JP2598143B2 - Conductive resin composition - Google Patents
Conductive resin compositionInfo
- Publication number
- JP2598143B2 JP2598143B2 JP1328136A JP32813689A JP2598143B2 JP 2598143 B2 JP2598143 B2 JP 2598143B2 JP 1328136 A JP1328136 A JP 1328136A JP 32813689 A JP32813689 A JP 32813689A JP 2598143 B2 JP2598143 B2 JP 2598143B2
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- Prior art keywords
- conductive
- resin composition
- parts
- weight
- conductive resin
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は導電性の成形品を製造し、あるいは塗料、接
着剤などとして用いるに適した導電性の複合材料組成物
に関する。Description: TECHNICAL FIELD The present invention relates to a conductive composite material composition suitable for producing a conductive molded article or for use as a paint, an adhesive or the like.
〔従来の技術〕 エレクトロニクス技術の発展に伴い、静電気や電磁波
のシールド材等として、軽量であって高強度、高導電性
で、かつ成形性に優れた導電性樹脂組成物が求められる
ようになってきており、更にまた合成樹脂成形品に対し
て導電性を付与するための導電性塗料、あるいは導電性
接合を形成するための導電性接着剤などが求められるよ
うになっている。そして、かかる導電性組成物として
は、金属や炭素などの導電性物質の粒子あるいは繊維と
ゴム・プラスチックなどの合成樹脂とを配合して複合化
したものが一般的である。[Prior art] With the development of electronic technology, a conductive resin composition that is lightweight, has high strength, has high conductivity, and has excellent moldability has been required as a shielding material for static electricity and electromagnetic waves. In addition, a conductive paint for imparting conductivity to a synthetic resin molded article, a conductive adhesive for forming a conductive joint, and the like have been required. As such a conductive composition, a compound obtained by compounding particles or fibers of a conductive substance such as metal or carbon with a synthetic resin such as rubber or plastic is generally used.
このような従来の複合樹脂組成物においては、導電性
物質として金属材料を用いたものは一般に重く、また酸
化によって導電性能が劣化し易い欠点があり、劣化しが
たい材料を選択すると極めて高価でもある。一方、導電
性物質としての炭素材料は一般に金属材料より導電性が
劣るので、例えばカーボンブラック等の粉末材料を用い
て低抵抗の複合樹脂組成物を得ようとすると多量添加を
必要とする。従って、樹脂組成物の粘度上昇が大きく、
加工性が大幅に低下する。また樹脂混練時あるいは樹脂
を所望の形に成形する際に、せん断によりカーボンブラ
ックのストラクチャーの破壊が生じて電気抵抗率が変化
し、所望の電気抵抗率を得にくいうえ、外部応力によっ
て電気抵抗率が変化するという問題がある。In such a conventional composite resin composition, those using a metal material as a conductive substance are generally heavy, and have a drawback that the conductive performance tends to deteriorate due to oxidation. is there. On the other hand, since a carbon material as a conductive substance generally has lower conductivity than a metal material, a large amount of addition is required to obtain a low-resistance composite resin composition using, for example, a powder material such as carbon black. Therefore, the viscosity increase of the resin composition is large,
Workability is greatly reduced. Also, when kneading the resin or molding the resin into a desired shape, the structure of the carbon black is broken by shearing, and the electrical resistivity changes, making it difficult to obtain the desired electrical resistivity. There is a problem that changes.
また、カーボンブラックの代わりに電気抵抗率が変化
しにくい炭素繊維を配合しようとする提案があり、例え
ば特開昭64−65144には気相成長系炭素質繊維の黒鉛化
物を合成樹脂中に分散した樹脂配合物が開示されている
が、これとても複合樹脂組成物としての体積抵抗は10-1
〜101Ωcm程度であり、電磁波シールド材として必要と
される10-2Ωcmのレベルの体積抵抗は実現できていなか
った。In addition, there has been a proposal to mix carbon fiber whose electric resistivity is hardly changed in place of carbon black. For example, Japanese Patent Application Laid-Open No. 64-64144 discloses a method of dispersing a graphitized carbonaceous fiber of vapor growth type in a synthetic resin. Is disclosed, but the volume resistance as a very complex resin composition is 10 -1
It is about 10 1 Ωcm, and the volume resistance of the level of 10 -2 Ωcm required as an electromagnetic wave shielding material has not been realized.
