JPS5851409A - Insulated wire - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to an insulated wire.

Currently, as electrical insulating varnishes, especially varnishes for enameled wires, polyester varnishes have a relatively good balance of mechanical properties, electrical properties, and heat resistance.

It is widely used because it is harvested.

However, in recent years, as electric equipment has become smaller and lighter, there has been a demand for enamelled wire varnishes that have even better heat resistance and freon resistance. Varnishes for enameled wire with good heat resistance and Freon resistance include varnishes with high heat resistance such as polyimide varnish and polyamideimide varnish, but varnishes with high heat resistance such as N-methylpyrrolidone (NMP) etc. The resin itself is expensive, and there is a big problem in terms of cost. Therefore, in order to improve the heat resistance of polyester-based varnishes for enameled wires, so-called polyester imide varnishes containing imide groups as part of the resin component have been proposed. However, although polyesterimide has improved heat resistance compared to polyester, it has drawbacks in heat softening property and 7 leon resistance, and is not as good as KFi such as polyamideimide.

Therefore, many studies have been conducted to solubilize polyamide-imide varnish with excellent heat resistance in general-purpose solvents such as cresol (for example, Japanese Patent Publication No. 46-29730,
Special Publication Showa 49-30711. Publication No. J, Special Publication 1986-20
993, Japanese Patent Publication No. 53-47157). But heat resistant.

Freon Resistance 9 A resin with well-balanced mechanical properties and electrical properties has not yet appeared.

The present inventors have conducted intensive studies on heat-resistant resins that can be used in cresol-based solvents, and as a result, a part of the polyamide-imide resin component, which can only be synthesized in N-methylpyrrolidone, is soluble in cresol-based solvents. The present invention has been completed based on the use of a so-called solubilizing component as well as a branching component in order to maintain and improve heat resistance.

The present invention provides an aromatic diisocyanate, a lactam, a polycarboxylic acid having an acid anhydride group, and the general formula (X)rR
-fY)n (X hacalho*syl group.

Y is a carboxyl group, hydroxyl group or amino group, and R is an aromatic, aliphatic, alicyclic or heterocyclic residue.

n is an integer of 1 or more].

The lactam is in the range of 20 to 90 equivalents of the total incyanate equivalent, and the compound represented by the above general formula is added in an amount of 1 to 20 equivalents, the carboxyl group of which is in the range of 1 to 20 equivalents based on the carboxyl group and all the acid anhydride groups in the entire reaction system. The present invention relates to an insulated wire formed by coating and baking a resin composition containing a polyamideimide resin soluble in a cresol solvent, which is obtained by reacting in the presence of a cresol solvent.

The branching component represented by the general formula Any material may be used as long as it also has other functional groups that can serve as branching components.In consideration of flexibility, heat resistance, freon resistance, etc., i is a diisocyanate trimer 1, such as tolylene diisocyanate, inphorone diisocyanate/n trimer. For example, polyimide polycarboxylic acid is used, and trimesic acid, tris(2-carboxyethyl)in cyanurate, etc. are used.The diincyanate trimer is It can be prepared by a known method, for example, the method described in Japanese Patent Application No. 148820/1982.

The carboxyl group of the branching component represented by the above general formula is used in an amount of 1 to 20 equivalent percent based on the carboxyl group and acid anhydride group of the entire reaction system. If it is too large or too small, a well-balanced property of heat resistance and flexibility will not be exhibited. If the amount is too large, the degree of branching may increase and gelation may occur during synthesis. Similarly, lactams are important raw materials for cresol solvent solubilization.

In general, anything that reacts with an incyanate group or an acid anhydride group and is soluble in a cresol solvent may be used.
Considering solubility 1 reactivity and cost, Shin-Kapro 2
Kutam is preferred.

Although it depends on the intended use9, for example, in the case of a varnish for heat-resistant enameled wires, it is not necessary to add lactam in an amount equivalent to the incyanate group (e-caprolactam is considered to be difunctional). Heat-resistant.

