JPH08293215A - Fireproof cable - Google Patents

Abstract

PURPOSE: To provide a fireproof cable having heightened flame resistance and fireproof performance by forming a sheath using an inner layer sheath of polyolefin containing a predetermined amount of metal hydroxide and an outer layer sheath of required polyolefin containing a predetermined amount of metal hydroxide and the like. CONSTITUTION: The sheath of a fireproof cable is formed of an inner sheath 6 and an outer layer sheath 7. The sheath 6 contains 50 to 200 parts by weight of metal hydroxide against 100 parts by weight of polyolefin. Meanwhile, the sheath 7 contains 50 to 200 parts by weight of metal hydroxide and 1 to 100 parts by weight of high temperature crystallized frit against 100 parts by weight of polyolefin containing one kind or more of sheath 7 vinyl acetate copolymer. The ratio of the thickness of the layer 6 and the layer 7 is set to be 1/1 to 9/1. By using this sheath, the fireproof cable whose flame resistance and fireproof performance are heightened is obtained.

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、難燃性及び耐火特性に
優れた耐火ケーブルに関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fireproof cable having excellent flame retardancy and fireproof properties.

【０００２】[0002]

【従来の技術】ビルや地下街、地下駐車場等多数の人が
出入りする可能性のある場所では火災時における安全対
策として、スプリンクラ，水噴霧消火設備等の消火設備
や自動火災報知器，非常警報設備，誘導灯等の避難誘導
表示機器などには、一定時間電線としての機能を保持す
るための耐火電線が使用される。2. Description of the Related Art Fire extinguishing equipment such as sprinklers and water spray fire extinguishing equipment, automatic fire alarms, and emergency alarms are used as safety measures in the event of fire in places where many people may come and go, such as buildings, underground malls, and underground parking lots. Fireproof wires are used for equipment, evacuation guidance display devices such as guide lights, etc. to maintain the function as an electric wire for a certain period of time.

【０００３】これらに用いられる耐火電線は、従来ＪＩ
ＳＣ３００５の６０゜傾斜試験の難燃性レベルのものが
主流を占めてきた。しかし最近、ビルの高層化や地下
街、地下駐車場等の深層化に伴い、安全性向上の観点か
らハロゲンを含まないノンハロゲン難燃性で且つ垂直ト
レイ燃焼試験レベルの難燃性が要求されるようになっ
た。垂直トレイ燃焼試験レベルの高難燃化を実現するた
めには、シースの難燃性を向上させる必要がある。The refractory wires used for these are conventionally JI
The flame-retardant level of the SC3005 60 ° tilt test has become the mainstream. However, recently, with the rise of buildings and the deepening of underground shopping malls and underground parking lots, halogen-free non-halogen flame retardance and vertical tray combustion test level flame retardancy are required from the viewpoint of safety improvement. Became. It is necessary to improve the flame retardancy of the sheath in order to achieve high flame retardancy at the vertical tray combustion test level.

【０００４】シースをノンハロゲンで高難燃化するには
機械的特性等との絡みから難燃材として水酸化アルミニ
ウムや水酸化マグネシウムに代表される金属水酸化物の
混和量にも限界があり、これを補うためポリマの炭化を
促進させ、難燃性を向上させる目的でりん化合物等の難
燃化助剤が用いられる。In order to make the sheath non-halogen and highly flame-retardant, there is a limit to the amount of metal hydroxide represented by aluminum hydroxide or magnesium hydroxide as a flame-retardant material due to entanglement with mechanical properties. To supplement this, a flame retardant aid such as a phosphorus compound is used for the purpose of promoting carbonization of the polymer and improving flame retardancy.

