JPS6111412B2 - - Google Patents

Info

Publication number
JPS6111412B2
JPS6111412B2 JP52150600A JP15060077A JPS6111412B2 JP S6111412 B2 JPS6111412 B2 JP S6111412B2 JP 52150600 A JP52150600 A JP 52150600A JP 15060077 A JP15060077 A JP 15060077A JP S6111412 B2 JPS6111412 B2 JP S6111412B2
Authority
JP
Japan
Prior art keywords
foaming
degree
foaming agent
foamed plastic
insulated wire
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.)
Expired
Application number
JP52150600A
Other languages
English (en)
Other versions
JPS5484288A (en
Inventor
Masao Yuto
Yoichi Suzuki
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sumitomo Electric Industries Ltd
Original Assignee
Sumitomo Electric Industries Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Sumitomo Electric Industries Ltd filed Critical Sumitomo Electric Industries Ltd
Priority to JP15060077A priority Critical patent/JPS5484288A/ja
Priority to AU42334/78A priority patent/AU531473B2/en
Priority to DE2853626A priority patent/DE2853626C2/de
Priority to FR7835374A priority patent/FR2412149A1/fr
Priority to CA318,075A priority patent/CA1124950A/en
Priority to GB7848778A priority patent/GB2013960B/en
Publication of JPS5484288A publication Critical patent/JPS5484288A/ja
Priority to US06600870 priority patent/US4547328B1/en
Priority to US06/846,487 priority patent/US4683166A/en
Publication of JPS6111412B2 publication Critical patent/JPS6111412B2/ja
Granted legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
    • H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
    • H01B3/30—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes
    • H01B3/44—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes vinyl resins; acrylic resins
    • H01B3/441—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes vinyl resins; acrylic resins from alkenes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
    • B29C44/20—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles for articles of indefinite length
    • B29C44/32—Incorporating or moulding on preformed parts, e.g. linings, inserts or reinforcements
    • B29C44/322—Incorporating or moulding on preformed parts, e.g. linings, inserts or reinforcements the preformed parts being elongated inserts, e.g. cables
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B13/00—Apparatus or processes specially adapted for manufacturing conductors or cables
    • H01B13/06—Insulating conductors or cables
    • H01B13/14—Insulating conductors or cables by extrusion
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B7/00—Insulated conductors or cables characterised by their form
    • H01B7/17—Protection against damage caused by external factors, e.g. sheaths or armouring
    • H01B7/28—Protection against damage caused by moisture, corrosion, chemical attack or weather
    • H01B7/282—Preventing penetration of fluid, e.g. water or humidity, into conductor or cable
    • H01B7/285—Preventing penetration of fluid, e.g. water or humidity, into conductor or cable by completely or partially filling interstices in the cable
    • H01B7/2855—Preventing penetration of fluid, e.g. water or humidity, into conductor or cable by completely or partially filling interstices in the cable using foamed plastic
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A30/00—Adapting or protecting infrastructure or their operation
    • Y02A30/14—Extreme weather resilient electric power supply systems, e.g. strengthening power lines or underground power cables
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/249921—Web or sheet containing structurally defined element or component
    • Y10T428/249953—Composite having voids in a component [e.g., porous, cellular, etc.]
    • Y10T428/249976—Voids specified as closed
    • Y10T428/249977—Specified thickness of void-containing component [absolute or relative], numerical cell dimension or density
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/249921—Web or sheet containing structurally defined element or component
    • Y10T428/249953—Composite having voids in a component [e.g., porous, cellular, etc.]
    • Y10T428/249987—With nonvoid component of specified composition
    • Y10T428/249988—Of about the same composition as, and adjacent to, the void-containing component
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/249921—Web or sheet containing structurally defined element or component
    • Y10T428/249953—Composite having voids in a component [e.g., porous, cellular, etc.]
    • Y10T428/249987—With nonvoid component of specified composition
    • Y10T428/249988—Of about the same composition as, and adjacent to, the void-containing component
    • Y10T428/249989—Integrally formed skin
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/249921—Web or sheet containing structurally defined element or component
    • Y10T428/249953—Composite having voids in a component [e.g., porous, cellular, etc.]
    • Y10T428/249987—With nonvoid component of specified composition
    • Y10T428/24999—Inorganic
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
    • Y10T428/2913—Rod, strand, filament or fiber
    • Y10T428/2973—Particular cross section
    • Y10T428/2975—Tubular or cellular

