JPS5849972B2 - Nijiyuuhifukuzetsuendenn - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an insulated wire applied to electric motors, transformers, and various electrical equipment, and more particularly to a double-covered wire with good heat resistance.

Insulated wires used in electrical equipment have been increasingly required to have higher performance in recent years as equipment has become smaller and larger in capacity.

Recently, polyamide resins and polyimide resins have been developed as insulating materials with excellent heat resistance, but these resins have the disadvantage of being expensive.

Nowadays, in order to satisfy various required characteristics, a technique of insulating conductors by baking two layers of different resins instead of using a single material has been widely adopted.

The aim of composite coatings is to take advantage of the strengths of each resin, but the strengths of one coating are often compromised to some extent by the other coating.

As mentioned above, the oldest example of a product is formal-nylon wire, which utilizes the slipperiness of nylon to further improve the windability of formal wire. It has the disadvantage of being slightly more expensive.

In addition, polyester resins whose upper layer is overcoated with amitoide resin are often used for the purpose of improving the heat resistance, but the heat resistance is still lowered to some extent compared to the amitoide resin alone.

As a result of intensive research aimed at improving the heat resistance of double-coated wires as described above, the inventors of the present invention have found that by overcoating a regular polyacrylic resin with an appropriate resin, they have achieved excellent heat resistance. We have found that a double-coated wire with high properties can be obtained.

That is, the gist of the present invention is that by adding, for example, an alkyl metal onto a nitrile-containing compound film and applying an L synthetic resin baking film, it has better heat resistance than any single resin, and also improves other electrical and mechanical properties. The present invention also provides an insulated wire with well-balanced performance.

One of the reasons why the heat resistance of the composite film as described above is superior to any single film is considered to be as follows.

That is, it is thought that this is because the nitrile group in the nitrile compound, which is the main component of the base resin, forms an idine ring structure as it deteriorates due to heat, and in particular, a compound that has an effect as a nucleophile is copolymerized in the base resin. When a carboxylic acid is introduced as a copolymer, it acts as an initiator for forming an idine ring structure, and formation of an imide bond may also occur, especially when a carboxylic acid is introduced as a copolymer.

It is believed that the formation of such imidine rings and i-do bonds is further promoted by the alkyl metal contained in the overcoat resin.

The polyacrylic resin used as the base resin is Compound I, which has one or more polymerizable unsaturated bonds and nitrile groups in its molecule, and a carboxyl group, carbonyl group, or amide group that acts as a nucleophile. It is a compound obtained by copolymerizing with one or more compounds having one or more groups, etc., and examples of preferred examples include -acrylonitrile/styrene/methacrylic acid copolymer, acrylonitrile/ethyl acrylate/
Glycidyl methacrylate/acrylic acid copolymer, acrylonitrile/methyl methacrylate/N-methylol acrylic acid copolymer, methacrylonitrile/ethyl acrylate/glycidyl methacrylate/methacrylic acid copolymer, acrylonitrile/styrene copolymer and ethyl acrylate/ These include methacrylic acid copolymerization and mixtures.

In addition, the overcoat resin used here is:
There is no particular restriction as long as the resin contains an alkyl metal or a metal amide, and suitable examples include polyurethane resins, polyvinyl formal resins, etc.
KBu, LiBu as alkyl metals and metal amides
vKNH2, NaNH2) LiNH2, Ca
(NH2) 2 and the like are preferably used, and the amount thereof is suitably 0.1 to 5% by weight, more preferably 0.2 to 3% by weight, based on the overcoat resin.

Furthermore, the ratio of the film thickness of the overcoat resin to the base resin is preferably 0.1 to 3.0, and preferably 0.1 to 0.8 in order to obtain better heat resistance.

In producing insulated wires in accordance with the present invention, both the base resin and the overcoat resin can be applied onto the conductor by conventional methods such as dip coating, spray coating or electrodeposition, and then baked in a known manner.

