JPS6139410A - Ant preventive wire and cable - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application j] The present invention relates to electric wires and cables provided with termite-proof properties.

[Conventional technology] Electrical wires and cables for control, power, communication, etc. that are buried underground in termite habitats or installed underground conduits are damaged by termites, causing major problems in energy and information transmission. Accidents are happening.

As a measure against such accidents, in recent years, nylon has been added to the jQ outer sheath of electric wires and 7-couple wires41! Built-in termite-proof electric wire cables are in practical use.

[Problems that 9mei aims to solve] The termite-proofing properties of nylon are said to be more due to its physical hardness than its chemical composition, and in fact, rigid plastics such as epoxy, polycarbonate, and polyacetal have no termite-proofing properties. It has been proven to be excellent.

As described above, the termite-proof property of Nylon is reliable, and this nylon is used as the outermost sheath ε of the TiM cable by extrusion or tape wrapping.

Nylon is covered with a sheath made of polynib, polyvinyl chloride, polyvinyl chloride, etc. In electric wires and cables, nylon is a rigid polymer, so slight foreign objects, irregularities, and injury stress are likely to concentrate on the surface. If there is a defective part, there is a problem in that it becomes a starting point and easily cracks not only at room temperature but also at a high temperature of about 50°C due to the so-called notch effect.

The present invention is based on item 2 and aims to provide electric wires and cables having termite-proofing properties with significantly improved crack resistance.

Means for Solving Problems C] The electric wire/cable of the present invention has an extruded coating layer of a composition made of nylon 11 or nylon 12 added with a substance obtained by modifying a urethane prepolymer with alcohol, and a plastic or rubber sheath. It is characterized in that it is provided on the outer periphery of the.

In the present invention, nylon 11 is made from 1,1-aminoundecanoic acid using castor oil as a raw material, and nylon 12 is made from laurinlactam using butadiene as a raw material.

There are many types of nylon scales such as 6,66,610, but these two are limited to nylon 11 and 12.
This is because one type has extremely superior extrusion processability compared to other types, making it ideal for use in electric wires and cables that require processing within the thickness and up to large sizes.

Additionally, these two have significantly lower water absorption than other nylons. Water acts as a softening agent in nylon, and if the cable absorbs or passes through water, it will cause problems in terms of maintaining its electrical performance.
Ru.

Furthermore, Nylon 11.12 has stronger resistance to formic acid than nylon. Termites emit formic acid to destroy attacking objects, but being strong against this is an advantage above all else.

Furthermore, nylon 11 and 1 have excellent cold resistance.
2, both of them have good 5J resistance at temperatures below -50℃, have high impact resistance and elongation, and have several characteristics compared to other nylons as sheath materials for electric wires and cables. are doing.

In this way, Nylon 11 is superior among nylons.
．． Even in the case of No. 12, if there is a notch, cracks easily occur when folded in half even at 20° C., which is not sufficient considering the line f1 etc. in practical use.

To achieve this characteristic, a substance obtained by modifying a urethane prepolymer with alcohol is used. Specifically, adiprene [-1I Ziprene L-160 (all brand names of DuPont), etc., is used with a carbon number of 1 to 6. alcohol,! , : A substance with a molecular weight of about 1100 to 2000 that has been modified with methanol or the like.

There is no particular limit to the amount of In added to this substance, but in terms of termite resistance, the harder it is, the better it is! ij2! i! In terms of sex, etc., the softer the better, so a delicate balance is necessary. Regarding termite resistance, it is said that a Shore D height of at least 65 or higher is preferred, and it is necessary to improve the notch resistance and fracture characteristics as best as possible within this range. 1 to 40 parts of Eu is preferable.

Such a composition is extruded and coated on the outer periphery of a sheath of polyethylene, polyvinyl chloride, chloroprene rubber, ethylene propylene rubber, etc. to form an anti-termite layer.

This thickness varies depending on the structure and dimensions of the electric wire/cable, but is generally about 1 m+, and small size cables may be thicker than R9<, and large size cables may be thicker than this.

The composition of the present invention may be a mixture of nylon 11 or nylon 12 with a nylon composition in which a material obtained by already modifying a urethane prepolymer with alcohol is added to nylon 11 or nylon 12.

[Example] Example 1 An OF in which insulating paper is wrapped around a 1000-1 conductor, an aluminum sheath is applied to the circumference of the core impregnated with insulating oil, and the outer circumference of this is covered with a polychloride sheath with a thickness of 7NR. used cable.

10% of nylon 12 is applied to the outer periphery of the poly-enriched vinyl sheath.
A composition containing 15 parts of adiprene L-100 modified with methanol was extrusion coated to a thickness of 1.2 mm.

Example 2 A cable similar to that of Example 1 was used.

10% of nylon-11 is applied to the outer circumference of the polyvinyl chloride sheath.
0mfiiS, a composition containing 10 parts by weight of a substance obtained by deforming adiprene L-100 with methanol r was prepared to a thickness of 1.2N.
Extrusion coating was performed on R.

Comparative example 1 The same OF cable as in Example 1 was used.

Nylon 11 is placed around the outer circumference of the polyvinyl chloride sheath.
．． Extrusion coated to 2M.

Comparative example 2 The same OF cable as in Example 1 was used.

Apply nylon 6 to a thickness of 1.5 mm around the outer circumference of the polyvinyl chloride sheath.
Extrusion coating was carried out at 2 mta.

The evaluation results for each cable of the example and comparative example are shown in Table 1.

Table 1: t:1: Extrusion processability and surface appearance when extruded using a 15011/m extrusion tank were investigated. A case where there is no problem on either side is marked as ○, and a case where there is a problem on either side is marked as ×.

*2: A knife wound with a depth of 0.6 mm (1/2 of the thickness) was made 1/4 of the way around the nylon layer of the sample cable, and the nylon layer was bent at 20°C to a diameter 15 times the outer diameter of the cable. The presence or absence of cracks was examined.

:I:3: The same method as *2 was followed except that m degrees were set to 0°C.

:I=/I: Cut each cable sample to length 1.51 ID1
1000Ky/ra 17)mm at 20℃.

When a concrete block with a 90° angle at a height of 300 m was pulled at a speed of 10 m/min on this cable, the presence or absence of the outer layer of the 1st layer was examined.

*5: The same method as 1=4 was followed except that the temperature was 40°C.

[Effects of the Invention] As explained above, according to the present invention, the
And, it is possible to realize electric wires and cables that have significantly improved notch impact resistance and cold resistance without impairing the characteristics such as termite resistance, water absorption resistance, formic acid resistance, and workability as described in Item 12.

Claims (1)

[Claims] (1) A termite-proof electric wire/cable characterized by having an extruded coating layer of a composition made of nylon 11 or nylon 12 added with an alcohol-denatured urethane prepolymer on the outer periphery of a plastic or rubber sheath. .