【０００５】[0005]

【発明が解決しようとする課題】しかしながら、このよ
うなシースを使用したケーブルでは、逆にＪＩＳ−Ａ１
３０４に準じた耐火試験、特に電線管用試験において、
ポリエチレンや架橋ポリエチレン等のポリオレフィンか
らなる絶縁体が燃焼しづらくなり、蒸し焼き状態を経て
炭化し、その結果高温で著しい電気特性の低下を招き規
格を満足できなくなる。However, in a cable using such a sheath, conversely, JIS-A1 is used.
In the fire resistance test according to 304, especially in the conduit test,
Insulators made of polyolefin such as polyethylene and cross-linked polyethylene become difficult to burn, carbonize after being steamed, and as a result, electrical characteristics are remarkably deteriorated at high temperatures and the specifications cannot be satisfied.

【０００６】本発明者らは、難燃性と耐火特性を兼備さ
せるためのシースに焦点を当て鋭意検討の結果、内層は
耐火特性、外層は難燃性重視の組成とし、後者について
は酢酸ビニルコポリマに金属水酸化物及び高結晶化フリ
ットを混和することにより燃焼時の炭化強度が大幅に向
上することを見いだし、これらを組み合わせることによ
り目的とする性能を付与できることが分り本発明に至っ
たものであり、その目的は、高難燃性と耐火特性に優れ
た新規な耐火ケーブルを提供することにある。The inventors of the present invention have conducted intensive studies focusing on a sheath for having both flame retardancy and fire resistance. As a result, the inner layer has a composition with fire resistance and the outer layer has a flame retardance-oriented composition. It was found that by mixing a metal hydroxide and a highly crystallized frit with a copolymer, the carbonization strength at the time of combustion was significantly improved, and it was found that the intended performance can be imparted by combining these, which led to the present invention. It is an object of the present invention to provide a new fire resistant cable having high flame retardancy and excellent fire resistance.

【０００７】[0007]

【課題を解決するための手段】上記目的を達成するため
に請求項１の発明は、ポリオレフィン１００重量部に対
し、金属水酸化物５０〜２００重量部を含有する内層
と、少なくとも酢酸ビニルコポリマを１種以上含むポリ
オレフィン１００重量部に対し、金属水酸化物５０〜２
００重量部及び高温結晶化フリット１〜１００重量部を
含有する外層とからなるシースと備えた耐火ケーブルで
ある。In order to achieve the above object, the invention of claim 1 comprises an inner layer containing 50 to 200 parts by weight of a metal hydroxide with respect to 100 parts by weight of a polyolefin, and at least a vinyl acetate copolymer. 50 to 2 of metal hydroxide based on 100 parts by weight of polyolefin containing one or more kinds
A fire resistant cable comprising a sheath comprising an outer layer containing 00 parts by weight and 1-100 parts by weight of a high temperature crystallization frit.

【０００８】請求項２の発明は、内層／外層の厚さの比
率が１／１〜９／１である請求項１記載の耐火ケーブル
である。The invention of claim 2 is the fireproof cable according to claim 1, wherein the thickness ratio of the inner layer / outer layer is 1/1 to 9/1.

【０００９】[0009]

【作用】本発明でポリオレフィンとしてはポリエチレ
ン，エチレン酢酸ビニルコポリマ，エチレンエチルアク
リレートコポリマ，エチレンプロピレンゴム，エチレン
ブテンゴム等が挙げられ、これらは単独もしくは２種以
上併用してもよい。In the present invention, examples of the polyolefin include polyethylene, ethylene vinyl acetate copolymer, ethylene ethyl acrylate copolymer, ethylene propylene rubber, ethylene butene rubber, etc. These may be used alone or in combination of two or more kinds.

【００１０】金属水酸化物としては，水酸化アルミニウ
ム，水酸化マグネシウム，ニッケルと水酸化マグネシウ
ムとの固溶体，亜鉛と水酸化マグネシウムの固溶体，ハ
イドロタルサイト類，アルミン酸カルシウム等が挙げら
れるが、難燃性の点から水酸化マグネシウム等のマグネ
シウム水酸化物が好ましい。Examples of the metal hydroxide include aluminum hydroxide, magnesium hydroxide, a solid solution of nickel and magnesium hydroxide, a solid solution of zinc and magnesium hydroxide, hydrotalcites, calcium aluminate, etc. From the viewpoint of flammability, magnesium hydroxide such as magnesium hydroxide is preferable.