このような事情の下で、本発明は、高く安定した導電
性を保持していて電磁波シールド材などとして使用する
ことが可能な導電性の複合樹脂材料を提供しようとする
ものである。Under such circumstances, an object of the present invention is to provide a conductive composite resin material which has high and stable conductivity and can be used as an electromagnetic wave shielding material or the like.
上記のような本発明の目的は、合成樹脂100重量部に
対して黒鉛繊維、特に直径0.1〜１μｍかつ長さ10μｍ
以下の黒鉛化した気相成長炭素繊維10〜100重量部及び
導電性カーボンブラック10〜80重量部を分散配合してな
る導電性樹脂組成物によって達成することができる。The object of the present invention as described above is to provide a graphite fiber, especially a diameter of 0.1 to 1 μm and a length of 10 μm per 100 parts by weight of a synthetic resin.
This can be achieved by a conductive resin composition obtained by dispersing and blending 10 to 100 parts by weight of the following graphitized vapor-grown carbon fiber and 10 to 80 parts by weight of conductive carbon black.
本発明の導電性樹脂組成物に用いられる黒鉛繊維とし
ては、例えばアクリル繊維などの有機繊維を高温下で熱
分解するか、あるいは炭化水素を気相熱分解することに
よって得られる炭素繊維を、たとえば不活性ガス雰囲気
中で加熱処理して黒鉛化したものを用いることができる
が、中でも気相成長炭素繊維を黒鉛化したものが好まし
い。Examples of the graphite fibers used in the conductive resin composition of the present invention include, for example, pyrolyzing organic fibers such as acrylic fibers at a high temperature, or carbon fibers obtained by vapor-phase pyrolysis of hydrocarbons. Graphite obtained by heat treatment in an inert gas atmosphere can be used, and among them, graphitized carbon fibers grown in vapor phase are preferable.
かかる気相成長炭素繊維は、トルエン、ベンゼン、ナ
フタレン等の芳香族炭化水素やプロパン、エタン、エチ
レン等の脂肪族炭化水素などの炭化水素化合物、好まし
くはベンゼンまたはナフタレンを原料として用い、かか
る原料をガス化して水素などのキャリヤガスと共に例え
ば900℃以上の高温下で炭化水素分解触媒と接触、分解
させる方法によって得ることができるが、特にガス化し
た原料を水素などのキャリヤガスと共に900〜1500℃の
反応帯域中に分散浮遊させた超微粒金属からなる触媒、
たとえば粒径100〜300オングストロームの鉄、ニッケ
ル、鉄−ニッケル合金などと接触、分解させるなどの方
法によって得たものが好ましく用いられる。Such a vapor-grown carbon fiber uses, as a raw material, a hydrocarbon compound such as an aromatic hydrocarbon such as toluene, benzene or naphthalene or an aliphatic hydrocarbon such as propane, ethane or ethylene, preferably benzene or naphthalene. It can be obtained by a method of gasifying and contacting with a hydrocarbon cracking catalyst at a high temperature of, for example, 900 ° C. or higher together with a carrier gas such as hydrogen, and a method of decomposing the material. A catalyst made of ultrafine metal dispersed and suspended in the reaction zone of
For example, those obtained by a method such as contacting and decomposing with iron, nickel, an iron-nickel alloy having a particle size of 100 to 300 angstroms are preferably used.
こうして得た炭素繊維は必要に応じてボールミル、ロ
ータースピードミル、カッティングミルその他の適宜の
粉砕機を用いて粉砕する。かかる粉砕は必須ではない
が、合成樹脂と配合する際に分散性が改良され、複合樹
脂組成物としての性能が向上するから実施することが好
ましい。The carbon fiber thus obtained is pulverized using a ball mill, a rotor speed mill, a cutting mill or another appropriate pulverizer as necessary. Such pulverization is not essential, but it is preferable to carry out the pulverization because the dispersibility is improved when blended with the synthetic resin and the performance as the composite resin composition is improved.
更に、こうして得た炭素繊維を、1500〜3500℃、好ま
しくは2500〜3000℃の温度で、３〜120分間、好ましく
は30〜60分間、アルゴン等の不活性ガスの雰囲気下で熱
処理することにより、好ましい性状の黒鉛繊維が得られ
る。Further, the thus obtained carbon fiber is heat-treated at a temperature of 1500 to 3500 ° C., preferably 2500 to 3000 ° C. for 3 to 120 minutes, preferably 30 to 60 minutes under an atmosphere of an inert gas such as argon. Thus, graphite fibers having preferable properties can be obtained.
