JPH06135779A - Production of hollow graphite molded body - Google Patents

Abstract

PURPOSE:To easily obtain a hollow graphite molded product which can be easily handled by arranging a granular thermoplastic resin into which a heat- resistant material is preliminarily incorporated in a graphite powder and them melting and carbonizing the granular material. CONSTITUTION:A heat-resistant material is incorporated into a granular thermoplastic resin. For example, the heat-resistant material is coated with the thermoplastic resin powder, or a dispersion mixture of the heat-resistant resin and thermoplastic resin powder is prepared in a granular state and then as necessary, the thermoplastic resin powder is applied onto the surface of the granular material. This granular material is disposed in a graphite powder and is given the insolubilization treatment at 250-350 deg.C in an oxidative atmosphere, and then fired in a nonoxidative atmosphere to the temp. at which the granular material is carbonized. Thus, the granular is molten and carbonized to obtain a hollow graphite molded product including activated carbon.

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、中空状黒鉛成形物の製
造方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a hollow graphite molding.

【０００２】[0002]

【従来の技術とその課題】黒鉛粉末は、耐熱性や耐薬品
性に優れ、中でも天然黒鉛は、結晶性にも優れているた
め、耐熱性や耐薬品性及び潤滑性が要求される固体潤滑
材や、導電性を向上させる導電性フィラ−などとして用
いられているが、微細で軽量の粉末であるため、取り扱
い性が悪く、粉塵公害等の原因にもなっている。BACKGROUND OF THE INVENTION Graphite powder is excellent in heat resistance and chemical resistance, and natural graphite is excellent in crystallinity. Therefore, solid lubrication which requires heat resistance, chemical resistance and lubricity. It is used as a material and as a conductive filler for improving conductivity, but since it is a fine and lightweight powder, it is difficult to handle and causes dust pollution.

【０００３】これに対し、黒鉛粉末の取り扱い性を良く
するために、黒鉛粉末を合成樹脂、ワックス、金属等で
表面処理する方法や、バインダ−を加えて顆粒状にする
製造方法なども知られている。しかし、これらの方法に
おいては、複雑な製造工程が必要となる。On the other hand, in order to improve the handleability of the graphite powder, a method of surface-treating the graphite powder with a synthetic resin, a wax, a metal or the like, or a manufacturing method of adding a binder to form a granule is known. ing. However, these methods require complicated manufacturing steps.

【０００４】そこで、本出願人は、複雑な製造工程を必
要とせずに、しかも、取り扱い性の良好な中空状黒鉛成
形物を製造する方法について、先に一つの提案をした
（特願平３−３５９１３０号）。熱可塑性樹脂の粒子状
物質と黒鉛粉末とを使用し、粒子状物質を黒鉛粉末中に
配置させた後、粒子状物質を溶融・炭化させることによ
り中空状黒鉛成形物を製造するというものである。ここ
で、単なる黒鉛粉末の集合粒子状物ではなく中空状の成
形物になるのは、溶融した粒子状物質に黒鉛粉末が入り
込んでいくのではなく、溶融した粒子状物質が黒鉛粉末
（集合物）相互の隙間に浸透していくことによると推察
される。Therefore, the applicant of the present invention has previously proposed one method for producing a hollow graphite molded product which does not require a complicated production process and has good handleability (Japanese Patent Application No. Hei 3 (1999) -311). -359130). Using a thermoplastic resin particulate material and graphite powder, the particulate material is placed in the graphite powder, and then the particulate material is melted and carbonized to produce a hollow graphite molded article. . Here, the hollow molded article is not a mere aggregated particle of graphite powder, but the fact that the graphite powder does not enter into the molten particulate matter, but the molten particulate matter is the graphite powder (aggregate ) It is presumed that this is due to penetration into the mutual gap.

【０００５】本発明は、上記提案を更に発展させ、得ら
れる黒鉛成形物の中空状形状を利用して内部に適宜の耐
熱性材料を含有させることにより、この耐熱性材料の機
能をも発揮させようとするものである。The present invention further develops the above-mentioned proposal, and by utilizing the hollow shape of the obtained graphite molding to contain an appropriate heat-resistant material inside, the function of this heat-resistant material is also exhibited. It is something to try.

【０００６】[0006]

【課題を解決するための手段】本発明は、熱可塑性樹脂
の粒子状物質と黒鉛粉末とを使用し、粒子状物質を黒鉛
粉末中に配置させた後、粒子状物質を溶融・炭化させる
ことにより中空状黒鉛成形物を製造するにあたり、前記
粒子状物質に予め耐熱性材料を含有させておくことを特
徴とする中空状黒鉛成形物の製造方法を要旨とする。According to the present invention, a particulate material of a thermoplastic resin and graphite powder are used, the particulate material is placed in the graphite powder, and then the particulate material is melted and carbonized. In producing the hollow graphite molded product according to, a gist of the method for producing a hollow graphite molded product is characterized in that the particulate material contains a heat-resistant material in advance.