Comprehensively considering flexibility, porosity and solubility, the range is 20 to 90 equivalent percent of the total incyanate equivalent,
substantially incorporated into the resin. If it is too large or too small, it will not be possible to obtain a product with a good balance between heat resistance and flexibility and excellent freon resistance.

Preferred aromatic diisocyanates include 4,4'-diphenylmethane diisocyanate, 44'-diphenyl ether diisocyanate, tolylene diisocyanate, and xylylene diisocyanate. A mixture of these aromatic diisocyanates may be used.

As a polycarboxylic acid having an acid anhydride group.

There is no particular limitation as long as it is a carboxylic acid or a derivative thereof having an acid anhydride group that reacts with an isocyanate group such as trimellitic anhydride. If necessary, a part of the carboxylic acid containing an acid anhydride group can be converted into pyromellitic dianhydride, butanetetracarboxylic dianhydride, bicyclo-[2
, 42]-octo-(7)-en-2:3,5:6-tetracarboxylic dianhydride and aliphatic or aromatic dibasic acid may be substituted. In general, it is preferable to use trimellitic anhydride as the main component in consideration of heat resistance, cost, etc. From the viewpoint of heat resistance, the amounts of incyanate component and acid component used are as follows:
The equivalent ratio of isocyanate groups to carboxyl groups and acid anhydride groups is selected to be 0.90 to 1.2.

In the reaction, all the raw materials may be charged at the same time, but in order to prevent turbidity, all the incyanate components should be combined with the general formula 〇Gr-R-(g). After charging the compound represented by, lactam and cresol solvent and reacting at 160 to 190°C for 1 to 3 hours.

Add polycarboxylic acid containing acid anhydride groups.

It is preferable to continue the reaction at 200 to 220°C for an additional 10 to 20 hours. The progress of the reaction can be determined by observing the generated carbon dioxide gas bubbles and the viscosity of the solution.

In addition to cresol, phenol,
Xylenol etc. can be used, and a mixed solvent may also be used. As part of the synthesis solvent, aromatic organic solvents with high boiling points such as xylene, Nl58EKIHISOL-100,150 (trademark of aromatic hydrocarbon manufactured by Nippon Petrochemical U), cellosolve acetate, etc. can also be used.

The polyamide-imide resin composition thus obtained is further diluted with a polar solvent such as the above-mentioned cresol solvent, N-methylpyrrolidone, dimethylformamide, dimethylacetamide, etc. to a resin content of 20 to 40% by weight for insulation. Used as a varnish for electric wires. In this case, Xyrezi, Nl8SEKIHI80L is used as a co-solvent.
-100, cellosolve acetate, etc. may be used in combination. The insulated IM produced using the varnish thus prepared exhibits good heat resistance, freon properties, and flexibility, and can be put to practical use as a heat-resistant insulated wire.

Of course, various thermosetting resins are used as curing agents.

Various metal salts may be added as leveling agents.

By adding epoxy resin to the polyamide-imide resin in the present invention, the appearance of the wire and the insulated wire are significantly improved.
High-speed workability is also improved.

Examples of epoxy resins include bisphenol-based epoxy resins such as Shell Co.'s product names, Epicoat 828, 1001, 1004.1007, etc., Dow Chemical Co.'s product names, novolac type epoxy resins such as DEN438, and Shikoku Kasei products. Heterocycle-containing epoxy resins such as TEPIC (glycidyl isocyanurate).

An alicyclic epoxy resin such as CH221 (trade name, manufactured by UCC Corporation) can be used, and there is no restriction on the epoxy resin used. Although the mixing ratio of the epoxy resin varies depending on the type, it is preferably about 1 to 30% by weight based on the resin content in the varnish. As a mixing method, the epoxy resin to be mixed may be dissolved in cresol in advance and added to the polyamide-imide resin, or the epoxy resin may be directly added dropwise to the heated polyamide-imide resin solution. In order to avoid thickening over time after addition of the epoxy resin, it is preferable to add K immediately before use.

