = ((mass of impregnated paper after removal of volatile matter) − (mass of paper)) × 100 / (mass of impregnated paper after drying treatment)
Volatile content ratio = ((mass of impregnated paper after drying treatment) − (mass of impregnated paper after removal of volatile matter)) × 100 / (mass of impregnated paper after drying treatment)
乾燥工程を経た乾燥処理後含浸紙は、積層圧着工程で複数枚を積層し、加熱圧着して積層体とする。加熱温度は、常法に従い、圧着ヘッドの温度をスチーム加熱温度である１３０℃〜１５０℃とすることが好ましい。圧着圧力は、１．５ＭＰａ〜５．０ＭＰａとする。圧力が小さ過ぎれば、積層された含浸紙同士の接着が弱いものとなる一方、圧力が大き過ぎれば積層された含浸紙同士の密着性が高すぎ、後に行われる炭化工程で、樹脂の熱分解により発生するガスがスムーズに排出されにくくなる。 The post-drying impregnated paper that has undergone the drying process is laminated in a laminating and crimping process, and heat-pressed to obtain a laminate. The heating temperature is preferably 130 to 150 ° C., which is the steam heating temperature, according to a conventional method. The pressure bonding pressure is 1.5 MPa to 5.0 MPa. If the pressure is too low, the adhesion between the laminated impregnated papers will be weak, while if the pressure is too high, the adhesion between the laminated impregnated papers will be too high, and the thermal decomposition of the resin will occur in the carbonization step performed later. This makes it difficult to smoothly discharge the gas generated.
炭化工程では、積層圧着工程を経て得られた積層体を、膨張黒鉛シートに挟み込んだ状態で焼成する。このとき、複数の積層体それぞれの間に膨張黒鉛シートを挟んで複数の積層体を積み重ね、更にその全体を外側から黒鉛板で挟んだ状態で、詰め粉に埋設し、焼成することができる。このように、熱伝導率の高い膨張黒鉛シートに積層体を挟み込むことにより、積層体における温度分布が均一化すると共に、滑り性の高い膨張黒鉛シートに沿って積層体が滑らかに収縮するため、積層体の反りや変形が抑制される。更に、複数の積層体全体が黒鉛板に挟み込まれ、詰め粉に埋設された状態で焼成されるため、積層体の反りや変形がより有効に抑制される。 In the carbonization step, the laminate obtained through the laminate pressure bonding step is fired in a state of being sandwiched between expanded graphite sheets. At this time, the plurality of laminates can be stacked by sandwiching an expanded graphite sheet between each of the plurality of laminates, and further, the whole can be embedded in the packing powder and fired in a state of being sandwiched between the graphite plates from the outside. Thus, by sandwiching the laminate in the expanded graphite sheet having a high thermal conductivity, the temperature distribution in the laminate becomes uniform, and the laminate smoothly contracts along the expanded graphite sheet having a high slip property. Warpage and deformation of the laminate are suppressed. Furthermore, since the whole several laminated body is pinched | interposed into the graphite board and baked in the state embedded in the filling powder, the curvature and deformation | transformation of a laminated body are suppressed more effectively.
炭化工程における焼成は、非酸化性雰囲気に保持した電気炉内で、常温から８００℃まで昇温することにより行う。昇温速度は小さい方が樹脂の熱分解が穏やかとなり、発泡や膨れによる不良品の発生率が低下する一方、昇温速度が小さ過ぎれば、焼成のための所要時間（日数）が長く炭素薄板の製造効率が悪い。 Firing in the carbonization step is performed by raising the temperature from room temperature to 800 ° C. in an electric furnace maintained in a non-oxidizing atmosphere. The lower the temperature increase rate, the more the thermal decomposition of the resin becomes milder, and the incidence of defective products due to foaming and swelling decreases. On the other hand, if the temperature increase rate is too small, the time required for firing (days) is longer and the carbon thin plate The production efficiency is poor.
含浸工程〜炭化工程を経て製造される非晶質炭素からなる炭素薄板は、後述の実施例に示すように、厚さ１．７ｍｍ〜２．４ｍｍと、従来の炭素薄板より厚さが大きいにも関わらず、従来の炭素薄板と同程度以上のガス不透過性を備えている。 The carbon thin plate made of amorphous carbon manufactured through the impregnation step to the carbonization step has a thickness of 1.7 mm to 2.4 mm, which is larger than that of the conventional carbon thin plate, as shown in Examples described later. Nevertheless, it has a gas impermeability equivalent to or higher than that of conventional carbon thin plates.
