JPS58191769A - Production of electrodeposition coating for electric wire - Google Patents

Abstract

PURPOSE:A specific amount of polybutadiene is added to a monomer containing unsaturated bonds and graft polymerization is effected in the presence of an initiator and an emulsifier to produce an electrodeposition coating for electric wires such as enamelled copper wires. CONSTITUTION:For example, (A) 100pts.wt. of monomers having unsaturated bondages in their molecules consisting of e.g., (i) about 35-80wt% of acrylonitrile, (ii) 10-50wt% of a styrene, and (iii) a reactive monomer and acrylic ester monomer are combined with (B) 1-20pts.wt. of polybutadiene, (C) an initiator such as potassium persulfate and (D) an emulsifier such as sodium p-styrene- sulfonate. EFFECT:The additive of vinyl acetate or the like to component A helps stabilize its insulation and emulsion.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing an electrodeposition paint for electric wires.

Insulating turtle coated by electrodeposition using water-dispersed synthetic resin
Due to advances in manufacturing technology, ik@ has become comparable in all aspects, including economy, productivity, and performance, to insulation made using the normal dip coating method, and has come to be commercially available in large numbers as magnet wire. On the other hand, the performance of insulated wires has recently been improved by conventional dip coating, and efforts are being made to improve the characteristics of such insulated wires by improving the drawing process and electrodeposition face of the 'llk wire.
The present invention particularly seeks to provide a new electrodeposition paint for improving the performance of such electrodeposited enamel 11 wires.

Generally, as electrodeposition paints, water-soluble ones in which a polymeric substance is dissolved in water, and water-dispersed ones in which a polymeric substance is suspended in water as fine particles are used.

The latter aqueous dispersion type is mainly used for electric wires, such as emulsion polymerization method and chemical dispersion method.

physical dispersion method (4!! mechanical dispersion method), and the field I [Ik
The assembly method is manufactured by any method. The emulsification method 1 is a general method for currently commercially available ttii enameled electric wires, and is a method for obtaining a stable emulsion by radically polymerizing a vinyl monomer in an aqueous medium in the presence of a surfactant. This emulsion polymerization method has the advantage that raw materials are relatively inexpensive and the manufacturing method is easy. Next, the chemical dispersion method is a method of dispersing polyester, epoxy, epoxy-modified polyester, polyesterimide, polyamideimide, polyesteramideimide, polyimide, etc. using a special method, but at present the particle size is non-uniform and storage stability is poor. It has not been put into practical use due to problems. In addition, physical (mechanical) dispersion methods include formal,
It has the feature of being able to disperse a wide range of Th fats such as polyester, polyesterimide, polyamide, polyesterimide, epoxy, polyurethane, I-liimide, 4-lihyguntoin, I-lihydantoin epoxy, etc., but the particle size is quite large and stability is poor. There are other difficulties. Furthermore, the interfacial polymerization method is used for polyurethane.

Polyesteramide, polyamideimide, polyester, and polyesterimide have a wide range of applications, but there are many unresolved problems in manufacturing technology and cost considerations.

As described above, it is clear that the emulsion polymerization method described above is more advantageous than other methods for manufacturing one-piece enamel listening panels, but it is particularly important because the types of seven polymers that can be used for polymerization are limited. Due to performance constraints, it is inevitable that applications will be limited.

Here, to explain this emulsion polymerization in more detail, radical monomerizable vinyl monomers such as vinyl acetate, acrylonitrile, methacrylonitrile, styrene, p-methylstyrene, m-methylstyrene, 0-methylstyrene,
Methacrylic acid, methacrylic esters, acrylic acid,
Acrylic acid ester, vinyl pyridine, acrylamide, N-methylolacrylamide, glycidyl methacrylate, etc. are emulsified in an aqueous solution using a surfactant, and a water-soluble radical polymerization initiator such as potassium persulfate,
This is a method of homopolymerizing or copolymerizing the emulsified state 1 using ammonium persulfate to obtain an emulsion.

On the other hand, the insulation coating of enamelled wires has suffered from thermal problems in recent years.

Mechanical, i! Since a high level of awareness is required,
The bowl-shaped copolymer composition has been modified in various ways to satisfy each of these characteristics.