また、本発明の導電性樹脂組成物に配合される導電性
カーボンブラックは、従来から合成樹脂などに導電性を
付与する為に使用されていたものが利用でき、例えばラ
イオンアクゾ社製のケッチェンブラックEC（商品名）な
どを用いることができる。Further, as the conductive carbon black to be added to the conductive resin composition of the present invention, those conventionally used for imparting conductivity to a synthetic resin or the like can be used. For example, Ketjen manufactured by Lion Akzo Co., Ltd. Black EC (trade name) or the like can be used.
本発明の導電性樹脂組成物に用いられる合成樹脂とし
ては、例えばポリエチレン、ポリプロピレン、ポリ塩化
ビニル、エチレン・酢ビ共重合体、エチレン・アクリル
酸エステル共重合体等の熱可塑性樹脂、例えばシリコー
ン樹脂、フェノール樹脂、ユリア樹脂、エポキシ樹脂等
の熱硬化性樹脂、また例えばクロロプレン、クロロスル
ホン化ポリエチレン、塩素化ポリエチレン、エチレン−
α−オレフィンゴム、エチレン−プロピレンゴム、シリ
コーンゴム、アクリルゴム、フッ素ゴム等のゴムが使用
できる。Examples of the synthetic resin used in the conductive resin composition of the present invention include thermoplastic resins such as polyethylene, polypropylene, polyvinyl chloride, ethylene / vinyl acetate copolymer, and ethylene / acrylate copolymer, for example, silicone resin. , Phenolic resins, urea resins, thermosetting resins such as epoxy resins, for example, chloroprene, chlorosulfonated polyethylene, chlorinated polyethylene, ethylene-
Rubbers such as α-olefin rubber, ethylene-propylene rubber, silicone rubber, acrylic rubber, and fluorine rubber can be used.
このような合成樹脂に黒鉛繊維と導電性カーボンブラ
ックを配合し分散させる方法としては、一般に使用され
る２本ロールミル、ニーダー、インターミックス、バン
バリーミキサー等の混練機が使用できる。As a method for mixing and dispersing the graphite fiber and the conductive carbon black into such a synthetic resin, a kneading machine such as a commonly used two-roll mill, kneader, intermix, and Banbury mixer can be used.
本発明の導電性樹脂組成物の配合組成は合成樹脂100
重量部に対して黒鉛繊維10〜100重量部であるのがよ
く、また導電性カーボンブラック10〜80重量部であるの
がよい。このうち黒鉛繊維の配合量は、電気抵抗率及び
加工、成形性などのバランスを考慮して使用する黒鉛繊
維の性状に基づいて選択されることが望ましい。更に導
電性カーボンブラックの配合量も、電気抵抗率及び加工
性などのバランスによって選択されることが望ましく、
黒鉛繊維と導電性カーボンブラックとの配合量の比は、
5:1〜1:1の範囲内にあることが好ましい。The composition of the conductive resin composition of the present invention is synthetic resin 100.
The amount is preferably 10 to 100 parts by weight of graphite fiber and 10 to 80 parts by weight of conductive carbon black. Of these, the blending amount of the graphite fiber is desirably selected based on the properties of the graphite fiber to be used in consideration of the balance between the electrical resistivity, the processing, and the moldability. Furthermore, it is desirable that the amount of the conductive carbon black is also selected according to the balance between the electrical resistivity and the processability,
The ratio of the blending amount of graphite fiber and conductive carbon black is
Preferably, it is in the range of 5: 1 to 1: 1.
また本発明の導電性樹脂組成物には、更に可塑剤、溶
剤、充填剤、加工助剤、酸化防止剤、架橋剤等の添加剤
を添加することができる。Further, additives such as a plasticizer, a solvent, a filler, a processing aid, an antioxidant, and a cross-linking agent can be further added to the conductive resin composition of the present invention.