By adding an alkoxy-modified amino resin to the polyamide-imide resin in the present invention, the appearance of the insulated wire is significantly improved and high-speed workability is also improved.

Alkoxy-modified amino resins are produced by addition-condensation reaction of formaldehyde or paraformaldehyde with amine compounds such as methyl, amine, benzoguanamine, and urea.
It may be one in which the methylol group is appropriately alkoxylated with an alcohol such as methanol, ethanol, propatool or butanol, and may be a co-condensate or a mixture.

The reason is unknown, but butylated benzoguanamine
Alkoxy-modified benzoguanamine formaldehyde resins such as formaldehyde resins are effective. These effects of addition are remarkable in the resol-soluble polyamide-imide resin of the present invention, and such effects are not observed in existing polyamide-imide resins that are soluble in N-methylpyrrolidone-based solvents. What is the mixing ratio?

Composition of alkoxy-modified amino resin to be mixed.

Although it varies depending on the molecular weight and functional groups of the resin.

0.1 to 20 weight 961 to the resin content in the varnish! degree is preferred. As a mixing method, the alkoxy-modified amino resin solution to be mixed may be dissolved in cresol in advance and added to the polyamide-imide resin, or the alkoxy-modified amine resin may be directly added to the heated polyamide-imide resin solution. The solution may be added dropwise. The temperature during mixing was in the range of room temperature to 200°C, without phase separation.

Any temperature is sufficient as long as uniform mixing is possible.

By adding phenol formaldehyde resin to the polyamide-imide resin in the present invention, the appearance of the insulated wire is significantly improved. Modified phenol formaldehyde resin etc. can be used.
There is no KflJ Kuma of that type. Examples of modified phenol formaldehyde resins include amino compound-modified phenol formaldehyde resins such as melamine-modified phenol formaldehyde resin, benzoguanamine-modified phenol formaldehyde resin, and urea-modified phenol formaldehyde resin, and the amino compound may be the alkoxy-modified amino resin described above. .

The mixing ratio of phenol formaldehyde resin varies depending on the molecular weight and the type of functional groups contained.

It is preferably about 0.1 to 30% by weight based on the resin content in the varnish. As a mixing method, the phenol formaldehyde resin to be mixed may be dissolved in cresol in advance and added to the polyamide-imide resin, or the phenol formaldehyde resin may be directly added dropwise to the heated polyamide-imide resin solution. good.

By adding a polyinocyanate having an incyanurate ring to the polyamide-imide resin of the present invention, further improved high-speed workability can be obtained. The polyisocyanate having an isocyanurate ring may be one obtained by trimerizing a polyisocyanate compound; Preference is given to polyisocyanate mixtures having trimers or incyanurate rings containing trimers.

The amount of polyisocyanate having an incyanurate ring to be added depends on the polyfunctionality of the polyisocyanate to be added, but for wire enamel, it is 1 to 20 weight q4 grains based on the resin content in the varnish. preferable. Phenol in advance.

A mask made of cresol, C-CabCI2cutam, etc. may also be used. As for the addition method, it may be added to the polyamide-imide resin at room temperature, or it may be added directly to the heated polyamide-imide resin solution.

By adding a polyester resin to the polyamide-imide resin in the present invention, the curability is significantly improved.

The polyester resin is not particularly limited as long as it has an OH residue, but it is preferable to use terephthalic acid and/or isophthalic acid as the acid component.

In the production of polyester resins, it is preferable to use terephthalic acid and/or isophthalic acid as the acid component, including lower alkyl esters thereof such as dimethyl terephthalate and monomethyl terephthalate.

Diethyl terephthalate, dimethyl isophthalate.

Diethyl isophthalate may also be used.