次に、第二実施形態の製造方法について説明する。第二実施形態の製造方法は、炭化工程までは第一実施形態の製造方法と同様であり、炭化工程の後に、炭化した積層体を非酸化性雰囲気で１７００℃〜２３００℃で焼成し黒鉛化させる黒鉛化工程を具備している。 Next, the manufacturing method of 2nd embodiment is demonstrated. The production method of the second embodiment is the same as the production method of the first embodiment until the carbonization step, and after the carbonization step, the carbonized laminate is calcined at 1700 ° C. to 2300 ° C. in a non-oxidizing atmosphere. The graphitization process is carried out.
黒鉛化工程では、炭化工程を経て得られた非晶質炭素からなる炭素薄板を、数枚〜１０枚程度積み重ねて膨張黒鉛シートで挟み込む。これを一単位として、複数単位を積層し、全体を炭素板で挟み込んだ状態で、詰め粉に埋設し、焼成する。非晶質炭素となった炭素薄板は、炭化前の積層体に比べて高い熱伝導性を有するため、炭素薄板一枚ごとに黒鉛シートで挟み込むことまではしなくても、反りや変形を防止して、黒鉛化した炭素薄板を収率良く製造することができる。 In the graphitization step, several to ten carbon thin plates made of amorphous carbon obtained through the carbonization step are stacked and sandwiched between expanded graphite sheets. With this as a unit, a plurality of units are laminated, and the whole is sandwiched between carbon plates, embedded in packing powder, and fired. The carbon thin plate that has become amorphous carbon has higher thermal conductivity than the laminate before carbonization, so it can be prevented from warping and deformation without having to be sandwiched between graphite sheets. Thus, a graphitized carbon sheet can be produced with high yield.
黒鉛化工程における焼成は、非酸化性雰囲気に保持したアチソン炉などの電気炉内で、数時間から数十時間をかけて１７００℃〜２３００℃の範囲内の所定温度まで昇温して行う。焼成温度が２３００℃を超えると、黒鉛の結晶が異常成長し、組織がポーラスとなってガス不透過性が低下するおそれがある。また、黒鉛の結晶における異方性に起因して、層間剥離が生じ易くなり、収率が低下するおそれがある。 Firing in the graphitization step is performed by raising the temperature to a predetermined temperature within a range of 1700 ° C. to 2300 ° C. over several hours to several tens of hours in an electric furnace such as an Atchison furnace held in a non-oxidizing atmosphere. If the firing temperature exceeds 2300 ° C., graphite crystals grow abnormally, the structure becomes porous, and gas impermeability may be reduced. Further, due to the anisotropy in the graphite crystals, delamination is likely to occur, and the yield may be reduced.
含浸工程〜黒鉛化工程を経て製造される黒鉛化した炭素薄板は、上述のように厚さが大きいと共に、後述のように、高い電気伝導性を備えると共に、実用的なガス不透過性を備えている。 The graphitized carbon sheet produced through the impregnation step to the graphitization step has a large thickness as described above, and has a high electric conductivity and a practical gas impermeability as described later. ing.
次に、本実施形態の製造方法の条件を上記のように定めた根拠について、具体的な検討結果を示して説明する。検討は、以下に示す３６種類の試料を用いて行った。 Next, the grounds for defining the conditions of the manufacturing method of the present embodiment as described above will be described with specific examination results. The examination was performed using the following 36 types of samples.
試料１〜試料２０では、紙として、クラフト・リンタ混抄紙（王子製紙製、米坪１００ｇ／ｍ２）を使用した。試料２１〜試料３６では、木材パルプ、水、及び、黒鉛粉末を含有する抄紙用の原液を調製後、丸網抄紙機を使用して、上記のクラフト・リンタ混抄紙と同程度の米坪１００ｇ／ｍ２〜１２０ｇ／ｍ２の黒鉛粉混抄紙を抄紙した。黒鉛粉末としては、高炉レンガ用の人工黒鉛を平均粒子径１４μｍに粉砕したものを使用した。黒鉛粉混抄紙に対する黒鉛粉末の割合は、２質量％、５質量％、８質量％、１２質量％、１４質量％の５種類とした。ここで、黒鉛粉混抄紙に対する黒鉛の割合は、次式により算出した。
（黒鉛粉末の質量）×１００／（（針葉樹クラフトパルプ（ＮＫＰ）の質量）＋（黒鉛粉末の質量）＋（アクリル系凝集剤の質量））
なお、黒鉛粉末の割合によらず、アクリル系凝集剤の割合は黒鉛粉混抄紙の３質量％とした。
In Samples 1 to 20, Kraft / Linter mixed paper (made by Oji Paper Co., Ltd., 100 g / m 2 ) was used as the paper. In Samples 21 to 36, after preparing a papermaking stock solution containing wood pulp, water, and graphite powder, a round net paper machine was used, and 100 g of rice basis weight was the same as the above Kraft / Linter mixed paper. Paper made of graphite powder mixed paper of / m 2 to 120 g / m 2 was made. As the graphite powder, pulverized artificial graphite for blast furnace bricks having an average particle diameter of 14 μm was used. The ratio of the graphite powder to the graphite powder mixed paper was 5 mass%, 5 mass%, 8 mass%, 12 mass%, and 14 mass%. Here, the ratio of graphite to the graphite powder mixed paper was calculated by the following formula.