本発明の導電性樹脂組成物が成形用であるときは、押
出し成形、射出成形、トランスファー成形、プレス成形
など各種の成形方法から、ベース樹脂及び成形物の形状
によって適宜の方法を選択して成形物を得ることができ
る。また塗料などであるときは、目的に応じてディッピ
ング、印刷、吹き付けなど適宜の方法を利用することが
できる。When the conductive resin composition of the present invention is for molding, molding is performed by selecting an appropriate method from various molding methods such as extrusion molding, injection molding, transfer molding, and press molding depending on the shape of the base resin and the molded product. You can get things. When it is a paint or the like, an appropriate method such as dipping, printing, or spraying can be used depending on the purpose.
本発明の導電性樹脂組成物に配合する黒鉛繊維は以下
のようにして製造した。Graphite fibers to be mixed with the conductive resin composition of the present invention were produced as follows.
1000〜1100℃に温度調節した縦型管状電気炉中に、下
方から水素を流しつつ粒径100〜300オングストロームの
金属鉄触媒粒子を浮遊させておき、これにベンゼンと水
素の混合ガスを下方から導入して分解させ、長さ10〜30
00μｍ、径0.1〜0.5μｍの炭素繊維を得た。次に、この
炭素繊維を遊星型ボールミル（フリッチュ・ジャパン株
式会社、Ｐ−５型）を用いて回転数500rpmで20分間粉砕
した。In a vertical tubular electric furnace controlled at a temperature of 1000 to 1100 ° C, metal iron catalyst particles with a particle size of 100 to 300 angstroms are suspended while flowing hydrogen from below, and a mixed gas of benzene and hydrogen is added to this from below. Introduce and disassemble, length 10-30
Carbon fibers having a diameter of 0.1 μm and a diameter of 0.1 to 0.5 μm were obtained. Next, this carbon fiber was ground using a planetary ball mill (Fritsch Japan KK, P-5 type) at a rotation speed of 500 rpm for 20 minutes.
次いで、この粉砕炭素繊維を電気炉に入れ、アルゴン
雰囲気下で2960〜3000℃に30分間保持して黒鉛化し、径
0.1〜0.5μｍ、長さが１〜10μｍである黒鉛繊維を得
た。Next, the crushed carbon fiber was placed in an electric furnace, and kept at 2960 to 3000 ° C. for 30 minutes in an argon atmosphere to be graphitized.
Graphite fibers having a length of 0.1 to 0.5 μm and a length of 1 to 10 μm were obtained.
合成樹脂としてエチレン酢酸ビニル樹脂（三井デュポ
ンケミカル社、エバフレックス250、以下単にEVAとい
う）を用い、参考例で得た黒鉛繊維と、導電性カーボン
ブラック（ライオンアクゾ社、ケッチェンブラックEC、
以下単にECという）とを、第１表に示す配合（数字は重
量部で表示した）に従って、６インチの２本ロールで20
分間混練した。次いでプレス成形により150×150×2mm
のシートを作成し、これらからそれぞれ長さ70mm、幅10
mm、厚さ2mmの試料片を切出して、ホイートストンブリ
ッジにより電気抵抗値を測定し、体積抵抗率を算出し
た。Ethylene vinyl acetate resin (Mitsui DuPont Chemical Co., Evaflex 250, hereinafter simply referred to as EVA) was used as the synthetic resin, and the graphite fiber obtained in Reference Example and conductive carbon black (Lion Akzo, Ketjen Black EC,
Hereinafter, simply referred to as EC), according to the composition shown in Table 1 (numbers are shown in parts by weight), 20
Kneaded for minutes. Then 150 × 150 × 2mm by press molding
Sheets of 70 mm length and 10 width each
A sample piece having a thickness of 2 mm and a thickness of 2 mm was cut out, and its electric resistance was measured using a Wheatstone bridge to calculate the volume resistivity.
その結果をまとめて第１表に示す。 The results are summarized in Table 1.
この試験において、黒鉛繊維の配合量が100重量部を
越えると体積抵抗率が徐々に増加するのに対し、カーボ
ンブラックの配合量が80重量部を超えると急激に体積抵
抗率が増加するが、これは組成物中の導電材料の分散性
が低下すると共に加工性も低下する結果、組成物の凝集
力が低くなって成形体中の構造的欠陥が増加するためと
考えられる。そして対照例の組成物に比べて本発明の組
成物は格段に低い体積抵抗率を有することが判る。 In this test, the volume resistivity increases gradually when the amount of graphite fiber exceeds 100 parts by weight, whereas the volume resistivity rapidly increases when the amount of carbon black exceeds 80 parts by weight, It is considered that this is because the dispersibility of the conductive material in the composition is reduced and the processability is also reduced. As a result, the cohesive force of the composition is reduced and the structural defects in the molded body are increased. And it turns out that the composition of this invention has a significantly lower volume resistivity than the composition of a control example.