Landscapes

  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Extrusion Moulding Of Plastics Or The Like (AREA)
  • Molding Of Porous Articles (AREA)
  • Processes Specially Adapted For Manufacturing Cables (AREA)

Description

【発明の詳細な説明】
本発明は化学発泡剤、不活性気体発泡剤を用い
て発泡絶縁体を製造する際に、高発泡度で良好な
特性を有す発泡絶縁電線を容易に製造する方法に
関する。 発泡プラスチツクで絶縁されたケーブルは通信
ケーブルの分野ですでに広く使用されている。現
在通信ケーブルに使用されている発泡プラスチツ
ク絶縁体の発泡度は比重法で測定した値が大体10
％〜90％と非常に広範囲にわたつている。また発
泡プラスチツクス絶縁体の製造はスクリユーによ
る押出法が一般的であり、その際使用される発泡
剤としてはアゾジカルボンアミド、４，４−オキ
シビスベンゼンスルホニルヒドラジツドのような
化学発泡剤、窒素、アルゴン、炭酸ガス等の不活
性気体、メタン、プロパン、ブタン、ペンタン、
ヘキシン等の気体状又は液状の炭化水素及びモノ
フロロトリクロロメタン、ジフロロジクロロメタ
ン、トリフロロトリクロロエタン、テトラフロロ
ジクロロエタン等の気体状又は液状のフロロカー
ボン等がある。又、プラスチツクスとしては低密
度ポリエチレン、中密度ポリエチレン、高密度ポ
リエチレン、ポリプロピレン、ブチルゴムなどの
ポリオレフイン及びこれらの２種以上の混合物が
使用され、中でもポリエチレン、ポリプロピレン
が最も一般的である。 発泡度が20〜30％程度の発泡プラスチツク絶縁
体は上記の化学発泡剤あるいは不活性気体を用い
ることによつて比較的容易に製造することがで
き、またこの場合には使用されるプラスチツクス
は特に厳密な選択を必要としない。 しかし近年、ケーブルの電気特性の向上および
ケーブルの細径化が求められ、このため50％以上
の高発泡化が望まれてきた。そこで本発明者は
種々検討した結果、高発泡化にはプラスチツクス
の弾性が重要な要因であり、弾性の指標となるプ
ラスチツクスのスエリング比が高発泡プラスチツ
ク絶縁体を得るうえで大きな関係をもつているこ
とを見出し、発泡剤として炭化水素またはフロロ
カーボンを用い、スエリング比が40％以上75％以
下のプラスチツクスを使用して、発泡度67％以上
の高発泡プラスチツク絶縁電線を製造する方法を
先に提案した（特願昭51−140755）。 高発泡プラスチツク絶縁電線の製造に関し、本
発明者等が更に研究を進めた結果、発泡剤として
アゾジカルボンアミド、４，4′−オキシビスベン
ゼンスルホニルヒドラジドのような化学発泡剤、
窒素、アルゴン、炭酸ガス等の不活性気体を用い
た場合にもスエリング比が55％以上のプラスチツ
クスを使用することによつて良好な特性を有す高
発泡プラスチツク絶縁電線が得られることを見出
し、本発明に到達したものである。 本発明において、スエリング比、SRはJIS−Ｋ
−6760又はASTMD 1238−70に規定されたメル
トインデクサーでメルトインデツクスMIを測定
する際（測定温度190℃、荷重2160ｇ）に得られ
る押出物の外径をdsとし、メルトインデクサー
にセツトされているオリフイスの内径をdoとし
たとき次式で表わされる。 SR＝ｄｓ−ｄｏ／ｄｏ×100（％） (注)ds、doはいづれも常温での測定値を用い
る。 メルトインデツクスの測定条件は次の通りであ
る。
【表】 本発明で使用されるプラスチツクスは、低密度
ポリエチレン、高密度ポリエチレン、ポリプロピ
レンの単独、またはこれら２種以上のブレンド体
で、ブレンド体の場合はスエリング比が55％以上
の樹脂を20％以上含む必要がある。 実施例 １ 第１表に示す樹脂に発泡剤としてアゾジカルボ
ンアミド1.5％を添加し、絶縁電線（導体径0.65
mm、絶縁外径1.8mm）を製造し、絶縁体の発泡度
および特性を調べた。
【表】 なお、発泡度は比重法で測定したもので、次式
で定義される。 発泡度（％）＝ρｏ−ρ／ρ×100 ρｏ：発泡前の樹脂の密度 ρ：発泡体の密度 実施例 ２ 第２表に示す樹脂に化学発泡剤アゾジカルボン
アミド0.5％を添加し、N2ガスを350c.c.／分の割合
で押出機中に圧入して絶縁電線（導体径0.4mm、
絶縁外径1.55mm）を製造し絶縁体の発泡度および
特性を調べた。
【表】
【表】 ただし、使用樹脂のSRは次の通りである。
【表】 実施例 ３ 第３表に示す樹脂にケイソウ土を２％添加し、
N2ガスを500c.c.／分の割合で押出機中に圧入して
絶縁電線（導体径0.65mm、絶縁外径1.60mm）を製
造し、特性を調べた。
【表】 上記の実施例より明らかなように、発泡剤とし
て化学発泡剤、不活性気体発泡剤を用いた場合に
スエリング比が55％以上のプラスチツクを用いる
ことによつて、発泡度55％以上で、良好な特性を
有す高発泡体絶縁電線が容易に得られることが判
る。また発泡度55％以下の低発泡体絶縁電線の製
造に本発明を適用することは当然可能であり、そ
の場合には本発明のプラスチツクを用いない場合
に比べて発泡剤の量が少くてすみ、その結果、発
泡剤残渣による押出加工性や電気特性の低下がな
い、高品質の発泡プラスチツク絶縁電線を製造す
ることができる。

