JPS6311721B2 - - Google Patents
Info
- Publication number
- JPS6311721B2 JPS6311721B2 JP55003903A JP390380A JPS6311721B2 JP S6311721 B2 JPS6311721 B2 JP S6311721B2 JP 55003903 A JP55003903 A JP 55003903A JP 390380 A JP390380 A JP 390380A JP S6311721 B2 JPS6311721 B2 JP S6311721B2
- Authority
- JP
- Japan
- Prior art keywords
- fire
- electric wire
- insulating layer
- crosslinking
- polyethylene
- 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
Links
- 230000009970 fire resistant effect Effects 0.000 claims description 19
- 238000004132 cross linking Methods 0.000 claims description 18
- -1 polyethylene Polymers 0.000 claims description 15
- 239000004698 Polyethylene Substances 0.000 claims description 14
- 229920000573 polyethylene Polymers 0.000 claims description 14
- 239000000203 mixture Substances 0.000 claims description 7
- 239000004020 conductor Substances 0.000 claims description 6
- 239000011521 glass Substances 0.000 claims description 6
- 239000010445 mica Substances 0.000 claims description 6
- 229910052618 mica group Inorganic materials 0.000 claims description 6
- 238000010894 electron beam technology Methods 0.000 claims description 5
- 238000000034 method Methods 0.000 claims description 5
- 229920001296 polysiloxane Polymers 0.000 claims description 5
- 239000011256 inorganic filler Substances 0.000 claims description 4
- 229910003475 inorganic filler Inorganic materials 0.000 claims description 4
- 150000001451 organic peroxides Chemical class 0.000 claims description 4
- 229920005601 base polymer Polymers 0.000 claims description 2
- 229910052736 halogen Inorganic materials 0.000 claims 1
- 150000002367 halogens Chemical class 0.000 claims 1
- 229920000915 polyvinyl chloride Polymers 0.000 description 6
- 239000004800 polyvinyl chloride Substances 0.000 description 6
- 238000009413 insulation Methods 0.000 description 4
- NKSJNEHGWDZZQF-UHFFFAOYSA-N ethenyl(trimethoxy)silane Chemical compound CO[Si](OC)(OC)C=C NKSJNEHGWDZZQF-UHFFFAOYSA-N 0.000 description 3
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- WNROFYMDJYEPJX-UHFFFAOYSA-K aluminium hydroxide Chemical compound [OH-].[OH-].[OH-].[Al+3] WNROFYMDJYEPJX-UHFFFAOYSA-K 0.000 description 2
- 239000003054 catalyst Substances 0.000 description 2
- 238000002485 combustion reaction Methods 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 229910000041 hydrogen chloride Inorganic materials 0.000 description 2
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 description 2
- 239000012212 insulator Substances 0.000 description 2
- 238000005979 thermal decomposition reaction Methods 0.000 description 2
- HGTUJZTUQFXBIH-UHFFFAOYSA-N (2,3-dimethyl-3-phenylbutan-2-yl)benzene Chemical group C=1C=CC=CC=1C(C)(C)C(C)(C)C1=CC=CC=C1 HGTUJZTUQFXBIH-UHFFFAOYSA-N 0.000 description 1
- XMNIXWIUMCBBBL-UHFFFAOYSA-N 2-(2-phenylpropan-2-ylperoxy)propan-2-ylbenzene Chemical compound C=1C=CC=CC=1C(C)(C)OOC(C)(C)C1=CC=CC=C1 XMNIXWIUMCBBBL-UHFFFAOYSA-N 0.000 description 1
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 1
- 239000004594 Masterbatch (MB) Substances 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- UKLDJPRMSDWDSL-UHFFFAOYSA-L [dibutyl(dodecanoyloxy)stannyl] dodecanoate Chemical compound CCCCCCCCCCCC(=O)O[Sn](CCCC)(CCCC)OC(=O)CCCCCCCCCCC UKLDJPRMSDWDSL-UHFFFAOYSA-L 0.000 description 1
- 230000003712 anti-aging effect Effects 0.000 description 1
- 229910000019 calcium carbonate Inorganic materials 0.000 description 1
- 238000010382 chemical cross-linking Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000004927 clay Substances 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 229920001577 copolymer Polymers 0.000 description 1
- 229920003020 cross-linked polyethylene Polymers 0.000 description 1
- 239000004703 cross-linked polyethylene Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000000593 degrading effect Effects 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000005038 ethylene vinyl acetate Substances 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- ZLNQQNXFFQJAID-UHFFFAOYSA-L magnesium carbonate Chemical compound [Mg+2].[O-]C([O-])=O ZLNQQNXFFQJAID-UHFFFAOYSA-L 0.000 description 1
- 239000001095 magnesium carbonate Substances 0.000 description 1
- 229910000021 magnesium carbonate Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000012768 molten material Substances 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 229920001200 poly(ethylene-vinyl acetate) Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 229920002545 silicone oil Polymers 0.000 description 1
- 239000000454 talc Substances 0.000 description 1
- 229910052623 talc Inorganic materials 0.000 description 1
Landscapes
- Insulated Conductors (AREA)
- Processes Specially Adapted For Manufacturing Cables (AREA)
Description
【発明の詳細な説明】
本発明は耐火電線特に660V級以下の耐火電線
の改良に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in fire-resistant electric wires, particularly fire-resistant electric wires of 660V class or lower.