本発明の導電性樹脂組成物は、高価な金属繊維などを
用いる代わりに炭素質の導電材料を用いた軽い複合材料
であり、そのうえ高い導電率をもつので、電磁遮蔽など
に利用できる特長がある。The conductive resin composition of the present invention is a light composite material using a carbonaceous conductive material instead of using expensive metal fibers and the like, and has a high conductivity, so that it has a feature that it can be used for electromagnetic shielding and the like. .
───────────────────────────────────────────────────── フロントページの続き (72)発明者 山梨 秀則 静岡県御殿場市川島田252 矢崎部品株 式会社内 (56)参考文献 特開 昭61−12753（ＪＰ，Ａ) 特開 昭64−101372（ＪＰ，Ａ) 特開 昭63−286468（ＪＰ，Ａ) 特開 平１−101343（ＪＰ，Ａ) ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hidenori Yamanashi 252 Kawashimada, Gotemba-shi, Shizuoka Prefecture Inside Yazaki Parts Co., Ltd. (56) References JP-A-61-12753 (JP, A) JP-A-64-101372 (JP) JP-A-63-286468 (JP, A) JP-A-1-101343 (JP, A)
Claims (2)
ｍかつ長さ10μｍ以下の黒鉛化した気相成長炭素繊維10
〜100重量部及び導電性カーボンブラック10〜80重量部
を分散配合してなる導電性樹脂組成物。1. A diameter of 0.1 to 1 μm per 100 parts by weight of a synthetic resin.
Graphite-grown carbon fiber 10 m in length and 10 μm or less in length
A conductive resin composition obtained by dispersing and blending about 100 parts by weight and about 10 to 80 parts by weight of conductive carbon black.
た超微粒金属触媒と炭化水素化合物とを接触して得たも
のである特許請求の範囲第１項記載の導電性樹脂組成
物。2. The conductive resin composition according to claim 1, wherein the vapor grown carbon fiber is obtained by contacting an ultrafine metal catalyst suspended in a high temperature zone with a hydrocarbon compound. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1328136A JP2598143B2 (en) | 1989-12-20 | 1989-12-20 | Conductive resin composition |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1328136A JP2598143B2 (en) | 1989-12-20 | 1989-12-20 | Conductive resin composition |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03250503A JPH03250503A (en) | 1991-11-08 |
| JP2598143B2 true JP2598143B2 (en) | 1997-04-09 |
Family
ID=18206898
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1328136A Expired - Lifetime JP2598143B2 (en) | 1989-12-20 | 1989-12-20 | Conductive resin composition |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2598143B2 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2125203A1 (en) * | 1993-08-12 | 1995-02-13 | David Andrew Benko | Graphite fiber reinforced tires & method of incorporating graphite fibers into an elastomer |
| ATE441950T1 (en) * | 2001-04-03 | 2009-09-15 | Kureha Corp | IC SOCKET |
| JP4759852B2 (en) * | 2001-06-01 | 2011-08-31 | Ｎｏｋ株式会社 | Rubber composition for electromagnetic wave shielding |
| JP2003110280A (en) * | 2001-09-28 | 2003-04-11 | Toyo Tire & Rubber Co Ltd | Electromagnetic wave shield material |
| JP5146804B2 (en) * | 2007-06-12 | 2013-02-20 | 日信工業株式会社 | Method for producing carbon fiber composite material using carbon nanofiber |
| KR101238969B1 (en) | 2008-07-10 | 2013-03-04 | 닛신 고오교오 가부시키가이샤 | Process for producing carbon nanofiber, carbon nanofiber, process for producing carbon fiber composite material from carbon nanofiber, and carbon fiber composite material |
| JP5695378B2 (en) * | 2010-09-24 | 2015-04-01 | 積水化学工業株式会社 | Vinyl-based resin composition molded body and flame-resistant sheet |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6112753A (en) * | 1984-06-27 | 1986-01-21 | Tokai Carbon Co Ltd | Conductive resin composition |
-
1989
- 1989-12-20 JP JP1328136A patent/JP2598143B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH03250503A (en) | 1991-11-08 |
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