JPS588082B2 - Densen - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electric wire whose covering material is polyester containing polyhexamethylene terephthalate as a main component.

Electric wires covered with a covering material (hereinafter also simply referred to as covered electric wires) are used, for example, for general wiring in a linear shape, and so-called curl cords in which a spiral shape has shape retention properties.

Rubbers, which are commonly used as covering materials, require a curing process when manufacturing covered wires, and due to the complexity and cost of this process, other thermoplastic resins (e.g., polyvinyl chloride, polyethylene, polypropylene, nylon, etc.) are used. There is.

However, even with these alternative resins, high-speed coating is difficult to perform smoothly, the use of plasticizers that have undesirable effects in many areas is essential, or heat resistance and chemical resistance are required for the application. There are some drawbacks, such as not reaching the level expected.

As a result of intensive research into electric wires having wire sheathing materials that practically do not have such drawbacks, the present inventors have found that electric wires whose sheathing material is a specific polyester satisfy these requirements, and the present invention has been made. has been reached.

That is, the present invention provides an electric wire coated with a thermoplastic resin material, characterized in that the covering material is polyhexamethylene terephthalate having an intrinsic viscosity of 0.4 or more.

Polyhexamethylene terephthalate as used in the present invention is
Not only a homopolymer of polyhexamethylene terephthalate, but also a part of its terephthalic acid component and/or hexamethylene glycol component, for example, 30 molar or less, especially 20 molar or less, may be mixed with other difunctional carboxylic acids and/or Also included are copolyesters substituted with glycols.

Such other difunctional carboxylic acids include, for example, isophthalic acid, methyl terephthalic acid, naphthalic dicarboxylic acid, diphenyl dicarboxylic acid, diphenoxyethane dicarboxylic acid, cyphenyl ether dicarboxylic acid, cyphenyl sulfonic dicarboxylic acid, and hexahydrocarbonic acid. Terephthalic acid,
Examples include aromatic and aliphatic dicarboxylic acids such as adipic acid and sebacic acid, oxyacids such as oxybenzoic acid, hydroxyethoxybenzoic acid, and ε-oxycaproic acid.

Other glycols include, for example, ethylene glycol, fluoropylene glycol, trimethylene glycol,
Tetramethylene glycol pentamethylene glycol,
decamethylene glycol, neopentylene glycol,
Examples include cyclohexane dimethylol, tricyclodecane dimethylol, 2,2-his(β-hydroxyethoxyphenyl)propane, diethylene glycol, polyethylene glycol, polytetramethylene glycol, and the like.

In addition, the above-mentioned polyhexamethylene terephthalate includes polymers that can also obtain polyfunctional compounds of trifunctional or higher functionality such as pyromellitic acid, trimellitic acid, pentaerythritol, etc. and/or monofunctional compounds such as benzoic acid. Copolymerization may be carried out within a linear range.

Intrinsic viscosity of polyhexamethylene ethylene phthalate used in the present invention (measured at 35°C in orthochlorophenol)
is required to be 0.4 or more.

If it is less than 0.4, the polymer will be brittle and have insufficient flexibility, making it unsuitable as a coating material for electric wires.

Those having an intrinsic viscosity exceeding 2.5, especially those exceeding 30, are unsuitable because their melt viscosity is too high and processing is difficult.

In the electric wire of the present invention, there are no particular limitations on the type and size (diameter) of the metal portion that is a conductor;
It is particularly suitable for use in normal indoor wiring and telephone lines (curl cords).

Polyhexamethylene terephthalate used in the present invention includes one type of stabilizer (e.g. ultraviolet absorber, antioxidant, etc.), fluorescent brightener, nucleating agent, pigment, lubricant, flame retardant, flame retardant aid, etc. The above may be combined.

The copolyester ether having the above-mentioned specific composition used in the wire coating material of the present invention can be melt-molded,
Moreover, it has excellent curing properties and is a useful material as a wire coating material.

The wire coating has the advantage that conventionally known molding and the like can be used as is, and high-speed production is possible.

Hereinafter, the present invention will be explained in detail with reference to Examples.

In the examples, "parts" mean parts by weight.

In addition, the intrinsic viscosity [η] is O-chlorophenol 10rnl
Sample polymer 120 ~ was dissolved in and measured at 35°C.

Example 1 194 parts of dimethyl terephthalate, 236 parts of hexamethylene glycol, 0.17 parts of titanium tetrabutoxide
A portion of the mixture was placed in a reaction vessel equipped with a stirrer and gradually heated in a nitrogen atmosphere.

As a result of the reaction, methanol produced was distilled out of the system via a rectification column.

When the amount of methanol distilled out of the system reached about 94% of the theoretical amount, the temperature inside the system was raised to 240°C, and the pressure inside the system was gradually reduced to 30 mmHg after 30 minutes, and 0.5 mmHg after another 30 minutes.
[η)-1.01, softening point of the polymer obtained by polycondensation for about 3 hours at 5 mmHg or less, 148.0°C
Met.

After drying this polymer at 110° C. for 3 hours, it was coated with a wire having a thickness of 1.8 mm (combined of 4 wires) to a thickness of 04 mm using a 30 mm extruder.

The electric wire had a withstand voltage of 13,000 volts or more.

Comparative Example 1 A plasticized polyvinyl chloride coated wire having the same thickness as in Example 1 had a dielectric strength ratio of 2.000 volts.

Example 2 In Example 1, the acid component was dimethyl terephthalate 8
A polymer having [η) -0.94 was obtained by the same procedure except that a copolymer containing 5 moles of dimethyldecane-1,10-dicarboxylate and 15 moles of dimethyldecane-1,10-dicarboxylate was used.

This polymer was dried at 70°C for 12 hours, and the diameter was 0. 6
It was possible to coat an electric wire with a thickness of 0.08 mm at a coating speed of 150 m/min.

This withstand voltage was 11,000 volts.

Comparative Example 2 When the same operation as in Example 2 was carried out using plasticized polyvinyl chloride, polyethylene, and polypropylene as coating materials, a uniform coating with a thickness of 0.08 mm could not be obtained.

Claims (1)

[Claims] 1. An electric wire coated with a thermoplastic resin material, characterized in that the covering material is polyhexamethylene terephthalate having an intrinsic viscosity of 0.4 or more.