Claims (1)

    【特許請求の範囲】
  1. １ 発泡剤として化学発泡剤および／または不活
    性気体発泡剤を使用して発泡絶縁電線を製造する
    際に、スエリング比が55％以上のプラスチツクを
    使用することを特徴とする発泡プラスチツク絶縁
    電線の製造方法。
JP15060077A 1977-12-16 1977-12-16 Manufacturing process of insulated wire with foamed plastics Granted JPS5484288A (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
JP15060077A JPS5484288A (en) 1977-12-16 1977-12-16 Manufacturing process of insulated wire with foamed plastics
AU42334/78A AU531473B2 (en) 1977-12-16 1978-12-08 Foamed plastic insulated wire
DE2853626A DE2853626C2 (de) 1977-12-16 1978-12-12 Mit einem geschäumten Kunststoff isolierter Draht und Verfahren zu seiner Herstellung
FR7835374A FR2412149A1 (fr) 1977-12-16 1978-12-15 Fil metallique isole par du plastique expanse et sa fabrication
CA318,075A CA1124950A (en) 1977-12-16 1978-12-15 Foamed plastic insulated wire and method for producing the same
GB7848778A GB2013960B (en) 1977-12-16 1978-12-15 Foamed plastics insulated wire and method for producing the same
US06600870 US4547328B1 (en) 1977-12-16 1984-04-16 Method for producing foamed plastic insulator
US06/846,487 US4683166A (en) 1977-12-16 1986-04-01 Foamed plastic insulated wire and method for producing same

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP15060077A JPS5484288A (en) 1977-12-16 1977-12-16 Manufacturing process of insulated wire with foamed plastics

Publications (2)

Publication Number Publication Date
JPS5484288A JPS5484288A (en) 1979-07-05
JPS6111412B2 true JPS6111412B2 (ja) 1986-04-02

Family

ID=15500414

Family Applications (1)

Application Number Title Priority Date Filing Date
JP15060077A Granted JPS5484288A (en) 1977-12-16 1977-12-16 Manufacturing process of insulated wire with foamed plastics

Country Status (2)

Country Link
US (1) US4683166A (ja)
JP (1) JPS5484288A (ja)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005255988A (ja) * 2004-02-10 2005-09-22 Sumitomo Chemical Co Ltd 押出発泡成形用エチレン−α−オレフィン共重合体および押出発泡成形品