(Mass of graphite powder) × 100 / ((mass of softwood kraft pulp (NKP)) + (mass of graphite powder) + (mass of acrylic flocculant))
The proportion of the acrylic flocculant was 3% by mass of the graphite powder mixed paper regardless of the proportion of the graphite powder.
クラフト・リンタ混抄紙、黒鉛粉混抄紙ともに、３００ｍｍ×３００ｍｍに裁断した。裁断された紙を、２３０℃で加熱し水分を十分に除去した。 Both kraft / linter mixed paper and graphite powder mixed paper were cut into 300 mm × 300 mm. The cut paper was heated at 230 ° C. to sufficiently remove moisture.
紙に含浸させる混合溶液（乾性油または乾性油の構成脂肪酸を混合したフェノール樹脂を含む混合溶液）としては、桐油とフェノールを混合してからホルマリンを加えて反応を進行させて得られた桐油変性フェノール樹脂を、トルエンで希釈して調製した。紙としてクラフト・リンタ混抄紙を使用した試料の内の試料１〜試料４、及び、紙として黒鉛粉混抄紙を使用した試料２１〜試料２６では、上記のように調製された混合溶液を、そのままの状態で含浸させた（含浸工程）。 As a mixed solution to be impregnated into paper (drying oil or a mixed solution containing a phenolic resin mixed with constituent fatty acids of drying oil), tung oil modified with tung oil and phenol, then added with formalin to proceed with the reaction A phenolic resin was prepared by diluting with toluene. Samples 1 to 4 out of samples using Kraft / Linter mixed paper as paper and Samples 21 to 26 using graphite powder mixed paper as paper, the mixed solutions prepared as described above were used as they were. In the state of (impregnation step).
一方、試料５〜試料２０については、上記のように調製された混合溶液に黒鉛粉末を混合した混合溶液を含浸させた（含浸工程）。黒鉛粉末としては、上記と同一のもの（高炉レンガ用の人工黒鉛を平均粒子径１４μｍに粉砕した粉末）を使用した。混合溶液中の黒鉛粉末の割合は、混合溶液から揮発分を除去した固形分に対する黒鉛粉末の割合が１質量％、３質量％、８質量％、１１質量％、１３質量％となる５種類とした。ここで、混合溶液から揮発分を除去した固形分に対する黒鉛粉末の割合（質量％）は、次式により算出した。
（混合溶液５０ｍｌ中の黒鉛粉末の質量）×１００／（混合溶液５０ｍｌを１５０℃で１時間加熱した後の残存分の質量）
On the other hand, for Sample 5 to Sample 20, the mixed solution prepared as described above was impregnated with a mixed solution obtained by mixing graphite powder (impregnation step). As the graphite powder, the same powder as above (powder obtained by pulverizing artificial graphite for blast furnace bricks to an average particle diameter of 14 μm) was used. The ratio of the graphite powder in the mixed solution is 5 types in which the ratio of the graphite powder to the solid content obtained by removing the volatile component from the mixed solution is 1% by mass, 3% by mass, 8% by mass, 11% by mass, and 13% by mass. did. Here, the ratio (mass%) of the graphite powder with respect to solid content which removed the volatile matter from the mixed solution was computed by following Formula.
(Mass of graphite powder in 50 ml of mixed solution) × 100 / (Mass of residual after heating 50 ml of mixed solution at 150 ° C. for 1 hour)
混合溶液を含浸させた含浸紙は、１３０℃に保持された乾燥機内で乾燥した（乾燥工程）。混合溶液の濃度、乾燥時間等の調整により、固形分割合、及び、揮発分割合の異なる試料を調製した。 The impregnated paper impregnated with the mixed solution was dried in a dryer maintained at 130 ° C. (drying process). Samples with different solid content ratios and volatile content ratios were prepared by adjusting the concentration of the mixed solution, the drying time, and the like.
乾燥処理後含浸紙を１５枚〜２６枚積層し、１５０℃の温度下で３０分、所定の圧力で加圧し圧着して、厚さ２．６ｍｍ〜３．７ｍｍの積層体とした（積層圧着工程）。 After the drying treatment, 15 to 26 impregnated papers were laminated, pressed at a predetermined pressure for 30 minutes at a temperature of 150 ° C., and pressed to form a laminated body having a thickness of 2.6 mm to 3.7 mm (laminated pressure bonding). Process).
