JPH0721972B2 - Self-bonding insulated wire - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a self-bonding insulated wire using a novel coating material used for coil molding of telecommunications equipment, etc., and particularly excellent in bonding strength in a high temperature atmosphere. And a self-bonding insulated electric wire.

[Technical Background of the Invention and Problems Thereof] In coil moldings for telecommunications equipment, etc., after winding an insulated wire into a predetermined shape, varnish impregnation treatment and heat treatment are performed to fuse and solidify the wires. Things have been used.
However, in recent years, the varnish impregnation treatment process has various problems from the viewpoint of environment, safety and hygiene, or from the viewpoint of productivity and economical efficiency. The use of adhesive insulated wires has expanded.

Resins used for the fusion layer of the conventional self-fusing insulated wire include polyvinyl butyral, polyvinyl formal, polyester, and copolyamide, but these resins have a low softening temperature. A self-fusing insulated wire using a resin cannot retain sufficient fusion strength in a high temperature atmosphere, and has been limited to use in stationary equipment having a relatively low heat resistance category. on the other hand,
Recently, in telecommunications equipment, with the aim of downsizing, weight saving, and improvement of reliability, the demand for equipment with high heat resistance category has expanded, and self-sufficient self-bonding strength in a high-temperature atmosphere adapted to these equipments. There has been a strong demand for the development of fusible insulated wires.

[Object of the Invention] The object of the present invention is to meet the above-mentioned demands, and it exhibits sufficient fusion bonding strength not only at room temperature but also in a high temperature atmosphere, while providing flexibility and softening resistance. Is to provide an excellent self-bonding insulated wire.

[Summary of the Invention] As a result of intensive studies to achieve the above-mentioned object, the present inventors have found that a self-fusing insulated wire mainly composed of a phenoxy resin and a polyarylate resin is sufficient even in a high temperature atmosphere. The present invention has been completed by discovering that it exhibits excellent fusion strength and is excellent in flexibility and softening resistance. That is, the present invention relates to (A) phenoxy resin and (B)
A paint prepared by dissolving a polyarylate resin in an organic solvent,
It is a self-fusion-bonded insulated electric wire formed by coating and drying it on a conductor directly or via another insulating layer. The present invention also provides the coating composition with a (C) polyvalent isocyanate compound as a curing agent,
The self-fusing insulated electric wire uses one kind or two or more kinds selected from a phenol resin, a melamine resin, and an organic titanium compound.

As the phenoxy resin (A) used in the present invention, any resin can be used as long as it is a resin represented by the following structural formula.

Examples of commercially available products thereof include Bakelite phenoxy PKHH, PKHC, PKHJ (manufactured by United States Union Carbide Co., trade name), Eponol OL-53-B40 (manufactured by US Shell Co., trade name), EPX-25, EPX-26. (Made by Asahi Denka Co., Ltd., trade name), Y
P-50 (trade name, manufactured by Tohto Kasei Co., Ltd.) and the like can be mentioned, and these can be used alone or in admixture of two or more. The phenoxy resin in the present invention contributes to the formation of a fusion coating film having good flexibility, and the resin has a softening temperature of about 100 ° C., a fusion temperature during coil forming of 140 ° C. or higher, and is suitable at room temperature. Has fusion strength.

As the polyarylate resin (B) used in the present invention, any resin can be used as long as it is a resin represented by the following structural formula.

Examples of commercially available products of this resin include U-polymer U-10
0, U-2030, U-4015, U-8000 (manufactured by Unitika, trade name), DUREL-400 (manufactured by US Hooker, trade name) and the like, and these are used alone or in combination of two or more kinds. To be done. Polyarylate resin has a higher softening temperature (110 ° C to 180 ° C) than phenoxy resin, and the fusion temperature during coil forming is 150 to 230 ° C, but conversely the fusion strength in high temperature atmosphere. Is good. The present invention utilizes the features of polyarylate resin to enhance the fusion strength in a high temperature atmosphere.

The phenoxy resin (A) and the polyarylate resin (B) can be blended in any proportions, but the amount is 3 to 97% of each other.
It is preferable to blend in the range of% by weight. If the proportion of either one is less than 3% by weight, the fusion strength cannot be obtained, which is not preferable.

Therefore, the self-fusing insulated wire made of the phenoxy resin and the polyarylate resin of the present invention has good flexibility, the fusing temperature during coil forming is in the practical range, and the excellent fusing strength in a high temperature atmosphere. Have.
And by using the curing agent component described later together, it is possible to lower the fusion temperature during coil forming, and by further thermosetting the thermoplastic resin of the fusion coating film component described above into a crosslinked structure, The fusion strength in a high temperature atmosphere can be improved.