In this case, a good product can be obtained by overcoating after curing the base resin, but it is more effective to overcoat the base resin while it is uncured and then baking and curing the base resin and overcoat resin at the same time. It is.

Here, we will discuss position D, which is to economically produce higher-performance insulated wires, and the first case where a base resin is first electrodeposited onto the conductor, and then an overcoat resin is applied by dip coating.
This will be described in detail with reference to FIGS.

Figures 1 and 2 show a part of a drawing device for horizontal electrodeposited insulated wire. Indicates when is not used.

A conductive wire 1 running in FIG. 1 is electrodeposited with a water-dispersible varnish 3, which is a base resin, in an electrodeposition tank 2.

Subsequently, excess varnish is washed off with Java 4.

The conductor 1 with the electrodeposited layer is treated with a film-forming aid 6 in a post-treatment tank 5 .

Next, the electrodeposited film forming aid is removed by a roller wiper 7 and an air wiper 8.

Subsequently, the conductive wire 1 is dried in a drying oven 9, immersed in an overcoat resin 11 in an overcoat tank 10, and then baked in a final curing oven 12 to produce a double-coated insulated wire.

Suitable film forming aids used in this case include solvents that can dissolve or swell the electrodeposited base resin, such as ethyl cellosolve, butyl cellosolve, and N.

N-7 methylformamide, N,N-dimethylacedo, N-methyl-2-pyrrolidone and the like are preferably used.

Comparing FIG. 2 with FIG. 1, the process of applying a film-forming aid and the process of removing the electrodeposited film-forming aid are omitted, and a hot water treatment tank 13 is provided in their place. There is.

The purpose of installing the hot water treatment tank 13 is to treat the electrodeposited layer of water-dispersed varnish 30 electrodeposited in the electrodeposition tank 2 with hot water at a temperature higher than the lowest film forming temperature of the deposited resin, so that the water content is generally reduced to approximately A precipitated layer of about 60% may be rapidly reduced to a moisture content of about 20% to form a continuous film that is hard and tough enough not to be scratched even when touched by a guide roll or the like.

The temperature of hot water varies slightly depending on the type of precipitated resin, but
A preferred range is 50°C to 100°C.

Also, there is no problem with using a steam tank instead of hot water.

The electrodeposited conductive wire treated in the warm water treatment tank 13 as described above is immediately immersed in an overcoat resin 11 in an overcoat tank 10 and baked in a final hardening furnace 12.

At this time, after passing through the hot water treatment tank 13, it is dried in a drying oven 9, and then
Overcoating) There is no problem with overcoating in the tank 10.

As described above, the process based on FIG. 2 reduces costs and solves health and safety problems by not using a film-forming aid, and is considered to be a very effective process in the future.

The features of the present invention will be explained in detail by referring to reference examples.

Note that the scope of the present invention is not limited by the following examples.

Reference example 1 70 parts of acrylonitrile, 20 parts of ethyl acrylate,
5 parts of glycidyl methacrylate, 5 parts of methacrylic acid, 200 parts of ion exchange water, 1 part of lauryl sulfate ester soda.
After putting 5 parts into four Lof flasks and stirring for 30 minutes under nitrogen, 50 parts of ion-exchanged water containing 0.3 parts of potassium persulfate and 0.1 part of sodium bisulfite were added to bring the mixture to 55~
Aqueous dispersion A was obtained by reacting at 70°C for 5 minutes.

Put the above aqueous dispersion A into an electrodeposition tank with a length of 50 cm and a diameter of 0.5 mm.
A DC voltage of 2 V is applied between the opposite electrodes of the bare copper wire, and the wire speed is 2.
The wire was run at a speed of 0 m/min, and then immersed in N,N-dimethylformamide in a post-treatment tank for about 3 seconds, and then heated and cured to obtain an insulated wire with a finished coating of 25 μm.

Reference Example 2 Aqueous dispersion B was obtained in the same manner as in Reference Example 1, except that 50 parts of acrylonitrile, 30 parts of styrene, 72,110 parts of N-methylolacrylic, and 10 parts of acrylic acid were used as monomers.