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JPH0727527Y2 (ja) * 1988-04-13 1995-06-21 住友電気工業株式会社 シールド電線
US5098782A (en) * 1988-10-13 1992-03-24 Applied Extrusion Technologies, Inc. Extruded ethylenic polymer foam containing both open and closed cells
US5277515A (en) * 1988-10-13 1994-01-11 Applied Extrusion Technologies, Inc. Extruded ethylenic polymer foam containing both open and closed cells
US5215698A (en) * 1991-11-25 1993-06-01 Americraft Machined Products, Inc. Extrusion tool and method of extrusion coating
FI962715L (fi) * 1996-07-01 1998-01-02 Nk Cables Oy Koaksiaalinen suurtaajuuskaapeli sekä sen eriste
US6413623B2 (en) * 1997-06-02 2002-07-02 International Business Machines Corporation Method for attenuating thermal sensation when handling objects at non-body temperature
US6613983B1 (en) 1998-01-20 2003-09-02 Sumitomo Electric Industries, Ltd. Thin-conductor foamed-polyolefin-insulated wire and manufacturing method thereof
US6058883A (en) * 1998-06-26 2000-05-09 Robins; Anna Washable/reusable animal bedding element
JP3461758B2 (ja) 1999-07-19 2003-10-27 三菱電線工業株式会社 発泡用組成物および発泡同軸絶縁ケーブル
US6756538B1 (en) * 2003-01-29 2004-06-29 Conductores Monterrey S.A. De C.V. Coaxial cable having improved mechanical and electrical properties
US6858805B2 (en) * 2003-05-08 2005-02-22 Commscope Properties Llc Cable with foamed plastic insulation comprising and ultra-high die swell ratio polymeric material
FR2874736B1 (fr) * 2004-08-27 2006-11-03 Nexans Sa Dispositif de fabrication d'une gaine alveolee autour d'un conducteur
US8733405B2 (en) 2005-03-14 2014-05-27 Advanced Drainage Systems, Inc. Corrugated pipe with outer layer
CA2506986A1 (en) * 2005-05-10 2006-11-10 Garant Gp A shaft for tools, and tool and a method of fabrication thereof
JP2006339099A (ja) * 2005-06-06 2006-12-14 Hitachi Cable Ltd 発泡電線
WO2007106390A2 (en) 2006-03-10 2007-09-20 Amesbury Group, Inc Apparatus and method for manufacturing reinforced weatherstrip, and such a weatherstrip
CA2622695C (en) * 2007-02-26 2015-11-03 Advanced Drainage Systems, Inc. Pipe extrusion die flow path apparatus and method
CA2622692C (en) * 2007-02-26 2015-10-06 Advanced Drainage Systems, Inc. Defined ratio dual-wall pipe die
WO2008153691A1 (en) * 2007-05-23 2008-12-18 Advanced Drainage Systems, Inc. An extruder ramp-up control system and method
US8820801B2 (en) * 2007-11-16 2014-09-02 Advanced Drainage System, Inc. Multi-wall corrugated pipe couplings and methods
US8820800B2 (en) * 2007-11-16 2014-09-02 Advanced Drainage Systems, Inc. Multi-wall corrugated pipe couplings and methods
US7988438B2 (en) * 2008-02-11 2011-08-02 Advanced Drainage Systems, Inc. Extrusion die vacuum seals
US8114324B2 (en) 2008-10-14 2012-02-14 Advanced Drainage Systems, Inc. Apparatus and method for pressing an outer wall of pipe
US8550807B2 (en) * 2008-05-28 2013-10-08 Advanced Drainage Systems, Inc. In-mold punch apparatus and methods
US10329834B2 (en) 2015-02-13 2019-06-25 Amesbury Group, Inc. Low compression-force TPE weatherseals
CN116964690A (zh) * 2021-03-19 2023-10-27 住友电气工业株式会社 多芯线缆

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US4352701A (en) * 1973-08-21 1982-10-05 Sumitomo Electric Industries, Ltd. Process for the production of highly expanded polyolefin insulated wires and cables
US4049147A (en) * 1974-01-14 1977-09-20 National Distillers And Chemical Corporation Plastic skin envelopes for glass bottles and the like
US3986253A (en) * 1975-09-05 1976-10-19 Niemand Bros. Inc. Electrical insulator for armature shafts and method of installation
GB1595106A (en) * 1977-10-31 1981-08-05 Hoechst Holland Nv Foam plastic film of polyolefin material
US4547328B1 (en) * 1977-12-16 1998-04-14 Sumitomo Electric Industries Method for producing foamed plastic insulator

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005255988A (ja) * 2004-02-10 2005-09-22 Sumitomo Chemical Co Ltd 押出発泡成形用エチレン−α−オレフィン共重合体および押出発泡成形品

Also Published As

Publication number Publication date
US4683166A (en) 1987-07-28
JPS5484288A (en) 1979-07-05

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