試料ごとに、紙の種類、黒鉛を添加した試料はその割合、固形分割合、揮発分割合、積層枚数、圧着圧力、及び、成形された積層体の厚さを、表１にまとめて示す。 For each sample, Table 1 summarizes the type of paper, the sample added with graphite, the ratio, the solid content ratio, the volatile content ratio, the number of stacked layers, the pressure of pressure bonding, and the thickness of the molded laminate.
各試料について、積層体と膨張黒鉛シートを交互に重ねて積層体１０個を積み重ね、更にその全体を、厚さ５ｍｍの一対の黒鉛板で挟み、詰め粉に埋設した。その状態で約５ｇ／ｃｍ２の荷重をかけ、電気炉内に静置し、非酸化性雰囲気で常温から８００℃まで加熱した（炭化工程）。昇温速度については、３．２℃／ｈｒと、３．６℃／ｈｒの二種類とした。ここで、膨張黒鉛シートとしては、ＴＹＫ製グラファイトシート、厚さ０．８ｍｍを使用した。 About each sample, a laminated body and an expanded graphite sheet were piled up alternately, 10 laminated bodies were piled up, and also the whole was pinched | interposed with a pair of graphite plate of thickness 5mm, and was embed | buried in the stuffing powder. In this state, a load of about 5 g / cm 2 was applied, left in an electric furnace, and heated from normal temperature to 800 ° C. in a non-oxidizing atmosphere (carbonization step). Regarding the rate of temperature increase, two types of 3.2 ° C./hr and 3.6 ° C./hr were used. Here, as the expanded graphite sheet, a TYK graphite sheet having a thickness of 0.8 mm was used.
また、対比のために、膨張黒鉛シートに代替して厚さ５ｍｍの黒鉛板を使用し、積層体と黒鉛板を交互に重ねて積層体１０個を積み重ね、更にその全体を、厚さ５ｍｍの一対の黒鉛板で挟み、その状態で詰め粉に埋設した試料についても、同じ荷重をかけ、昇温速度３．２℃／ｈｒで常温から８００℃まで加熱し焼成した。 For comparison, a graphite plate having a thickness of 5 mm is used instead of the expanded graphite sheet, and the laminate and the graphite plate are alternately stacked to stack 10 laminates. A sample sandwiched between a pair of graphite plates and embedded in the stuffed powder in that state was also subjected to the same load, heated from room temperature to 800 ° C. at a temperature rising rate of 3.2 ° C./hr, and fired.
炭化工程における積層体の挟み込みの態様、及び、昇温速度条件が相違する場合のそれぞれについて、焼成後に冷却した電気炉から取出した炭素薄板の外観を肉眼で観察し、反り、膨れ、剥離、亀裂等の発生のない良品の枚数を計数した。すなわち、炭化工程における、三つの条件Ａ，Ｂ，Ｃの対比である。対比の結果を表２に示す。
条件Ａ：積層体を膨張黒鉛シートで挟む、昇温速度３．２℃／ｈｒ
条件Ｂ：積層体を膨張黒鉛シートで挟む、昇温速度３．６℃／ｈｒ
条件Ｃ：積層体を黒鉛板で挟む、昇温速度３．２℃／ｈｒ
The appearance of the carbon thin plate taken out from the electric furnace cooled after firing was observed with the naked eye for each of the sandwiched state in the carbonization process and the case where the temperature increase rate conditions were different, and warped, swollen, separated, cracked. The number of non-defective products that did not occur was counted. That is, the comparison of the three conditions A, B, and C in the carbonization process. The comparison results are shown in Table 2.
Condition A: The laminate is sandwiched between expanded graphite sheets, and the temperature rise rate is 3.2 ° C./hr.
Condition B: Laminate is sandwiched between expanded graphite sheets, heating rate 3.6 ° C./hr
Condition C: The laminate is sandwiched between graphite plates, and the heating rate is 3.2 ° C./hr.