As the (C) curing agent used in the present invention, one or more kinds of polyvalent isocyanate, phenol resin, melamine resin and organic titanium compound can be used. Examples of the polyisocyanate include Desmodur AP stable, Desmodule CT stable (manufactured by Bayer, West Germany, trade name), Millionate MS-50 (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name) and the like. Examples of the phenol resin include resol type and novolac type phenol resins. Examples of the melamine resin include n-butylated melamine, isobutylated melamine, and octylated melamine. Examples of the organic titanium compound include titanium alkoxide, titanium acylate, titanium chelate and their derivatives. The mixing ratio of these is 1 to 50% by weight of polyisocyanate, 1 to 50% by weight of phenolic resin, 1 to 50% by weight of melamine resin, and 0.3 to 20% of organic titanium compound with respect to the total amount of phenoxy resin and polyarylate resin. % Is desirable. If the amount is less than these amounts, it does not contribute to the fusion strength in a high temperature atmosphere, which is not preferable. Further, when the content exceeds the above-mentioned amount, it becomes difficult to maintain the coating film in a semi-cure state when applied and dried on a conductor as a paint, the fusion strength becomes insufficient, and the flexibility of the coating film decreases. This is not preferable.

In the present invention, a coating material obtained by dissolving the above components in an organic solvent is applied and dried directly on the conductor or through another insulating layer. As another insulating layer, a layer formed by applying and drying a coating material having high heat resistance such as polyester resin, polyesterimide resin, polyhydantoin resin, polyamideimide resin, or polyimide resin is suitable. When the conductor is an aluminum wire, an alumite coating may be formed on the surface and used as an insulating layer. The coating and drying conditions (furnace model, furnace length, furnace temperature, die arrangement, number of coatings, linear speed, etc.) vary depending on the conductor diameter, fusing layer thickness, type of resin used, compounding amount, etc. Adjustments should be made so that the dressing remains semi-cured.

In the self-fusing insulated electric wire of the first invention obtained as described above, after the coil is formed, the fusion layer is softened by heating at about 100 to 250 ° C., and the coil is fused integrally. Further, in the case of the second invention using a curing agent, a cross-linking structure is further formed by heating, and a strong fusion-bonding layer that does not re-soften is formed.

EFFECT OF THE INVENTION The self-fusing insulated electric wire of the present invention has a large fusion strength at room temperature and a high fusion strength in a high temperature atmosphere, and is excellent in flexibility, softening resistance, etc. If it is applied to a coil or the like of a high telecommunications device, it is possible to manufacture a device having a small size, a light weight and a high reliability, which is industrially useful.

[Examples of the Invention] Next, the present invention will be described by examples.

Examples 1 to 7 Polyester imide paint TVE5360 on a copper wire with a conductor diameter of 0.5 mm
(Manufactured by our company, product name) was applied and introduced into a vertical baking furnace having a furnace length of 6 m and a furnace temperature of 410 ° C. to obtain a polyesterimide copper wire having an insulating layer coating thickness of 0.020 mm. On this polyester-imide copper wire, a paint prepared by dissolving each component shown in Table 1 in an organic solvent was applied, and introduced into a vertical baking furnace having a furnace length of 6 m and a furnace temperature of 330 ° C.,
A self-fusing insulated electric wire having a fusion coating thickness of 0.010 mm was manufactured.

Comparative Examples Examples 1 to 7 were paints prepared by dissolving the butyral resin shown in Table 1 in an organic solvent on a polyesterimide copper wire coated with the same polyesterimide paint as in Examples 1 to 7 and dried.
The coating and drying were carried out in the same manner as in (1) to produce a self-fusing insulated electric wire having a fusion coating thickness of 0.010 mm.

The self-bonding insulated electric wires produced in Examples 1 to 7 and Comparative Example were wound around a mandrel having a diameter of 4 mm according to ASTM-D-2519 to prepare a helical coil test piece having a length of about 75 mm. The test piece was heated under the fusion condition of 200 ° C. for 30 minutes, and the fusion strength was measured in the atmosphere of room temperature (25 ° C.), 130 ° C., and 155 ° C. The self-bonding insulated wire of the present invention exhibits not only the bonding strength at room temperature but also the excellent bonding strength in a high temperature atmosphere, and the remarkable effect of the present invention is exhibited. The results are shown in Table 1 together with the comparative examples.

 ─────────────────────────────────────────────────── --- Continuation of the front page (56) Reference JP-A-51-9881 (JP, A) JP-A-54-132790 (JP, A) JP-A-56-97911 (JP, A) JP-A-59- 159640 (JP, A) Actual development Sho 49-80374 (JP, U)

Claims (2)

[Claims] 1. A self-fusing method comprising applying a coating material prepared by dissolving (A) a phenoxy resin and (B) a polyarylate resin in an organic solvent, directly onto a conductor or through another insulating layer and drying. Insulated wire. 2. One or more selected from (A) a phenoxy resin, (B) a polyarylate resin, and (C) a curing agent selected from a polyvalent isocyanate compound, a phenol resin, a melamine resin and an organic titanium compound. A self-fusing insulated electric wire obtained by applying a coating material prepared by dissolving the above material and an organic solvent directly onto the conductor or through another insulating layer and drying.