【０００７】以下、詳述する。本発明で使用する熱可塑
性樹脂の粒子状物質は、熱処理による炭素収率が１〜１
０％程度のものが好ましく、例えば、ポリエチレン、ポ
リプロピレン、ポリスチレン、ナイロン、ポリ塩化ビニ
ル、ポリ酢酸ビニルなど種々のものが挙げられる。炭素
収率は熱処理の方法によって異なるため、熱可塑性樹脂
の種類によって熱処理の方法を適宜変えるとよい。例え
ば、ポリエチレン、ポリプロピレン、ポリスチレン、ナ
イロンなどは、酸化性雰囲気による不融化処理、次いで
非酸化性雰囲気による炭化処理を施すことにより炭素収
率が１〜１０％程度になるが、ポリ塩化ビニルやポリ酢
酸ビニルなどは同様の熱処理を施すと炭素収率がそれ以
上に大きくなるため、酸化性雰囲気による不融化処理を
施さずに非酸化性雰囲気による熱処理を施すのが好まし
い。粒子状物質の（耐熱性材料を含有しての）粒径は、
炭素収率の程度にもよるが、あまりに大きいと得られた
中空状黒鉛成形物の形状維持が困難になるため、大きく
ても数ｍｍ程度にするのがよい。また、使用する黒鉛粉
末の粒径とあまり差がないと成形が難しいため、黒鉛粉
末の粒径に対して５倍以上あることが好ましい。尚、前
記物質のうちポリエチレンは、得られる中空状黒鉛成形
物の形状が使用する粒子状物質としての形状によく対応
したものとなるため、特に好ましい。The details will be described below. The thermoplastic resin particulate matter used in the present invention has a carbon yield of 1 to 1 upon heat treatment.
It is preferably about 0%, and examples thereof include various materials such as polyethylene, polypropylene, polystyrene, nylon, polyvinyl chloride, and polyvinyl acetate. Since the carbon yield varies depending on the heat treatment method, the heat treatment method may be appropriately changed depending on the kind of the thermoplastic resin. For example, polyethylene, polypropylene, polystyrene, nylon, etc. have a carbon yield of about 1 to 10% when subjected to infusibilizing treatment in an oxidizing atmosphere and then carbonizing treatment in a non-oxidizing atmosphere. Since the carbon yield of vinyl acetate and the like increases further when subjected to the same heat treatment, it is preferable to perform heat treatment in a non-oxidizing atmosphere without performing infusibilizing treatment in an oxidizing atmosphere. The particle size (including the heat resistant material) of the particulate matter is
Although it depends on the degree of carbon yield, if it is too large, it becomes difficult to maintain the shape of the obtained hollow graphite molded product. Further, if the particle size of the graphite powder to be used is not so different, molding is difficult. Therefore, the particle size is preferably 5 times or more the particle size of the graphite powder. Among the above substances, polyethylene is particularly preferable because the shape of the obtained hollow graphite molded product corresponds well to the shape of the particulate substance used.

【０００８】熱可塑性樹脂の粒子状物質に含有させる耐
熱性材料としては、中空状黒鉛成形物を得るまでの熱処
理に耐えて中空状黒鉛成形物中に存在できるだけの耐熱
性を有するものであれば適宜使用できるが、一例を挙げ
れば、触媒機能や殺菌機能を発揮させる目的で金、銀、
銅、酸化チタンなどを使用したり、耐摩耗性や強度を向
上させる目的で粉末状の炭素繊維や黒鉛繊維を使用した
り、吸着機能を発揮させる目的で活性炭やゼオライトな
どを使用したりできる。ここで、複数の機能を有するも
のの場合、どの機能を発揮させるかは適宜である。ま
た、黒鉛粉末も含有させるものの一つとなり得る。As the heat-resistant material to be contained in the particulate material of the thermoplastic resin, any heat-resistant material that can withstand the heat treatment until the hollow graphite molded article is obtained and can exist in the hollow graphite molded article is used. Although they can be used as appropriate, as an example, gold, silver, or
Copper, titanium oxide or the like can be used, powdered carbon fiber or graphite fiber can be used for the purpose of improving wear resistance and strength, and activated carbon or zeolite can be used for the purpose of exerting an adsorption function. Here, in the case of a device having a plurality of functions, which function is to be exerted is appropriate. It can also be one of those containing graphite powder.

