JPS62236826A - Coated metal wire - Google Patents

Abstract

PURPOSE:To obtain a coated metal wire for motion transmission which is flexible, excellent in friction and abrasion characteristics, etc., and suitable as, e.g., an inner cable of an automobile cable duct, by coating a wire with a polyamide copolymer containing a polyamide component and a polyglycol component in the molecule. CONSTITUTION:A polyamide forming monomer (e.g., 12-aminododecanoic acid or laurolactam) is polymerized to produce a polyamide component of a low degree of polymerization. This polyamide component is chemically bonded with a polyglycol component (e.g., polytetramethylene glycol) to produce a polyamide copolymer containing 30-95pts.wt. polyamide component and 70-5pts.wt. polyglycol component in the molecule. A wire is coated with the obtained polyamide copolymer. The coated metal wire can be suitably used for transmitting motion such as unidirectional motion, rotation or reciprocating motion.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a coated metal wire, and more specifically, it is used for transmitting motion such as motion in a fixed direction, rotational motion, reciprocating motion, etc. Concerning coated metal wire.

(Prior Art and Problems) Metal wires are widely used for the purpose of transmitting various motions, such as inner cables of cable conduits and wires for transmitting rotation to cars. These metal wires are widely coated with thermoplastic resin for the purpose of improving friction and wear characteristics and protecting the metal wires. Thermoplastic resins generally include polyethylene, polypropylene,
Polyamide and the like are used, and polyamide is preferably used especially when friction and wear characteristics and heat resistance are required.

However, although polyamide has excellent friction and wear characteristics, strength, and heat resistance, it is essentially a hard resin, which impairs the flexibility of metal wires, which may result in a lack of smooth movement and force transmission. Furthermore, when used at low temperatures, the coating may crack due to brittleness of the polyamide.

In order to improve these drawbacks, methods such as 1) adding a plasticizer and 2) blending the polyamide and a rubber component have been taken in order to make the polyamide flexible. However, those to which a plasticizer is added have the disadvantage that they harden during use due to volatilization, extraction, etc. of the plasticizer, and at low temperatures they lose flexibility due to reverse plasticization due to freezing of the plasticizer.

Blends of rubber, etc. have the disadvantage of significantly lower friction and wear characteristics.

The purpose of the present invention is to be flexible, not crack at low temperatures,
Another object of the present invention is to provide a coated metal wire for motion transmission that has excellent friction and wear characteristics and heat resistance.

(Means for Solving the Problems) The present invention is a coated metal wire for motion transmission coated with a polyamide copolymer having a polyamide component and a polyglycol component in the molecule.

The polyamide component in the present invention is a low degree of polymerization monopolymer or copolymer polymerized from polyamide-forming monomers. Examples of polyamide-forming monomers include lactams such as caprolactam and lauryllactam, ω-aminocarboxylic acids such as 12-aminododecanoic acid and 11-aminoundecanoic acid, adipic acid hexamethylene diamine salt,
Examples include salts of dicarboxylic acids and diamines such as hexamethylene diamine dodecanoic acid salt and isophthalic acid isoborone diamine salt. Among these, when the polyamide component is a polyamide polymerized from lauryllactam, 12-aminododecanoic acid, and 11-aminoundecanoic acid, the most preferable coated metal wire can be obtained since the change in physical properties due to water absorption is small.

The amount of polyamide component used is preferably 30 to 95 parts by weight. If the amount of the polyamide component exceeds 95 parts by weight, the flexibility will not be sufficient, and therefore the coated metal wire will not have sufficient flexibility. If the polyamide component is less than 30 parts by weight, the friction and wear properties, heat resistance, and mechanical strength will be reduced, and therefore the characteristics of the metal wire coated with polyamide cannot be obtained.

Examples of the polyglycol component include polyethylene glycol, polypropylene glycol, and ramethylene glycol. Polytetramethylene glycol is most preferably used because of its stability against water and heat, and those having an average molecular weight of 300 to 2,200 are even more preferably used.

Any method may be used to chemically bond the polyamide component and the polyglycol component; for example, a method in which a dicarboxylic acid such as adipic acid or dodecanedioic acid is added during polymerization in substantially equimolar amounts with the polyglycol to bond the two through an ester bond; Alternatively, a method can be exemplified in which both ends of polyglycol are aminated and both ends of polyamide are connected as carboxyl groups with amide bonds. in particular,
For example, 12-aminododecanoic acid, α, ω-dihydroxy polytetramethylene glycol, and α, ω-dihydroxy polytetramethylene glycol and equimolar amounts of dodecanedioic acid are heated to 240°C for 2 hours in a nitrogen stream while stirring. Remove the generated condensation water, then 5 ml IO
Polymerization can be carried out by further proceeding the linearization for 5 hours under reduced pressure.

Dyes and pigments, various stabilizers, plasticizers, fillers, oils, etc. can be added to the coating material of the present invention. For example, polytetrafluoroethylene powder, graphite, molybdenum disulfide, silicone oil, etc. can be added.

The metal wire used in the present invention may be a single wire or two or more twisted wires.

(Effects of the Invention) The coated metal wire according to the present invention is flexible and has excellent abrasion characteristics, so it is preferably used, for example, in the inner cable of a cable conduit used in an automobile, or in the power transmission mechanism of an oAll device such as a printer. obtain.

(Example) The present invention will be explained in more detail with reference to Examples below.

Examples 1 to 3, Comparative Examples 1 to 2 Ten twisted 0.11φ steel wires were coated with the resin shown in Table 1 to a thickness of about 0.2 mm by extrusion molding.

When this wire was used as a wire to transmit the power of the motor to another car as shown in Figure 1, the current consumption of the motor was measured, and the results are shown in Table 1.

Table 1 shows the results of a similar test conducted after heat aging this wire at 80° C. for one month.

It can be seen that the wire of the present invention is flexible and can easily transmit power.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the test method of Examples 1 to 3 and Comparative Examples 1 to 2. Figure 2 shows Examples 4 to 6 and Comparative Examples 3 to 6.
FIG. 4 is an explanatory diagram showing test method No. 4. 1...Car connected to a motor, 2.3...Car, 4
...Wire, 5...Wire fixing part, 6...Outer tube, 7...Inner cable

Claims (1)

[Scope of Claims] 1. A coated metal wire for motion transmission coated with a polyamide copolymer having a polyamide component and a polyglycol component in the molecule. 2. The coated metal wire according to claim 1, wherein the polyamide component is a polyamide polymerized from 12-aminododecanoic acid, lauryllactam or 11-aminoundecanoic acid, and the polygol component is polytetramethylene glycol. 3. The coated metal wire according to claim 1 or 2, wherein the polyamide component is 30 to 95 parts by weight and the polyglycol component is 70 to 5 parts by weight.