従来の耐火電線は、導体と、導体上に設けられ
たガラスマイカテープを主体とする耐火層と、そ
の上に設けられたポリエチレン絶縁体と、更にそ
の上に設けられたポリ塩化ビニル混和物からなる
シースから主に構成されている。 Conventional fire-resistant electric wires are made of a conductor, a fire-resistant layer mainly made of glass mica tape provided on the conductor, a polyethylene insulator provided on top of that, and a polyvinyl chloride mixture provided on top of that. It is mainly composed of a sheath.
この従来の耐火電線は、直接炎にさらされるよ
うな開放系の燃焼条件下では充分な特性を発揮す
るものの、電線管内の様な密閉系の条件下では第
１図に示すように、耐火性能の低下が著しいもの
であつた。本発明者らがその原因を追求したとこ
ろ、電線管内ではゆつくりと温度が上昇して蒸し
焼き状態となる為に、まず、シース材料であるポ
リ塩化ビニルが熱分解し、それと同時に絶縁層の
ポリエチレンが溶融状態となるので、ポリ塩化ビ
ニルの熱分解生成物である塩化水素ガスが溶融ポ
リエチレン中に溶解し、更にこの塩化水素を含む
溶融ポリエチレンがガラスマイカテープ層に浸透
して炭化し、その結果耐火層の絶縁抵抗が著しく
低下して性能をおとすことがわかつた。 Although this conventional fire-resistant wire exhibits sufficient characteristics under open combustion conditions such as being directly exposed to flame, its fire-resistance performance deteriorates under closed system conditions such as inside a conduit, as shown in Figure 1. The decrease was significant. When the inventors investigated the cause of this problem, they found that the temperature inside the conduit slowly rises and it becomes a steam-baked state, so first the polyvinyl chloride that is the sheath material decomposes, and at the same time, the polyvinyl chloride that is the insulating layer becomes molten, hydrogen chloride gas, which is a thermal decomposition product of polyvinyl chloride, dissolves in the molten polyethylene, and the molten polyethylene containing hydrogen chloride penetrates the glass mica tape layer and carbonizes, resulting in It was found that the insulation resistance of the fireproof layer decreased significantly, degrading its performance.
本発明者らは、この問題を解決するため鋭意研
究を進めた結果、絶縁層を架橋すれば、融点以上
に加熱されても熱分解を開始するまではその形状
が保たれる為、耐火層に溶融物が浸透することは
なく、絶縁抵抗が著しく低下するという現象が防
止できることをみいだした。 As a result of intensive research to solve this problem, the inventors of the present invention found that if the insulating layer is cross-linked, it will maintain its shape even when heated above its melting point until thermal decomposition begins. It has been found that the molten material does not penetrate into the wafer, and the phenomenon of a significant drop in insulation resistance can be prevented.