試料１，３，５〜８，２４，２６，２８，２９では、何れの場合も全数が外観上良品であった。一方、試料１１，１４，２０，３１，３６は、それぞれ全数に反り、膨れ、剥離、亀裂等の不良が発生した。条件によって良品の数が相違するその他の試料について、積層体を膨張黒鉛シート間に挟んだ点で同一条件であって、昇温速度の条件のみが相違する場合を比較すると（条件ＡとＢとの対比）、昇温速度が小さい方（条件Ａ）が良品の数が多い傾向があり、昇温速度の条件は同一であって積層体間の材料が膨張黒鉛シートか黒鉛板かで相違する場合を比較すると（条件ＡとＣとの対比）、積層体間の材料が膨張黒鉛シートの方（条件Ａ）が、良品の数が多かった。以上より、積層体を膨張黒鉛シート間に挟み、３．２℃／ｈｒ程度の昇温速度で焼成することにより、外観が良好な炭素薄板を高い収率で製造できると考えられた。また、昇温速度は３．２℃／ｈｒ〜３．６℃／ｈｒの範囲であれば、炭素薄板の収率、製造効率ともに実用的な範囲内であと考えられた。 Samples 1, 3, 5 to 8, 24, 26, 28, and 29 were all good in appearance in all cases. On the other hand, Samples 11, 14, 20, 31, and 36 warped in total, and defects such as swelling, peeling, and cracking occurred. For other samples with different numbers of non-defective products depending on the conditions, a comparison was made between the case where the laminate was sandwiched between the expanded graphite sheets and the same conditions and only the temperature increase rate was different (conditions A and B). ), The one with a lower temperature increase rate (Condition A) tends to have more non-defective products, the temperature increase rate conditions are the same, and the material between the laminates differs depending on whether it is an expanded graphite sheet or a graphite plate. When the cases were compared (contrast between conditions A and C), the number of non-defective products was larger when the material between the laminates was an expanded graphite sheet (condition A). From the above, it was considered that a carbon thin plate having a good appearance can be produced in a high yield by sandwiching the laminate between expanded graphite sheets and firing at a temperature rising rate of about 3.2 ° C./hr. Moreover, if the rate of temperature increase was in the range of 3.2 ° C./hr to 3.6 ° C./hr, it was considered that both the yield and production efficiency of the carbon thin plate were within a practical range.
最も良品の割合が高かった条件Ａによる炭化工程を経て得られた炭素薄板について、厚さを測定すると共に、ガス透過度、電気比抵抗、及び、三点曲げ強さについて、次の方法で試験を行った。ここで、ガス透過度は、石鹸膜流量計を用い、単位時間当たりの窒素ガスの透過量を、差圧０．１ＭＰａの条件下で測定した。また、電気比抵抗は、炭素薄板から２０ｍｍ幅の短冊状の試験片を切り出し、電極間距離５０ｍｍ、電流１Ａのときの電圧値より算出した。また、三点曲げ強さは、炭素薄板から２０ｍｍ幅の短冊状の試験片を切り出し、支点間距離２０ｍｍ、クロスヘッドスピード１．５ｍｍ／ｍｉｎの条件で測定した。何れの試験も、２０℃±３℃に保持された環境で行った。また、何れの試験も、三つの試験片について測定を行い、その平均値を算出した。上記の測定結果を、表１にあわせて示す。 The carbon thin plate obtained through the carbonization process under the condition A with the highest percentage of good products was measured for thickness, gas permeability, electrical resistivity, and three-point bending strength by the following methods. Went. Here, the gas permeability was measured by using a soap film flow meter and measuring the nitrogen gas permeation amount per unit time under a differential pressure of 0.1 MPa. The electrical specific resistance was calculated from a voltage value when a strip-shaped test piece having a width of 20 mm was cut out from a carbon thin plate and the distance between the electrodes was 50 mm and the current was 1A. Further, the three-point bending strength was measured by cutting a strip-shaped test piece having a width of 20 mm from a carbon thin plate, and having a distance between supporting points of 20 mm and a crosshead speed of 1.5 mm / min. All tests were conducted in an environment maintained at 20 ° C. ± 3 ° C. In each test, three test pieces were measured and the average value was calculated. The measurement results are shown in Table 1.
表１から明らかなように、全数が外観上の不良品であった試料１１，１４，２０，３１，３６を除き、何れの試料についても、従来の炭素薄板より厚さの大きい、厚さ１．７ｍｍ〜２．４ｍｍの炭素薄板が得られた。 As is clear from Table 1, all samples except the samples 11, 14, 20, 31, and 36, which were defective in appearance, were thicker than the conventional carbon thin plate. Carbon thin plates of 0.7 mm to 2.4 mm were obtained.
ただし、試料２６は、測定した物性値のうちガス不透過性が不十分であった。それ以外の試料１〜１０，１２，１３，１５〜１９，２１〜２５，２７〜３０，３２〜３５では、窒素ガス透過度は２×１０−１２ｃｃ／ｃｍ２・ｓｅｃ〜４×１０−７ｃｃ／ｃｍ２・ｓｅｃであり、従来の炭素薄板と同程度の優れたガス不透過性を有しており、且つ、電気比抵抗も１．８×１０−３Ω・ｃｍ〜５．３×１０−３Ω・ｃｍであり、従来の炭素薄板の電気比抵抗と同程度であった。加えて、三点曲げ強さも９９ＭＰａ〜１５１ＭＰａと、実用的な範囲であった。 However, the sample 26 had insufficient gas impermeability among the measured physical property values. In other samples 1 to 10, 12 , 13, 15 to 19, 21 to 25, 27 to 30, and 32 to 35, the nitrogen gas permeability is 2 × 10 −12 cc / cm 2 · sec to 4 × 10 −. 7 cc / cm 2 · sec, excellent gas impermeability comparable to that of conventional carbon thin plates, and electrical resistivity of 1.8 × 10 −3 Ω · cm to 5.3 × 10 −3 Ω · cm, which is similar to the electrical specific resistance of the conventional carbon thin plate. In addition, the three-point bending strength was also in a practical range of 99 MPa to 151 MPa.