For example, a hexamer having a functional group such as an epoxy group, an amino group, an acid anhydride group, a carboxyl group, a hydroxyl group, or a methylol group is introduced into the copolymer composition, and the resulting copolymer is subjected to heat treatment. The aim is to improve the mechanical strength and heat resistance of the film by creating a three-dimensional structure through intermolecular or intramolecular crosslinking reactions, thereby improving the mechanical strength and heat resistance of the film. - using 1
It is possible to increase the glass transition temperature of the coalescence and give heat resistance to the polymer film, or conversely, to make monomers with low glass transition temperature such as ethyl acrylic, acrylic #kf lobil, and butyl acrylic in just 1 second. By adding it as part of the composition, it imparts appropriate flexibility to the polymer film.

However, there are generally only a few types of monomers that can be used in such copolymerization, and furthermore, taking into account factors such as price, the S types become even more limited.

Here, the present inventors investigated various methods of graft copolymerizing the above-mentioned various types of varnishes with the aim of improving the properties of the above-mentioned varnish. By letting
The present invention was achieved by discovering that the impact resistance, flexibility, etc. of the polymer film such as #1 can be significantly improved.

In other words, the present invention provides monocapsule 10 having an unsaturated bond in the molecule.
This is a method for producing a 11% coating material for T-line, characterized in that 1 to 20 parts by weight of polybutadiene is added to 0 parts by weight, and graft polymerization is carried out in the presence of an initiator and an emulsifier.

In this invention, the above-mentioned polybutadiene is a general rC rubber-like substance, and the presence of this substance brings about the above-mentioned flexibility, that is, during the above-mentioned polymerization, the crosslinking component and homopolymer have a high glass transition temperature, and these co-exist. This is thought to be due to the effect that occurs when the polymer structure is introduced into the polymer structure to impart a moderate amount of flexibility to the hard and brittle properties.

Embodiments of the present invention will be described below.

A total of 100 parts of co-monomer is added to 200 to 900 parts of ion-exchanged water, 0.05 to 1 part of a water-soluble initiator such as potassium persulfate or ammonium persulfate is added as an initiator, and a redox system is added. In this case, add 0.0% sodium bisulfite. 1 to 0.3 parts of O and 1 to 1.0 parts of a surfactant as an emulsifier are added, and the mixture is mixed at a polymerization temperature of 60 to 90° C. in a nitrogen atmosphere. Here, as the emulsifier, general anionic activators, cationic activators, and zwitterionic activators can be used, but preferably,
Good results have been obtained by using sodium salts such as sodium lauryl sulfate and sodium p-styrene sulfonate. Among them, sodium p-styrene sulfonate is a reactive emulsifier, so the emulsifier itself is co-coallocated. It is very effective in stabilizing emulsions. If the amount of emulsifier added is less than the lower limit of 0.1 part, the concentration of emulsifiers will be below the critical micelle concentration, making it difficult to emulsify without producing micelles, or the particle size of the emulsion particles will become large, resulting in failure of the polymerization system. A uniform and stable emulsion cannot be obtained. On the other hand, if it exceeds the upper limit, that is, 1.0 parts, the particle size becomes small and the BDV i of '#Li decreases, making it unsuitable for enamel Ti and 4BL rivers, both of which are undesirable. The above-mentioned polybutadiene used as the graft polymer here is a graft type ABS.
One piece of resin graft polybutadiene latex (for example, trade name JSRO700 manufactured by Nippon Gosei Co., Ltd.) is particularly preferred. The amount of polybutadiene added is 1 to 2 parts per 100 parts of the above monomer in terms of solid content.
0 parts is appropriate. If the amount is less than this lower limit, the effect of using polybutadiene will not be recognized, and if it exceeds 20 parts, the heat softening temperature of the obtained wire 11 will decrease, making it unsuitable as an enameled electric wire. Monomers in the above polymerization system include vinyl acetate, acrylonitrile, methacrylate, styrene, p-methylstyrene, m-methylstyrene, 0-methylstyrene, methacrylic acid, methyl methacrylate, acrylic acid, ethyl acrylate, and acrylic #
Monomers such as kf-ropyl, butyl acrylate, vinylpyridine, acrylamide, N-methylolacrylamide, glycidyl methacrylate, etc. can be used in combination. In many cases, it is necessary to contain about 35 to 80 1% by weight of acrylonitrile (IJ) as the main component. Also, 10 to 50% by weight of styrene monomer
As a crosslinking component, N-methylacrylamide, acrylic acid (or methacrylic wjt) and glycidyl methacrylate are combined in a weight of 1 to 15% each, or N-methylolacrylamide is used as a soft component in an amount of 1 to 15%. , acrylic esters (ethyl acrylate, globil acrylate, butyl acrylate) of 3 to 25 tS are added to impart flexibility to the resulting polymer film and at the same time to adjust the particle size of the emulsion. In addition to the above monomers, vinyl acetate, hydroxyethyl methacrylate, acrylamide, and methacrylic acid are added to optimize the electrodeposited film as an insulating film for enamelled wires and to stabilize the emulsion. It is also preferable to add 1 to 20% by weight of a hexamer such as methyl to the copolymer composition.