しかしながら、通常行なわれている、180℃以
上の高圧水蒸気を用いる化学架橋方式では、耐火
層の損傷が大きく、更に架橋時の残留水分が耐火
性能に悪影響を及ぼすので好ましくないことも見
いだした。 However, it has been found that the commonly used chemical crosslinking method using high-pressure steam at 180°C or higher is undesirable because it causes significant damage to the fireproof layer and furthermore, residual moisture during crosslinking has a negative effect on fireproof performance.
本発明はこのような知見に基づいてなされたも
ので、導体上に耐火層、絶縁層を設け、その外側
にシースを設けた耐火電線において、前記耐火層
をガラスマイカテープで形成し、かつ前記絶縁層
を、電子線架橋、有機過酸化物架橋、シリコーン
グラフト架橋から選ばれた架橋方法にて架橋させ
た耐火電線を提供するものである。 The present invention has been made based on such knowledge, and provides a fire-resistant electric wire in which a fire-resistant layer and an insulating layer are provided on a conductor, and a sheath is provided on the outside of the wire. The present invention provides a fire-resistant electric wire in which an insulating layer is crosslinked by a crosslinking method selected from electron beam crosslinking, organic peroxide crosslinking, and silicone graft crosslinking.
本発明においては、絶縁層は主にポリエチレン
で形成されるが、更に無機質充填剤の添加された
ポリエチレン組成物で形成されれば一層効果的で
ある。 In the present invention, the insulating layer is mainly formed of polyethylene, but it is even more effective if it is formed of a polyethylene composition to which an inorganic filler is added.
この場合、無機質充填剤として汎用のタルク、
クレー、炭酸カルシウム等を使用しても良いが、
特に、水酸化アルミニウムや炭酸マグネシウムを
使用すれば、その良好な難燃性、絶縁性の為特に
効果的である。無機質充填剤の量はポリエチレン
の物性を低下させない程度が好ましく、ベースポ
リマー100重量部に対して15〜40重量部が適切で、
それ以上添加する場合はポリエチレンにエチレン
―プロピレン共重合体やエチレン―酢酸ビニル共
重合体をブレンドして使用するのが好ましい。 In this case, general-purpose talc is used as an inorganic filler.
Clay, calcium carbonate, etc. may be used, but
In particular, the use of aluminum hydroxide or magnesium carbonate is particularly effective because of their good flame retardancy and insulation properties. The amount of the inorganic filler is preferably an amount that does not reduce the physical properties of polyethylene, and is suitably 15 to 40 parts by weight based on 100 parts by weight of the base polymer.
When adding more than that, it is preferable to use a blend of polyethylene with ethylene-propylene copolymer or ethylene-vinyl acetate copolymer.
本発明における絶縁体の架橋方法としては、通
常の、電子線架橋、窒素ガスやシリコーンオイル
を熱媒体とするジクミルパーオキサシドやパーヘ
キシ25B等の有機過酸化物架橋、あるいはシリコ
ーングラフト架橋である。 The method of crosslinking the insulator in the present invention is conventional electron beam crosslinking, organic peroxide crosslinking such as dicumyl peroxide or perhexy 25B using nitrogen gas or silicone oil as a heating medium, or silicone graft crosslinking. .
シリコーングラフト架橋とは、ポリエチレンに
ビニルトリメトキシシラン（VTMOS）とジク
ミルパーオキサシド（DCP）とを加えて200℃で
反応させ、得られたシリコーングラフト化ポリエ
チレンにジブチルチンジラウレート（DBTDL）
等のシリコーン縮合触媒を混和させると、微量の
水分により架橋するもので、放置しておくだけで
空気中の水分により架橋するので、電子線架橋や
有機過酸化物架橋のような架橋設備を特に必要と
しない。 Silicone graft crosslinking is the process of adding vinyltrimethoxysilane (VTMOS) and dicumyl peroxaside (DCP) to polyethylene and reacting them at 200°C.
When mixed with a silicone condensation catalyst such as, it crosslinks with a small amount of moisture, and if left alone, it will crosslink with moisture in the air, so crosslinking equipment such as electron beam crosslinking or organic peroxide crosslinking is especially recommended. do not need.