【００１１】内層はポリオレフィン１００重量部に対し
金属水酸化物を５０〜２００重量部とする必要があり、
５０重量部未満では難燃性が、また２００重量部を超え
ると機械的特性が著しく低下する。The inner layer must contain 50 to 200 parts by weight of metal hydroxide with respect to 100 parts by weight of polyolefin,
If the amount is less than 50 parts by weight, the flame retardancy is deteriorated, and if the amount exceeds 200 parts by weight, the mechanical properties are remarkably deteriorated.

【００１２】外層には酢酸ビニルコポリマを１種以上を
含むポリオレフィンを使用する必要があり、酢酸ビニル
コポリマを含まないと燃焼時の炭化強度が著しく低下し
難燃性が不十分となる。酢酸ビニルコポリマとしてはエ
チレン酢酸ビニルコポリマが最も代表的なポリマとして
挙げられる。For the outer layer, it is necessary to use a polyolefin containing at least one vinyl acetate copolymer, and if it does not contain the vinyl acetate copolymer, the carbonization strength at the time of combustion will be remarkably lowered and the flame retardance will be insufficient. As the vinyl acetate copolymer, ethylene vinyl acetate copolymer is the most representative polymer.

【００１３】混和する金属水酸化物は５０〜２００重量
部であり、５０重量部未満では目的とする難燃性を付与
できず、また２００重量部を超えると機械的特性の低下
が著しい。The amount of the metal hydroxide to be mixed is 50 to 200 parts by weight. If it is less than 50 parts by weight, the desired flame retardancy cannot be imparted, and if it exceeds 200 parts by weight, the mechanical properties are significantly deteriorated.

【００１４】更に本組成には高結晶化フリットを混和す
る必要があり、酢酸ビニルコポリマを含むポリオレフィ
ン１００重量部に対し、１〜１００重量部添加する。こ
こで高結晶化フリットとは、融点が３００℃〜７００℃
であり、これ以上の温度で結晶化するものをいう。Further, in this composition, it is necessary to mix a highly crystallized frit, and 1 to 100 parts by weight is added to 100 parts by weight of the polyolefin containing vinyl acetate copolymer. Here, the high crystallization frit has a melting point of 300 ° C to 700 ° C.
And that crystallize at a temperature higher than this.

【００１５】このような高結晶化フリットは、ポリオレ
フィン１００重量部に対し、１〜１００重量部混和させ
る。限界値未満であＨ炭化強度が不十分であり、一方限
定値を超えると機械的特性が大幅に低下するためであ
る。Such highly crystallized frit is mixed in an amount of 1 to 100 parts by weight with respect to 100 parts by weight of polyolefin. If it is less than the limit value, the H carbonization strength is insufficient, while if it exceeds the limit value, the mechanical properties are significantly reduced.

【００１６】本発明では、更に難燃助剤，酸化防止剤架
橋剤，架橋助剤，着色剤等を適宜加えてもよい。In the present invention, a flame retardant auxiliary agent, an antioxidant cross-linking agent, a cross-linking auxiliary agent, a colorant and the like may be added as appropriate.

【００１７】内層と外層の厚さの比率は１／１〜９／１
とすることが望ましい。The thickness ratio of the inner layer to the outer layer is 1/1 to 9/1.
Is desirable.

【００１８】[0018]

【実施例】以下、本発明の実施例を比較例と共に説明す
る。EXAMPLES Examples of the present invention will be described below together with comparative examples.

【００１９】先ず、耐火ケーブルの構造を図１により説
明する。First, the structure of the fireproof cable will be described with reference to FIG.

