JPS592314B2 - Self-bonding insulation paint - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a self-adhesive insulating paint having excellent heat resistance properties, particularly adhesion at high temperatures.

Generally, self-adhesive insulating paints are used as paints for forming the outermost adhesive layer of self-adhesive insulated wires used in coil forming.

Coil forming using self-bonding insulated wires does not require the use of impregnated varnish after coil forming as in the conventional method, and the wires can be thermally fused together by simply heating the coil formed body as it is. Because it can be done, the heat bonding process is extremely simplified, and it has great advantages such as excellent labor saving. Conventionally, polyvinyl resin has been used as the adhesive resin layer provided on the outermost layer of self-bonding insulated wires.
It is made of butyral resin, polyvinyl formal resin, alcohol-soluble nylon, etc., but since these resins have a low heat softening temperature, the adhesive layer formed cannot maintain a sufficient adhesive temperature at high temperatures. However, the operating temperature range was around 100°C.

In order to maintain sufficient adhesive strength at high temperatures, it is sufficient to form an adhesive resin layer using a resin with a high heat softening temperature. The process of forming the coil into a coil and then heat-sealing it requires a high-temperature device, making operation extremely difficult in practice.

Therefore, conventional self-fusing insulated wires have been limited to stationary equipment used at relatively low temperatures, such as transformers or television yoke coils, and their range of use is largely limited. This is what was being done.

On the other hand, in recent years, there has been a demand for self-bonding insulated wires with heat resistance as insulated wires used in these devices in order to reduce size, weight, and improve reliability in electrical equipment. Research into self-adhesive insulating paints that exhibit sufficient adhesive strength is being actively conducted.

The present invention was discovered as a result of intensive research in response to such demands. 10 to 200 parts by weight of a polysulfone resin and an organic titanium compound are added to 100 parts by weight of a polyhydroxy polyether resin having a molecular weight of about 10,000 or more. This self-adhesive insulating coating is characterized in that a mixture of 0.3 to 6.0 parts by weight of titanium is dissolved in an organic solvent.

To explain the self-adhesive insulating paint of the present invention in more detail, first,
The polyhydroxy polyether resin having a molecular weight of about 10,000 or more as a component is represented by the following general formula.

(However, in the formula, n is a positive integer, R1 is -0-, -S-S
02-, -CH2-, -C- group, R2 is hydrogen or an alkyl group) Specific examples of commercially available resins include Eponol OL-53-B40 (trade name of Shell Co., Ltd., USA), Bakelite Phenoxy shiPKHH 8 5 0
0,. Rei PRDA 8080 (trade name of Union Carbide Company, USA), EPX-25, EPX-2
6 (product name of Asahi Denka Kogyo Co., Ltd.), etc.

In addition, the molecular weight of the polyhydroxy polyether resin is about 10
The reason why the molecular weight is limited to 000 or more is that if a molecular weight of less than about 10,000 is used, the applied film will have poor plasticity.

Next, the polysulfone resin as the second component in the present invention is represented by the following general formula.

(In the formula, m is a positive integer.) Specific examples of commercially available resins include P-1700, . Examples include P-3500 (trade name of Union Carbide Company, USA).

In addition, in the present invention, the polysulfone resin is limited to 10 to 200 parts by weight per 100 parts by weight of the polyhydroxypolyether resin.If the amount is less than 10 parts by weight, the applied film will not have sufficient adhesive strength at high temperatures. 2.
This is because if the amount exceeds 0.00 parts by weight, the coated film will lack adhesiveness at room temperature and will not exhibit sufficient strength.

By adding the polysulfone resin in this way, a self-fusing paint that maintains excellent heat resistance over a long period of time can be obtained.

Furthermore, the organic titanium compound as the third component in the present invention can easily form a semi-cured state with the polyhydroxypolyether resin. , diethylene glycol,
A titanium compound reacted with octylene glycol, acetoacetate, etc. is used.

As a titanium chelate compound of octylene glycol, there is Orgachit OG (70% butanol solution, titanium content 5.2 ± 0.5% by weight) (trade name of Matsumoto Seika Kogyo Co., Ltd.), which is a titanium chelate compound of acetoacetic ester. Orgacit EAA (7
5% isopropyl alcohol solution, titanium content 9.9
±0.25% by weight) (product name of Matsumoto Seika Kogyo Co., Ltd.).

In addition, in the present invention, the amount of the titanium compound compounded is 10% of the polyhydroxypolyether resin based on the weight of titanium in the compound.
The reason for limiting the amount to 0.3 to 6.0 parts by weight is that if it is less than 0.3 parts by weight, the effect of crosslinking the polyhydroxypolyether resin is poor, and if it exceeds 6 parts by weight, This is because, on the contrary, adhesive strength decreases without improving heat resistance.

Next, examples of the present invention will be shown.

Examples 1 to 6 and Comparative Examples 1 to 6 A polyester imide varnish (trade name: Isomid, manufactured by Nippon Schenectaday Co., Ltd.) was coated and baked on a copper wire having a diameter of 0.5 m and 71 L to obtain an insulated wire having a coating of 25 μm in thickness.

Next, in order to measure the adhesive strength of the self-bonding insulated wires of the present invention having the compositions shown in Table 1, the insulated wires were coated with an insulating paint (insulating paint) on a round bar with a diameter of 5 mm. Examples 1 to 5 and Comparative Examples Self-fusing insulating paints (Comparative Examples 1 to 6) were applied to the outside of the above-mentioned insulated wires at a line speed of 15 m/min using a baking oven with a length of 3 m and a temperature of 300°C. By baking, a self-bonding insulated wire with an adhesive resin layer having a film thickness of 12 μm was obtained.

In addition, in order to compare with the conventional product, a product using polyvinyl butyral resin (trade name: BH-4, manufactured by Sekisui Chemical Co., Ltd.) as an adhesive layer was similarly prepared. After winding the coil to form a spiral coil with a length of 70 mm, the wires were bonded together by heating at 200°C for 30 minutes, and the adhesive strength was measured at room temperature and 150°C based on ASTM D-2519. As shown in the table. In addition, in order to compare with the self-bonding insulated wire to which the self-bonding insulating paint according to the method of the present invention was applied, an insulated wire obtained by applying polyester imide varnish to a copper wire with a diameter of 0.5 mm and baking it in the same manner as above was used. A spiral coil with a length of 70 mm is formed in the same manner as above,
This coil was coated with epoxyphenol-impregnated varnish (US PD).
Regarding the impregnated varnish coil (Comparative Example 7), which was immersed in Pedigrec waste 923 (trade name manufactured by GeOrge), air-dried, and fixed by heating at 160°C for 3 hours, the adhesive strength at room temperature and 150°C was measured in the same manner as above. The results are also listed in Table 2.

Regarding the flexibility of the adhesive resin layer, 1 for a 0.5 mm round bar.
The presence or absence of cracks after 0 winding was measured and all were found to be good. As is clear from the table above, the self-bonding insulated wire to which the self-bonding insulating paint of the present invention is applied has superior heat resistance properties compared to conventional self-bonding insulated wires and general-purpose impregnated varnish-treated insulated wires. In addition, the heat bonding process during coil formation is extremely easy, making it extremely useful as an electric wire for electrical equipment.

Claims (1)

[Claims] 1. A mixture in which 10 to 200 parts by weight of a polysulfone resin and 0.3 to 6.0 parts by weight of an organic titanium compound are respectively blended with 100 parts by weight of a polyhydroxy polyether resin having a molecular weight of about 10,000 or more. A self-adhesive insulating paint characterized by being dissolved in an organic solvent.