Condensates of terephthalic acid and/or isophthalic acid with glycol, such as polyethylene terephthalate, polyethylene phthalate, etc., may also be used.

Of course, it is also possible to use acids such as adipic acid, succinic acid, phthalic acid, trimellitic anhydride, maleic acid, and imidodicarboxylic acid represented by general formula (1), which are commonly used in electrical insulating varnishes. .

11...Song...(1) 〇 The imidodicarboxylic acid represented by the general formula (1) is 1. For example, as described in Japanese Patent Publication No. 51-40113, about 2 mol of trimellitic anhydride per 1 mol of diamine. Obtained by reacting. The diamine used is 4.4'-
Diaminodiphenylmethane, m-phenylenediamine,
p-phenylenediamine, 1,4-diaminonaphthalene, 44'-diaminodiphenyl ether, (4I-dimethylhbutamethylenediamine, hemethylene diamine, 44'-dicyclohexylmethanediamine, diaminodiphenyl sulfone, etc.) are used.Diamine Needless to say, imidodicarboxylic acid obtained by using a diisocyanate instead of is also used.

Polyhydric alcohol is used as the alcohol component used in the production of the above-mentioned polyester resin having hydroxyl groups. Dihydric alcohols include ethylene glycol, diethylene glycol, neopentyl glycol, 1.4
-butanediol, 1.6-hexanediol, 1.4
-Cyclohexane dimetatool, etc., and trihydric or higher alcohols include glycerin, trimethylolpropane, tris(2-hydroxydiethyl)in cyanurate,
Pentaerythritol etc. are used. From the viewpoint of heat resistance, it is preferable to use tris(2-human xyethyl) isocyanurate.

The amount of polyester resin added is preferably about 1 to 300% by weight based on the resin content of polyamide iodine in the varnish.

By adding an organic acid metal salt to the polyamide-imide resin of the present invention, the appearance of the insulated wire is significantly improved.

Examples of organic acid metal salts include dibutyltin laurate, dibutyltin acetate, manganese acid/manganese acid,
Examples of dryers include manganese octenoate, cobalt naphthenate, cobalt octenoate, zinc naphthenate, zinc octenoate, and the like, and one or more of these may be used.

The organic acid metal salt preferably has Fio, 0 based on the resin content.
1 to 10% by weight, more preferably 0.1 to 5% by weight.

The mixing of the organic acid metal salt and the polyamide-imide resin is not particularly limited, as long as it is carried out at a temperature from room temperature to 200'C so as to ensure uniform mixing.

These additives may be used alone.

May be used in combination. When used in combination, the individual effects of each are synergized. As a preferred combination when mixed and used.

Organic acid salt of Zn and phenol formaldehyde resin, phenol formaldehyde resin and alkoxy-modified amino resin, organic acid salt of Zn and alkoxy-modified amine resin, epoxy resin and phenol formaldehyde resin, polyisocyanate with incyanurate ring and phenol poly/ Examples include combinations of I and A fulldehyde resins, organic acid salts of Zn, phenol formaldehyde resins and alkoxy-modified amino resins.

In addition, other additives other than these epoxy resins, alkoxy-modified amino resins, phenol formaldehyde resins, polyisocyanates having incyanurate rings, polyester resins, and organic acid metal salts include polyethers, polyamides, polyamideimides, polyimides, Polyhydantoin, polysulfone, guanidine carbonate.

It can also be modified using benzotriazole, polyesterimide, polyesteramide, furan resin, etc. For example, from tris(2-hydroxyethyl)in cyanurate, ethylene glycol, tris(2-hydroxyethyl)in cyanurate, ethylene glycol, terephthalic acid dimethyl ester, 4,4'-diaminodiphenylmethane, trimellitic anhydride. Manufactured polyesterimide, 6-nylon.