【００２０】図１において、１は導体、２は耐火層、３
は絶縁体、４は介在、５は押えテープ、６は内層シー
ス、７は外層シースであり、導体１の外周に耐火層２を
介して絶縁体３を被覆し、この絶縁体３を被覆した導体
１，１を介在４を介し、さらに押えテープ５を巻き付け
て内層シース６と外層シース７からなるシースに収容し
て２芯×１．２ｍｍφの耐火ケーブルを作製した。In FIG. 1, 1 is a conductor, 2 is a refractory layer, 3
Is an insulator, 4 is intervening, 5 is a holding tape, 6 is an inner layer sheath, and 7 is an outer layer sheath. The outer periphery of the conductor 1 is covered with the insulator 3 through the fireproof layer 2, and the insulator 3 is covered. A holding tape 5 was wound around the conductors 1 and 1 via the interposition 4 and housed in a sheath consisting of an inner layer sheath 6 and an outer layer sheath 7 to produce a 2-core × 1.2 mmφ fireproof cable.

【００２１】この耐火ケーブル中、内層シースと外層シ
ースは、表１に示すような配合で内層Ｉ−１〜Ｉ−４と
外層Ｏ−１〜Ｏ−７を準備し、これを表２に示す組み合
わせで使用し耐火ケーブルの評価を行った。In this fireproof cable, the inner layer sheath and the outer layer sheath were prepared as shown in Table 1 by preparing inner layers I-1 to I-4 and outer layers O-1 to O-7. The fireproof cables were evaluated by using them in combination.

【００２２】この評価した代表的なケーブルの実施例と
比較例を表１、表２に示す。Tables 1 and 2 show examples and comparative examples of the representative cables evaluated.

【００２３】[0023]

【表１】 [Table 1]

【００２４】[0024]

【表２】 [Table 2]

【００２５】作製した実施例１，２、比較例１〜９のケ
ーブルについて以下に示す評価を行った。The cables shown in Examples 1 and 2 and Comparative Examples 1 to 9 were evaluated as follows.

【００２６】(1) 引張試験 ケーブルからシースを切り取り、ＪＩＳ３号ダンベルで
試験片を打ち抜いた後、ＪＩＳＣ３００５に準拠し、引
張速度２００ｍｍ／分で測定した。(1) Tensile test The sheath was cut from the cable, the test piece was punched out with a JIS No. 3 dumbbell, and the tensile speed was measured at 200 mm / min according to JIS C3005.

【００２７】(2) 垂直トレイ燃焼試験 ＩＥＥＥ規格３８３に準拠した垂直トレイ燃焼試験法を
用い、長さ２．４ｍのケーブルを１０本垂直に並べ、下
端に７０．０００ＢＴＵ／ｈｒの炎を２０分間当てた。
その後、１．８ｍ未満で自己消災すれば合格（○）、
１．８ｍ以上延焼した場合には不合格（×）とした。(2) Vertical Tray Combustion Test Using the vertical tray combustion test method according to IEEE standard 383, 10 cables of 2.4 m in length are arranged vertically and a flame of 70.000 BTU / hr is placed at the lower end for 20 minutes. Hit
After that, if self-extinguishing within less than 1.8 m, pass (○),
When the fire was spread for 1.8 m or more, it was determined to be unacceptable (x).

【００２８】(3) 耐火特性 耐火・耐熱電線認定業務委員会で規定している管内試験
をＪＩＳ−Ａ１３０４に定める火炎温度曲線に従い、各
種試料ケーブルを３０分加熱し、３０分後絶縁抵抗測定
及び１５００Ｖ／１分の耐電圧試験を行い、絶縁抵抗が
０．４ＭΩ以上で絶縁破壊しないものを合格（○）、そ
れ以外のものは不合格（×）とした。(3) Fire resistance characteristics Various sample cables are heated for 30 minutes according to the flame temperature curve defined in JIS-A1304 in the in-pipe test stipulated by the Fire and Heat Resistant Wire Certification Operation Committee, and after 30 minutes the insulation resistance is measured and A withstand voltage test of 1500 V / 1 minute was performed, and those having an insulation resistance of 0.4 MΩ or more and not causing dielectric breakdown were passed (◯), and those other than that were rejected (×).