以上の結果から、全数が外観上の不良品であった試料１１，１４，２０，３１，３６、及び、物性値が不十分であった試料２６が除外されて良品のみが製造できる条件を検討した結果、以下の条件が抽出された。
紙または含浸させる混合溶液に炭素を含有させない場合：
固形分割合＝２５質量％〜５５質量％、且つ
揮発分割合＝２．５質量％〜５．５質量％
From the above results, the samples 11, 14, 20, 31, and 36, all of which were defective in appearance, and the sample 26 that had insufficient physical properties were excluded, and the conditions under which only good products could be manufactured were examined. As a result, the following conditions were extracted.
When carbon is not included in the paper or mixed solution to be impregnated:
Solid content ratio = 25 mass% to 55 mass%, and volatile content ratio = 2.5 mass% to 5.5 mass%
また、紙または含浸させる混合溶液に炭素を含有させる場合、良品のみが製造されるために、上記範囲の固形分割合及び揮発分割合に加えて備えるべき条件として、以下の条件が抽出された。
紙の場合：紙に対する黒鉛粉末の割合＝２質量％〜１２質量％
混合溶液の場合：混合溶液から揮発分を除去した固形分に対する黒鉛粉末の割合＝１質量％〜１１質量％
In addition, when carbon is included in the paper or the mixed solution to be impregnated, only good products are produced. Therefore, the following conditions were extracted as conditions to be provided in addition to the solid content ratio and the volatile content ratio in the above ranges.
In the case of paper: ratio of graphite powder to paper = 2 mass% to 12 mass%
In the case of a mixed solution: ratio of graphite powder to solid content obtained by removing volatile components from the mixed solution = 1 mass% to 11 mass%
次に、良品の非晶質炭素薄板（試料１〜１０，１２，１３，１５〜１９，２１〜２５，２７〜３０，３２〜３５）を、黒鉛化した。この工程では、良品の炭素薄板３枚を１枚ずつ膨張黒鉛シート間に挟んで積み重ね、更にその全体を一対の厚さ５ｍｍの黒鉛板で挟み、アチソン式黒鉛化炉にて加熱した（黒鉛化工程）。加熱温度は２３００℃及び２５００℃の二種類とし、常温からそれぞれ１３時間及び１５時間かけて昇温し黒鉛化した。なお、炉内温度は放射温度計で測定した。 Next, non-defective amorphous carbon thin plates (samples 1 to 10, 12, 13, 15 to 19, 21 to 25, 27 to 30, and 32 to 35) were graphitized. In this process, three non-defective carbon thin plates are stacked one by one between expanded graphite sheets, and the whole is further sandwiched between a pair of graphite plates having a thickness of 5 mm and heated in an Atchison-type graphitization furnace (graphitization). Process). There were two heating temperatures of 2300 ° C. and 2500 ° C., and the temperature was raised from normal temperature over 13 hours and 15 hours, respectively, and graphitized. The furnace temperature was measured with a radiation thermometer.
焼成後に冷却した炉から取出した黒鉛化した炭素薄板の外観を肉眼で観察し、反り、膨れ、剥離、亀裂等の発生の有無を観察した。その結果、焼成温度が２３００℃であった場合は、全数が外観上で良品であった。一方、焼成温度が２５００℃であった場合は、全数に亀裂や割れ生じていた。 The appearance of the graphitized carbon thin plate taken out from the furnace cooled after firing was observed with the naked eye, and the presence or absence of warpage, blistering, peeling, cracking, etc. was observed. As a result, when the firing temperature was 2300 ° C., the total number was good in appearance. On the other hand, when the firing temperature was 2500 ° C., cracks or cracks occurred in the whole number.
次に、黒鉛化した炭素薄板の良品（２３００℃焼成）について、上記と同様の方法で、窒素ガス透過度、電気比抵抗、及び、三点曲げ強さの測定を行った。上記の測定結果及び黒鉛化した炭素薄板の厚さの測定結果を、表３に示す。 Next, the non-defective graphitized carbon sheet (fired at 2300 ° C.) was measured for nitrogen gas permeability, electrical resistivity, and three-point bending strength in the same manner as described above. Table 3 shows the measurement results and the thickness measurement results of the graphitized carbon sheet.