【０００９】耐熱性材料を熱可塑性樹脂の粒子状物質に
含有させるには、例えば、適宜造粒機を用いて耐熱性材
料を核として周りに熱可塑性樹脂粉末を被覆したり、耐
熱性材料と熱可塑性樹脂粉末との分散混合物を得、これ
を粒子状物質にし、必要に応じて、更にその外表面に熱
可塑性樹脂粉末を被覆したり、メカノケミカル的に熱可
塑性樹脂の粒子状物質に耐熱性材料を埋め込んだりすれ
ばよい。耐熱性材料と熱可塑性樹脂の使用割合も適宜で
ある。To incorporate the heat-resistant material into the particulate material of the thermoplastic resin, for example, a granulator is used to coat the thermoplastic resin powder around the core with the heat-resistant material as a core, or A dispersion mixture with a thermoplastic resin powder is obtained, and this is made into a particulate material, and if necessary, the outer surface is further coated with a thermoplastic resin powder, or mechanochemically resistant to the thermoplastic resin particulate material. The material may be embedded. The use ratio of the heat resistant material and the thermoplastic resin is also appropriate.

【００１０】黒鉛粉末としては、鱗片状黒鉛、鱗状黒
鉛、土壌黒鉛等の天然黒鉛や、人造黒鉛のいずれも使用
でき、得ようとする中空状黒鉛成形物の用途や前記（耐
熱性材料を含有する）粒子状物質の粒径を考慮して、黒
鉛粉末の性状や粒径を適宜選択すればよい。尚、黒鉛粉
末の中に粒子状物質を配置させるにあたっては、粒子状
物質の回りに得ようとする中空状黒鉛成形物の肉厚以上
の厚さに黒鉛粉末が集合物として存在すればよい。As the graphite powder, any of natural graphite such as flake graphite, flake graphite and soil graphite and artificial graphite can be used, and the intended use of the hollow graphite molded product and the above-mentioned The property and particle size of the graphite powder may be appropriately selected in consideration of the particle size of the particulate matter. When arranging the particulate matter in the graphite powder, the graphite powder may exist as an aggregate in a thickness equal to or larger than the wall thickness of the hollow graphite molded product to be obtained around the particulate matter.

【００１１】熱処理は前記したように、粒子状物質の種
類により、空気、酸素等の酸化性雰囲気により、室温か
ら２５０〜３５０℃まで昇温して不融化処理を施した
後、粒子状物質が炭化する温度まで、窒素、アルゴン等
の不活性ガス中や真空中等の非酸化性雰囲気による焼成
処理を施す場合と、酸化性雰囲気による不融化処理を施
さずに、直接非酸化性雰囲気による焼成処理を施す場合
とに分けられる。この焼成処理は、前記熱可塑性樹脂の
粒子状物質を用いた場合には、概ね、数百℃程度で十分
であるが、炭化した粒子状物質を黒鉛化させるために２
０００〜３０００℃の処理を施してもよい。ここで、耐
熱性材料が溶融して中空状黒鉛の内壁に皮膜状となった
りしても構わない。尚、熱処理終了後、余剰の黒鉛粉末
はふるいなどで除去する。また、耐熱性材料の機能は、
必要に応じて中空状黒鉛成形物を粉砕などした状態で発
揮させてもよい。As described above, the heat treatment is carried out by increasing the temperature from room temperature to 250 to 350 ° C. in an infusibilizing treatment with an oxidizing atmosphere such as air or oxygen depending on the type of the particulate matter, and then removing the particulate matter. When firing is performed in a non-oxidizing atmosphere such as in an inert gas such as nitrogen or argon or in a vacuum up to the temperature of carbonization, and when firing is performed directly in a non-oxidizing atmosphere without infusibilizing treatment in an oxidizing atmosphere. It is divided into the case of applying. When the particulate material of the thermoplastic resin is used, this baking treatment is generally performed at about several hundreds of degrees Celsius, but in order to graphitize the carbonized particulate material,
You may give a processing of 000-3000 degreeC. Here, the heat resistant material may be melted to form a film on the inner wall of the hollow graphite. After the heat treatment, excess graphite powder is removed with a sieve or the like. In addition, the function of the heat resistant material is
If necessary, the hollow graphite molded product may be brought into the state of being crushed.