【００２９】表２から明らかなように、本発明の実施例
１，２に示す試料は、電気用品取締法でのポリエチレン
の引張特性規格値（引張強さ９．８ＭＰａ以上，伸び３
００％以上）を満足し、且つ垂直トレイ燃焼試験に合格
し、耐火特性に優れている。As is clear from Table 2, the samples shown in Examples 1 and 2 of the present invention are the polyethylene tensile property standard values (tensile strength 9.8 MPa or more, elongation 3) according to the Electrical Appliance and Material Control Law.
(100% or more), and passed the vertical tray combustion test, and has excellent fire resistance.

【００３０】これに対し、シースを１層とした比較例
１，２は難燃性あるいは耐火特性が不十分である。内層
の金属水酸化物の混和量が限定値外の比較例３，４では
引張特性，難燃性，耐火特性を全て満足することはでき
ない。また外層に酢酸ビニルコポリマを含まない比較例
５及び金属水酸化物の混和量が限定値外の比較例６，７
でも引張特性，難燃性、耐火特性を全て満足することは
できない。On the other hand, Comparative Examples 1 and 2 in which the sheath has one layer have insufficient flame retardancy or fire resistance. In Comparative Examples 3 and 4 in which the mixing amount of the metal hydroxide in the inner layer is out of the limit values, all the tensile properties, flame retardancy, and fire resistance properties cannot be satisfied. Further, Comparative Example 5 containing no vinyl acetate copolymer in the outer layer and Comparative Examples 6 and 7 in which the mixing amount of the metal hydroxide was out of the limit value.
However, it is not possible to satisfy all the tensile properties, flame retardancy, and fire resistance properties.

【００３１】結晶化フリットを含まない比較例８及び規
格外のフリットを用いた比較例９は難燃性が不十分であ
る。Comparative Example 8 containing no crystallization frit and Comparative Example 9 using a non-standardized frit had insufficient flame retardancy.

【００３２】[0032]

【発明の効果】以上要するに本発明によれば、特に優れ
た耐火性を発揮するため、火災時における信頼性が向上
し、安全対策に大きく貢献することができる等といった
優れた効果を発揮する。In summary, according to the present invention, particularly excellent fire resistance is exhibited, so that reliability in case of a fire is improved and it is possible to greatly contribute to safety measures.

【図面の簡単な説明】[Brief description of drawings]

【図１】本発明の耐火ケーブルの一例を示す断面図であ
る。FIG. 1 is a cross-sectional view showing an example of a fireproof cable of the present invention.

【符号の説明】[Explanation of symbols]

６ 内層シース ７ 外層シース 6 Inner layer sheath 7 Outer layer sheath

Claims (2)

【特許請求の範囲】[Claims] 【請求項１】 ポリオレフィン１００重量部に対し、金
属水酸化物５０〜２００重量部を含有する内層と、少な
くとも酢酸ビニルコポリマを１種以上含むポリオレフィ
ン１００重量部に対し、金属水酸化物５０〜２００重量
部及び高温結晶化フリット１〜１００重量部を含有する
外層とからなるシースと備えたことを特徴とする耐火ケ
ーブル。1. An inner layer containing 50 to 200 parts by weight of a metal hydroxide based on 100 parts by weight of a polyolefin, and 50 to 200 parts of a metal hydroxide based on 100 parts by weight of a polyolefin containing at least one vinyl acetate copolymer. A fireproof cable comprising a sheath comprising an outer layer containing 1 part by weight to 1 part to 100 parts by weight of a high temperature crystallization frit. 【請求項２】 内層／外層の厚さの比率が１／１〜９／
１である請求項１記載の耐火ケーブル。2. The inner layer / outer layer thickness ratio is 1/1 to 9 /
The fireproof cable according to claim 1, which is 1.