表３を表１と対比すると明らかなように、電気比抵抗は１．２×１０−３Ω・ｃｍ〜３．６×１０−３Ω・ｃｍであり、黒鉛化した試料の全てにおいて、電気比抵抗が非晶質炭素（炭化工程後、黒鉛化工程前）のときに比べて小さくなっていた。すなわち、黒鉛化によって電気伝導性が高くなった。一方、ガス不透過性については、黒鉛化によって低下する傾向が見られたが、それでも従来の炭素薄板と同程度のガス不透過性を有していた（窒素ガス透過度として、２×１０−１１ｃｃ／ｃｍ２・ｓｅｃ〜８×１０−７ｃｃ／ｃｍ２・ｓｅｃ）。また、三点曲げ強さについても、黒鉛化によって僅かに低下する傾向が見られたが、それでも９２ＭＰａ〜１４０ＭＰａと実用的な範囲であった。 Table 3 As seen from the comparison between Table 1, the electrical resistivity is 1.2 × 10 -3 Ω · cm~3.6 × 10 -3 Ω · cm, in all graphitized samples, electrical The specific resistance was smaller than that of amorphous carbon (after the carbonization process and before the graphitization process). That is, the electrical conductivity increased by graphitization. On the other hand, the gas for the impermeable, as it tended to decrease by graphitization, but still had a gas impermeable comparable to conventional carbon thin (nitrogen gas permeability, 2 × 10 - 11 cc / cm 2 · sec~8 × 10 -7 cc / cm 2 · sec). Further, the three-point bending strength tended to decrease slightly due to graphitization, but was still in a practical range of 92 MPa to 140 MPa.
なお、炭化工程の後に全数が外観上良品であった試料１，３，５〜８，２４，２８，２９について、３枚の炭素薄板（非晶質炭素）を、膨張黒鉛シート間に挟むことなく積み重ねて２３００℃で焼成したところ、何れの試料もほぼ全数について、外観上良品の黒鉛化した炭素薄板が得られた。このことから、焼成時に膨張黒鉛シート間に挟むことにより反りや膨れ等の変形が抑制される作用は、黒鉛化工程よりも炭化工程において、より重要であると考えられた。 For samples 1, 3, 5-8, 24, 28, and 29, all of which were good in appearance after the carbonization step, three carbon thin plates (amorphous carbon) were sandwiched between the expanded graphite sheets. When they were stacked and fired at 2300 ° C., almost all of the samples were graphitized carbon thin plates with good appearance. From this, it was considered that the action of suppressing deformation such as warpage and swelling by sandwiching between the expanded graphite sheets during firing is more important in the carbonization process than in the graphitization process.
以上、本発明について好適な実施形態を挙げて説明したが、本発明は上記の実施形態に限定されるものではなく、本発明の要旨を逸脱しない範囲において、種々の改良及び設計の変更が可能である。 Although the present invention has been described with reference to the preferred embodiments, the present invention is not limited to the above-described embodiments, and various improvements and design changes can be made without departing from the scope of the present invention. It is.
Claims (8)
前記含浸紙を乾燥させ、乾燥処理後含浸紙とする乾燥工程と、
前記乾燥処理後含浸紙の複数枚を積層し圧着して積層体を得る積層圧着工程と、
前記積層体を非酸化性雰囲気で焼成し炭化させる炭化工程とを具備し、
前記乾燥工程は、前記乾燥処理後含浸紙の質量から揮発分及び前記紙の質量を除いた固形分の質量の前記乾燥処理後含浸紙の質量に対する割合が２５％〜５５％で、且つ、揮発分の質量の前記乾燥処理後含浸紙の質量に対する割合が２．５％〜５．５％となるように行われる
ことを特徴とする緻密質炭素薄板の製造方法。 Impregnation step of impregnating paper made of cellulose fiber with a mixed solution containing a phenolic resin mixed with a dry oil or a constituent fatty acid of a dry oil to obtain an impregnated paper;
Drying the impregnated paper and making it impregnated paper after drying treatment;
A lamination pressure bonding step of laminating a plurality of impregnated papers after the drying treatment and pressing to obtain a laminate;
A carbonization step of firing and carbonizing the laminate in a non-oxidizing atmosphere,
In the drying step, the ratio of the mass of the solid content obtained by removing the volatile content and the mass of the paper from the mass of the impregnated paper after the drying treatment to the mass of the impregnated paper after the drying treatment is 25% to 55%, and the volatilization is performed. A method for producing a dense carbon thin plate, wherein the ratio of the mass of the minute to the mass of the impregnated paper after the drying treatment is 2.5% to 5.5%.