次に本発明の１例を第２図により説明すると、
導体１と外側にガラスマイカテープを巻付けて耐
火層２を形成し、その外側に架橋ポリエチレン絶
縁層３を設けて絶縁線心上に、ポリ塩化ビニル混
和物によるシース４を設けて本発明の耐火電線を
得た。 Next, an example of the present invention will be explained with reference to FIG.
A fireproof layer 2 is formed by wrapping a glass mica tape around the conductor 1, a cross-linked polyethylene insulating layer 3 is provided on the outside of the fireproof layer 2, and a sheath 4 made of a polyvinyl chloride mixture is provided on the insulated wire core. Obtained fireproof wire.
次に本発明の実施例について説明する。 Next, examples of the present invention will be described.
〔実施例 １〕
断面積２mm2の軟銅撚線上に、厚さ0.13mmのガラ
スマイカテープを、1/2ラツプ巻きで２枚重ね巻
きして厚さ約0.5mmの耐火層を形成させ、その上
に、シリコーングラフト化ポリエチレン（ポリエ
チレン100重量部、VTMOS ２重量部、DCP 0.1
重量部）と触媒マスターバツチ（ポリエチレン
100重量部、DBTDL 1.0重量部、老化防止剤1.0
重量部）とを、９：１で混合して約0.8mmの厚さ
に押出被覆し、得られた架橋絶縁線心３本を、ポ
リプロピレンのスプリツトひもを介在して撚合わ
せ、その上を押えテープで押え、つづいてシース
として汎用のポリ塩化ビニル混和物を1.5mmの厚
さに押出被覆し、600Vの耐火電線を得た。[Example 1] Two pieces of glass mica tape with a thickness of 0.13 mm were wrapped in a 1/2 wrap around an annealed copper stranded wire with a cross-sectional area of 2 mm 2 to form a fireproof layer with a thickness of about 0.5 mm. On top, silicone-grafted polyethylene (100 parts by weight of polyethylene, 2 parts by weight of VTMOS, 0.1 parts by weight of DCP)
parts by weight) and catalyst masterbatch (polyethylene
100 parts by weight, DBTDL 1.0 parts by weight, anti-aging agent 1.0
(parts by weight) were mixed in a ratio of 9:1 and extrusion coated to a thickness of about 0.8 mm, and the three obtained crosslinked insulated wire cores were twisted together with a polypropylene split string interposed, and the top was pressed. It was held down with tape and then extruded and coated with a general-purpose polyvinyl chloride mixture to a thickness of 1.5 mm as a sheath to obtain a 600V fire-resistant electric wire.
得られた耐火電線の、電線管内で行なつた耐火
試験結果は第３図に示す通りで、規格を充分満足
するものであつた。 The results of the fire resistance test of the obtained fire resistant electric wire conducted in the conduit tube are as shown in FIG. 3, and the results fully satisfied the standards.
〔実施例 ２〕
断面積３mm2の軟銅撚線上に、厚さ0.13mmのガラ
スマイカテープを1/2ラツプ巻きで２枚重ね巻き
して厚さ約0.5mmの耐火層を形成させ、その上に、
ポリエチレン100重量部に水酸化アルミニウム
（ハイジライトH42：昭和電工社製商品名）30重
量部を添加した組成物を、0.8mmの厚さに押出被
覆し、電子線架橋により架橋させて絶縁線心を
得、実施例１と同様に600V ３心の耐火電線を得
た。[Example 2] Two sheets of glass mica tape with a thickness of 0.13 mm were wrapped in a 1/2 wrap around an annealed copper stranded wire with a cross-sectional area of 3 mm 2 to form a fireproof layer with a thickness of about 0.5 mm. To,
A composition prepared by adding 30 parts by weight of aluminum hydroxide (Hygilite H42, a product name manufactured by Showa Denko K.K.) to 100 parts by weight of polyethylene was extruded to a thickness of 0.8 mm, and crosslinked by electron beam crosslinking to form an insulated wire core. A 600V three-core fireproof electric wire was obtained in the same manner as in Example 1.
得られた耐火電線の試験結果を第３図に合わせ
て示す。実施例１と同様充分規格を満足するもの
であつた。 The test results of the obtained fire-resistant electric wire are also shown in Figure 3. As in Example 1, it fully satisfied the specifications.