Finished film 2 using the above aqueous dispersion B in the same manner as in Reference Example 1
A 6μ insulated wire was obtained.

Reference Example 3 Electrodeposition was performed in the same manner as in Reference Example 1 using the aqueous dispersion A used in Reference Example 1, and 8% was applied in a hot water treatment tank instead of the post-treatment tank.
After being immersed in warm water maintained at 8° C. for 2 seconds, the wire was cured by heating to obtain an insulated wire with a finished coating of 26 μm and a low gloss.

Reference Example 4 Using the aqueous dispersion B used in Reference Example 2, wire was drawn in the same manner as in Reference Example 3 to obtain an insulated wire with a finished film of 26 μm and low gloss.

Example 1 Electrodeposition was performed in the same manner as in Reference Example 1 using the aqueous dispersion A used in Reference Example 1, immersed in N-N-7 methylformamide in a post-treatment tank for 2 seconds, and then dried in a drying oven 9. LiBuo, 2%
The wire was overcoated with a polyvinyl formal paint (manufactured by Denki Kagaku Co., Ltd.) and cured by heating to obtain an insulated wire with a finished coating of 29 μm.

Example 2 Example 1 except that aqueous dispersion B used in Reference Example 2 was used.
An insulated wire with a finished film of 29μ was obtained in the same manner as above.

Example 3 Aqueous dispersion A was electrodeposited in the same manner as in Reference Example 1, immersed in N,N-dimethylformamide in a post-treatment tank for 2 seconds, and dried in a drying oven 9 to form a polyester containing 3% KBu O. A type paint (manufactured by Ryoden Kaoru Co., Ltd.) was overcoated and cured by heating to obtain an insulated wire with a finished coating of 30 μm.

Example 4 Aqueous dispersion B was electrodeposited in the same manner as in Reference Example 1, kept at 88°C in hot water treatment tank 13, and immersed in warm water for 2 seconds, followed by immediately dispersion of water-soluble polyester containing 3% KBuO. A resin (manufactured by Nitto Denko Corporation) was overcoated and cured by heating to obtain an insulated wire with a finished coating of 30 μm.

Example 5 Aqueous dispersion A was electrodeposited in the same manner as in Reference Example 1, immersed in hot water at 75°C [J for 2 seconds in a hot water treatment tank 13, and then immediately diluted with polyurethane containing 5% Li NH2O. A paint (manufactured by Bayer) was overcoated and cured by heating to obtain an insulated wire with a finished coating of 30 μm.

Example 6 Aqueous dispersion B was electrodeposited in the same manner as in Reference Example 1, and the hot water treatment tank 13
After immersing it in warm water held at 92°C for 2 seconds, it was immediately overcoated with a polyurethane paint (manufactured by Bayer AG) containing 7% NaBuO and cured by heating to give a finished film of 30 μm. Obtained insulated wire.

Table 1 shows the wire characteristics of the insulated wire obtained as above.
Shown below.

The remarkable effects of the present invention are clear from Table 7111).

[Brief explanation of the drawing]

FIGS. 1 and 2 are schematic diagrams showing a part of a drawing apparatus for a horizontal electrodeposited insulated wire, respectively. In the figure, 1 is a conductor, 2 is an electrodeposition bath, 3 is a water-dispersed varnish, 4 is Java, 5 is a post-treatment bath, 6 is a film forming aid, 7
8 is a roller wiper; 8 is an air wiper; 9 is a drying furnace; 10 is an overcoat tank; 11 is an overcoat resin; 12 is a final curing furnace; and 13 is a hot water treatment tank. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] 1. Copolymerizing a compound having one or more polymerizable unsaturated bonds and nitrile groups in the molecule and one or more compounds having one or more carboxyl groups, phenyl groups, or amide groups that act as nucleophiles. 1. A double-coated insulated wire comprising: an insulating layer made of a compound having a nitrile group obtained by the above method; and an insulating layer containing an alkyl metal or a metal amide on the insulating layer.