If the amount of the crosslinking component added is less than 1% by weight, the crosslinked structure of the insulating film may be insufficient to cause seizure to the electric wire, making it impossible to obtain sufficient mechanical strength and thermal softening temperature.
If it exceeds 5 fold fILs, the VC1 combination system tends to coagulate during the polymerization reaction, making it impossible to obtain a stable emulsion, which is undesirable. The amount of acrylic acid ester added as a soft component is 3iii1. Under dusty conditions, the particle size of the emulsion particles increases and the emulsion becomes unstable.
On the contrary, if the particle size exceeds 51 gk, the particle size becomes smaller, causing problems such as a decrease in the withstand voltage of the electrodeposited enameled wire.

The present invention will be explained in more detail with reference to Examples below.
After sufficient computer substitution while heating to ℃, add surfactant. Next, polybutadiene latex was added and thoroughly stirred, and then 100 parts by weight of monomers having the composition shown in the following table were added, and an initiator dissolved in ion-exchanged water was separately added dropwise.

The reaction was carried out in a nitrogen atmosphere at a reaction temperature of 75 to 85° C. for about 3 hours, and upon completion of the reaction, the mixture was immediately cooled and filtered through a 100-mesh wire gauze to obtain a varnish. Each of the obtained varnishes was used to actually electrodeposit I/C wires, and the general characteristics of the electrodeposited wires were evaluated (
The results according to the JIS standard "Enamelled copper wire and aluminum wire test method" are shown in the same table. For comparison, electrodeposited varnishes were prepared by ordinary emulsion polymerization with the composition shown in the same table, and the process was carried out in the same manner as in the above examples, and the properties are shown in the table. According to the results in the same table, the comparative example, which was not based on the duraft copolymerization system, was clearly inferior to the wire coated with a percentage of 1% of the present invention, which used a varnish in which 1 graft was combined with 1 liptadiene.

However, in the table above, Note 1: Wrap the wire 10 times around a round bar with a specified diameter, and visually inspect the coating for cracks.

Note 2 Due to the adhesion of the stretch wrapping film, the wire can be stretched rapidly (approximately 4 tones/see
), use a magnifying glass (15x magnification) to check whether there are any cracks in the film where the conductor can be seen.

E3 Fix both ends of the wire with the number of twists 41m and the distance 250cm, twist the koji by rotating one end in the same direction at a rate of 30 to 60 times per minute, and calculate the number of times it takes to visually see the conductor. Examine the adhesion of the film.

Note 4 Fold an 8DV 300cm test piece in two and apply the specified tension while twisting the approximately 120-length section by the specified number, then remove the tension and cut the folded part. This 2
After applying a voltage with a waveform close to a 60 (!/ISO sine wave) between the main wires, the test property 5 heat shock is tightly wound around a specified round bar 10 times.

Heat to the specified temperature for 1 hour, and after returning to room temperature, examine whether or not cracks occur in the film.

Agent 1 Nobuo Nobu -

Claims (1)

[Claims] (To 100 parts by weight of a monomer having unsaturated bonds in 11 molecules, 1 to 20 parts by weight of polybutadiene is added and combined in the presence of an initiator and an emulsifier) A method for producing a one-line electrodeposition paint characterized by: (2) using acrylonitrile and styrene yarn as monomers as main components, and in addition to reactive monomers as crosslinking components and for stabilizing the emulsion; Before using the acrylic acid ester type 7mer as part of the ingredients (1
) A method for producing a 1 mm electric paint as described in item 2. (3) As a surfactant to stabilize emulsions. 1 for electric wires described in the preceding paragraph (1), which includes the addition of sodium styrene sulfonate, which is a reactive surfactant.
Method of manufacturing first paint.