ことを特徴とする請求項１に記載の緻密質炭素薄板の製造方法。 The method for producing a dense carbon thin plate according to claim 1, wherein the lamination pressure bonding step is performed at a pressure of 1.5 MPa to 5.0 MPa.
ことを特徴とする請求項１または請求項２に記載の緻密質炭素薄板の製造方法。 The method for producing a dense carbon thin plate according to claim 1, wherein the carbonization step is performed at a temperature rising rate of 3.2 ° C./hr or more.
ことを特徴とする請求項１乃至請求項３の何れか一つに記載の炭素薄板の製造方法。 The method for producing a carbon thin plate according to any one of claims 1 to 3, wherein the carbonization step is performed in a state where the laminate is sandwiched between graphite sheets.
ことを特徴とする請求項１乃至請求項４の何れか一つに記載の炭素薄板の製造方法。 In the impregnation step, a paper containing 2% by mass to 12% by mass of a carbonaceous filler is used as the paper, or the ratio of the carbonaceous filler to the solid content obtained by removing volatile components from the mixed solution is 1% by mass. It is performed using the said mixed solution containing a carbonaceous filler used as -11 mass%, The manufacturing method of the carbon thin plate as described in any one of Claim 1 thru | or 4 characterized by the above-mentioned.
ことを特徴とする請求項１乃至請求項５の何れか一つに記載の炭素薄板の製造方法。 6. The method according to claim 1, further comprising a graphitization step of baking and graphitizing the carbonized laminate at 1700 ° C. to 2300 ° C. in a non-oxidizing atmosphere after the carbonization step. The manufacturing method of the carbon thin plate as described in one.
窒素ガス透過度が２×１０−１２ｃｃ／ｃｍ２・ｓｅｃ〜４×１０−７ｃｃ／ｃｍ２・ｓｅｃで、厚さが０．５ｍｍ〜２．４ｍｍであることを特徴とする炭素薄板。 A carbon thin plate of amorphous carbon,
A carbon thin plate having a nitrogen gas permeability of 2 × 10 −12 cc / cm 2 · sec to 4 × 10 −7 cc / cm 2 · sec and a thickness of 0.5 mm to 2.4 mm.
窒素ガス透過度が２×１０−１１ｃｃ／ｃｍ２・ｓｅｃ〜８×１０−７ｃｃ／ｃｍ２・ｓｅｃで、厚さが０．４ｍｍ〜２．３ｍｍであることを特徴とする炭素薄板。 A graphitized carbon sheet,
Nitrogen gas permeability at 2 × 10 -11 cc / cm 2 · sec~8 × 10 -7 cc / cm 2 · sec, the carbon sheet, wherein the thickness is 0.4Mm～2.3Mm.
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| JPS62105910A (en) * | 1985-11-05 | 1987-05-16 | Toyo Carbon Kk | Laminated carbon material |
| JPH02199010A (en) * | 1989-01-26 | 1990-08-07 | Kawasaki Steel Corp | Production of thin sheetlike carbon material |
| JPH03277538A (en) * | 1990-03-27 | 1991-12-09 | Osaka Gas Co Ltd | Heat insulating material |
| JPH04182307A (en) * | 1990-11-16 | 1992-06-29 | Tokai Carbon Co Ltd | Production of vetreous carbon material |
| JPH1059782A (en) * | 1996-08-19 | 1998-03-03 | Showa Denko Kk | Production of carbon formed body |
| JPH10277933A (en) * | 1997-03-31 | 1998-10-20 | Shin Kobe Electric Mach Co Ltd | Laminated plate for holding material to be polished |
| JPH11267651A (en) * | 1998-03-24 | 1999-10-05 | Tokai Carbon Co Ltd | Porous carbon electrode for water treatment |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62105910A (en) * | 1985-11-05 | 1987-05-16 | Toyo Carbon Kk | Laminated carbon material |
| JPH02199010A (en) * | 1989-01-26 | 1990-08-07 | Kawasaki Steel Corp | Production of thin sheetlike carbon material |
| JPH03277538A (en) * | 1990-03-27 | 1991-12-09 | Osaka Gas Co Ltd | Heat insulating material |
| JPH04182307A (en) * | 1990-11-16 | 1992-06-29 | Tokai Carbon Co Ltd | Production of vetreous carbon material |
| JPH1059782A (en) * | 1996-08-19 | 1998-03-03 | Showa Denko Kk | Production of carbon formed body |
| JPH10277933A (en) * | 1997-03-31 | 1998-10-20 | Shin Kobe Electric Mach Co Ltd | Laminated plate for holding material to be polished |
| JPH11267651A (en) * | 1998-03-24 | 1999-10-05 | Tokai Carbon Co Ltd | Porous carbon electrode for water treatment |
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