なお、耐火試験の規格は、昭和53年第７号の消
防庁告示に準ずるもので、AC600Vを印加した状
態で、JIS Ａ 1304の火災曲線に沿つて30分間加
熱し、これに耐え、その後絶縁抵抗が0.4MΩ以
上かつAC1500V １分の耐圧試験に合格する事と
なつている。 The fire resistance test standard is in accordance with the Fire and Disaster Management Agency Notification No. 7 of 1971, and is heated along the JIS A 1304 fire curve for 30 minutes with AC600V applied, withstood, and then insulated. The resistance is 0.4MΩ or more and it is required to pass a voltage test of 1500V AC for 1 minute.
以上の実施例から明らかなように、本発明の耐
火電線は電線管内の様な密閉条件下の燃焼に際し
ても充分絶縁性能を有し、極めて有用なものであ
る。 As is clear from the above examples, the fireproof electric wire of the present invention has sufficient insulation performance even during combustion under closed conditions such as in a conduit, and is extremely useful.
第１図は従来の耐火電線の耐火性能を示すグラ
フ、第２図は本発明耐火電線の１例を示す断面
図、第３図は本発明耐火電線の電線管内での耐火
性能を示すグラフである。
１……導体、２……耐火層、３……絶縁層、４
……シース。
Figure 1 is a graph showing the fire resistance performance of a conventional fire resistant electric wire, Figure 2 is a sectional view showing an example of the fire resistant electric wire of the present invention, and Figure 3 is a graph showing the fire resistance performance of the fire resistant electric wire of the present invention in a conduit. be. 1... Conductor, 2... Fireproof layer, 3... Insulating layer, 4
……sheath.
Claims (1)
シースを設けた耐火電線において、前記耐火層を
ガラスマイカテープで形成し、かつ前記絶縁層
を、電子線架橋、有機過酸化物架橋、シリコーン
グラフト架橋から選ばれた架橋方法にて架橋させ
たことを特徴とする耐火電線。 ２ 絶縁層はポリエチレンで形成される特許請求
の範囲第１項記載の耐火電線。 ３ 絶縁層はポリエチレンを主成分とする非ハロ
ゲン系ベースポリマーに無機質充填剤を添加した
組成物で形成される特許請求の範囲第１項記載の
耐火電線。[Scope of Claims] 1. A fire-resistant electric wire in which a fire-resistant layer and an insulating layer are provided on a conductor and a sheath is provided on the outside thereof, wherein the fire-resistant layer is formed of glass mica tape, and the insulating layer is formed by electron beam cross-linking, A fire-resistant electric wire characterized in that it is crosslinked using a crosslinking method selected from organic peroxide crosslinking and silicone graft crosslinking. 2. The fireproof electric wire according to claim 1, wherein the insulating layer is made of polyethylene. 3. The fire-resistant electric wire according to claim 1, wherein the insulating layer is formed of a composition obtained by adding an inorganic filler to a non-halogen base polymer mainly composed of polyethylene.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP390380A JPS56102007A (en) | 1980-01-17 | 1980-01-17 | Flame resisting wire |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP390380A JPS56102007A (en) | 1980-01-17 | 1980-01-17 | Flame resisting wire |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS56102007A JPS56102007A (en) | 1981-08-15 |
| JPS6311721B2 true JPS6311721B2 (en) | 1988-03-15 |
Family
ID=11570146
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP390380A Granted JPS56102007A (en) | 1980-01-17 | 1980-01-17 | Flame resisting wire |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS56102007A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH067450B2 (en) * | 1987-07-24 | 1994-01-26 | 日立電線株式会社 | Laminated laying flat cable |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5524349A (en) * | 1978-08-08 | 1980-02-21 | Dainichi Nippon Cables Ltd | Fire resisting wire |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5028268U (en) * | 1973-07-06 | 1975-04-01 | ||
| JPS50139273U (en) * | 1974-04-30 | 1975-11-17 |
-
1980
- 1980-01-17 JP JP390380A patent/JPS56102007A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5524349A (en) * | 1978-08-08 | 1980-02-21 | Dainichi Nippon Cables Ltd | Fire resisting wire |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS56102007A (en) | 1981-08-15 |
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