【００１２】前述したように、中空状黒鉛成形物が形成
されるメカニズムは必ずしも定かではないが、黒鉛粉末
中に配置した熱可塑性樹脂の粒子状物質が熱処理により
一旦溶融して流動性を有するものとなり、これが黒鉛粉
末（集合物）相互の隙間に浸透し、換言すると、黒鉛粉
末粒子が次々と貼着し、その後、粒子状物質が炭化物と
して残存してバインダ−の役目をし、中空状黒鉛成形物
が形成されるものと考えられる。As described above, the mechanism by which a hollow graphite molded product is formed is not always clear, but the particulate matter of the thermoplastic resin placed in the graphite powder is once melted by heat treatment and has fluidity. This penetrates into the interstices between the graphite powders (aggregates), in other words, the graphite powder particles are stuck one after another, and then the particulate matter remains as carbides to serve as a binder, thereby forming hollow graphite. It is considered that a molded product is formed.

【００１３】得た中空状黒鉛成形物は、そのまま使用で
きるが、耐熱性材料で占められる以外の余裕が中空部分
にあれば、更に、他物質を充填することで性能の向上あ
るいは他機能の付加を図ることができる。例えば、潤滑
性オイルを充填すれば、液体潤滑材の機能も発揮できる
し、また例えば、接着剤を充填すれば導電性接着剤とし
ての機能も発揮できる。このとき、耐熱性材料として使
用するものとの組合せも考慮されてよく、例えば、耐熱
性材料として粉末状黒鉛繊維などを使用し、後から結合
材となる樹脂を充填すれば、加圧成形後焼成することで
高強度黒鉛成形体を容易につくり得る黒鉛成形体用材料
にもなるし、また例えば、耐熱性材料として活性炭を使
用し、後から薬剤を充填すれば、黒鉛による不活性さと
生体に対する馴染みのよさ、それに、活性炭による薬剤
の徐放機能とを合わせ有するものとなり、医療用に利用
することもできる。尚、中空部分への他物質充填方法
は、充填する物質を含む溶液の中に中空状黒鉛成形物を
浸漬するなどの一般的方法を用いることができる。The obtained hollow graphite molded product can be used as it is, but if the hollow portion has a margin other than that occupied by the heat resistant material, the performance can be improved or another function can be added by further filling with another substance. Can be achieved. For example, when filled with a lubricating oil, the function of a liquid lubricant can be exerted, and when filled with an adhesive, the function as a conductive adhesive can be exerted. At this time, a combination with a material used as a heat-resistant material may be considered, for example, if powdered graphite fibers are used as the heat-resistant material, and a resin to be a binder later is filled, it is possible to perform after pressure molding. By firing, it can also be used as a material for a graphite molded body that can easily form a high-strength graphite molded body. For example, if activated carbon is used as a heat-resistant material and a drug is filled later, the inertness due to graphite and biological It also has the familiarity with and the sustained release function of the drug by activated carbon, and can be used for medical purposes. As a method of filling the hollow portion with another substance, a general method such as immersing the hollow graphite molded product in a solution containing the substance to be filled can be used.

【００１４】[0014]

【実施例】 〈実施例１〉クラレコ−ルＧＣ（クラレケミカル（株）
製の粒状活性炭；粒度範囲２４〜４８メッシュ）の周り
にポリエチレン粉末（三井石油化学（株）製の粉末状ポ
リエチレン；粒度範囲１０〜５０μｍ）を被覆（転動造
粒機使用）して全体として直径約１０００μｍの粒子状
物質を得、これを黒鉛粉末ＣＰ（日本黒鉛工業（株）製
の天然鱗状黒鉛粉末；平均粒径７．０μｍ、粒度範囲１
〜４５μｍ）中に配置し、空気中で室温から３００℃ま
で１℃／分程度の速度で昇温させて３００℃で１時間保
持する不融化処理を施し、その後、窒素雰囲気中で６０
０℃、１時間で処理する焼成処理を施し（余剰の黒鉛粉
末は除去）、活性炭を内包する中空状黒鉛成形物を得
た。[Examples] <Example 1> Kuraray Coal GC (Kuraray Chemical Co., Ltd.)
Granular activated carbon manufactured by Mitsui Chemical Co., Ltd .; particle size range 24-48 mesh) and polyethylene powder (powdered polyethylene manufactured by Mitsui Petrochemical Co., Ltd .; particle size range 10-50 μm) are coated (using a rolling granulator) as a whole. A particulate substance having a diameter of about 1000 μm was obtained, and this was used as graphite powder CP (natural graphite graphite powder manufactured by Nippon Graphite Industry Co., Ltd .; average particle size 7.0 μm, particle size range 1
˜45 μm), the temperature is raised from room temperature to 300 ° C. in the air at a rate of about 1 ° C./min, and the temperature is maintained at 300 ° C. for 1 hour to perform infusibilization treatment, and then 60 ° C. in a nitrogen atmosphere.
Baking treatment was performed at 0 ° C. for 1 hour (excess graphite powder was removed) to obtain a hollow graphite molding containing activated carbon.

【００１５】〈実施例２〉粉末状炭素繊維（呉羽化学工
業（株）製；平均繊維径５μｍ、平均繊維長３０μｍ）
１０重量部とＳＮＰ−６６４３（（株）メタルカラ−製
のナイロン粉末；平均粒径４３μｍ）３０重量部とをミ
キサ−で均一に分散混合し、転動造粒機で造粒し、更に
その表面にＳＮＰ−６６４３（前述）を被覆して全体と
して直径約５００μｍの粒子状物質を得、これを実施例
１で使用の粒子状物質に代えて使用した以外、すべて実
施例１と同様にし、粉末炭素繊維を内包する中空状黒鉛
成形物を得た。Example 2 Powdered carbon fiber (Kureha Chemical Industry Co., Ltd .; average fiber diameter 5 μm, average fiber length 30 μm)
10 parts by weight and 30 parts by weight of SNP-6643 (Nylon powder manufactured by Metal Color Co., Ltd .; average particle diameter: 43 μm) were uniformly dispersed and mixed by a mixer, granulated by a tumbling granulator, and further the surface thereof. Was coated with SNP-6643 (described above) to obtain a particulate substance having a diameter of about 500 μm as a whole, which was used in place of the particulate substance used in Example 1, and the same procedure as in Example 1 was carried out to obtain a powder. A hollow graphite molding containing carbon fibers was obtained.

【００１６】〈実施例３〉ＭＦＰ−３１００（三井金属
鉱業（株）製の銀粉末；平均粒径１μｍ）５重量部をフ
ロ−ビ−ズＣＬ−２５０７（住友精化（株）製の真球状
ポリエチレン；粒度範囲１００〜２５０μｍ）２０重量
部とともにハイブリダイゼ−ション・システム（奈良機
械製作所製）により６０００ｒｐｍ、５分の条件で処理
して銀粉末を埋め込んだポリエチレンの粒子状物質を得
（余剰の銀粉末は除去）、これを黒鉛粉末ＣＳＳＰ（日
本黒鉛工業（株）製の天然鱗状黒鉛粉末；平均粒径１．
０μｍ、粒度範囲０．１〜５μｍ）中に配置し、以下、
実施例１と同様の熱処理を施して銀粉末を内包する中空
状黒鉛成形物を得た。Example 3 5 parts by weight of MFP-3100 (silver powder manufactured by Mitsui Mining & Smelting Co., Ltd .; average particle size: 1 μm) was added to a flow bead CL-2507 (manufactured by Sumitomo Seika Chemicals Co., Ltd.). Spherical polyethylene; particle size range 100-250 μm) 20 parts by weight together with a hybridization system (manufactured by Nara Machinery Co., Ltd.) at 6000 rpm for 5 minutes to obtain a silver particulate-embedded polyethylene particulate material (extra amount). (Silver powder is removed), and graphite powder CSSP (natural scaly graphite powder manufactured by Nippon Graphite Industry Co., Ltd .; average particle size 1.
0 μm, particle size range 0.1 to 5 μm), and
The same heat treatment as in Example 1 was performed to obtain a hollow graphite molding containing silver powder.

【００１７】[0017]

【発明の効果】本発明によれば、取り扱い性が良好な中
空状黒鉛成形物、しかも、内部に機能性の耐熱性材料を
含有するものを、複雑な製造工程を必要とすることなく
容易に得ることができる。EFFECTS OF THE INVENTION According to the present invention, it is possible to easily produce a hollow graphite molded product having a good handleability and further containing a functional heat-resistant material therein without requiring a complicated manufacturing process. Obtainable.

Claims (1)

【特許請求の範囲】[Claims] 【請求項１】 熱可塑性樹脂の粒子状物質と黒鉛粉末と
を使用し、粒子状物質を黒鉛粉末中に配置させた後、粒
子状物質を溶融・炭化させることにより中空状黒鉛成形
物を製造するにあたり、前記粒子状物質に予め耐熱性材
料を含有させておくことを特徴とする中空状黒鉛成形物
の製造方法。1. A hollow graphite molded article is produced by using a particulate material of a thermoplastic resin and graphite powder, arranging the particulate material in the graphite powder, and then melting and carbonizing the particulate material. In doing so, a method for producing a hollow graphite molded article, characterized in that the particulate material is made to previously contain a heat resistant material.