Examples include polyamides such as a6-nylon and 12-nylon. These additives are preferably used in an amount of 0.1 to 30% by weight based on the resin content. Further, as a curing catalyst, tertiary amines such as triethylamine, triethylenediamine, N-methylmorpholine, N,N-dimethylethanolamine, and dimethylaniline are used.

It can also be modified by adding alcohols such as tetrabutyl titanate and tetrapropyl titanate.

When using a mixture of additives, it is preferable that the total amount of additives to the resin content does not exceed 25 parts by weight.

In addition to the polyamide-imide resin in the present invention, an epoxy resin, an alkoxy-modified amino resin, and a phenol formaldehyde resin may be used as necessary.

A resin composition containing one or more of a polyisocyanate having (isocyanurate) II, a polyester resin, and an organic acid metal salt is baked onto a conductor to form an insulated wire. The resin composition of the present invention is used as a varnish for electric wires.

When producing an insulated wire, the above resin composition is applied 3 to 15 times by die drawing or felt drawing. There are no particular restrictions on the baking temperature.

It is usually baked at a temperature of about 250 to 500 degrees Celsius. Especially the insulated wires obtained in this way.

Excellent heat resistance, freon resistance, and flexibility.

Of course, this is common practice in this industry.

Even when the above-mentioned composition is used as a part of a double-coated wire with a resin such as polyester, polyesterimide, formal, etc., an insulated wire with excellent heat resistance, resistance, and flexibility can be obtained.

The present invention will be explained by means of comparative examples and examples.

Comparative Example 1, (1) Synthesis of polyimide polycarboxylic acid Tolylene diisocyanate 300 xylene
3002-dimethylamine ethanol (catalyst)
o, ta゛ Cresol 150
0 Trimellitic anhydride 3429 The above ingredients other than trimellitic anhydride and cresol were placed in a four-lobe flask equipped with a temperature needle and a stirrer, and the mixture was heated for 1 hour in a nitrogen stream.
Raise the temperature to 40℃.

The reaction was continued at the same temperature until the content of incyanate groups (initial concentration: 48 weight percent) reached 25 weight percent. The infrared spectrum of this substance has l 71 Qm
Absorption of an isocyanate ring was observed in 225 QQft-'' and 141Qm-', and absorption of an incyanate group was observed in 225QQft-''.

Cresol 1500F was added to the trimer thus obtained.
was added to make a homogeneous solution, the temperature was raised to 140°C again, trimellitic anhydride 3419 S) was added, and while xylene was distilled off, the decarboxylation imidization reaction was carried out and the temperature was raised to 200°C.
The reaction was continued until the temperature rose to 0.degree. C. and no carbon dioxide gas was produced.

(2) Synthesis of cresol-soluble polyamideimide 1 resin Trimellitic anhydride 85.4 0.89g
- Caglolactam 84.8 1.5 Cresol 250 Temperature needle of the above components except trimellitic anhydride.

The mixture was placed in a four-loaf flask equipped with a stirrer and a fractionating tube, and the temperature was raised to 180°C in a nitrogen stream and the reaction was carried out for 90 minutes.Next, trimellitic anhydride was added and the temperature was raised to 210°C. The reaction was continued at 210° C. for 15 hours. Cresol resin concentration 25% by weight Kl! The varnish was obtained by making il. The viscosity of this material is 65 poise (30
°C). 1780cFR for infrared absorption spectrum
Absorption of imide group was observed in ``-'', and absorption of amide group was observed in ``165051-''.

Comparative Example 2 (1) Synthesis of polyimide polycarboxylic acid xylene
3002-dimethylamine ethanol 0.9 trimellitic anhydride 342
9N-Methyl-2-pyrrolidone 56&0 The above components other than trimellitic anhydride and N-methyl-2-pyrrolidone were reacted in the same manner as in Comparative Example 1 (1) until the content of isocyanate groups became 25% by weight. Ta. N-methyl-2-pyrrolidone 56a and OF were added to the trihonarye obtained in this way, and trimellitic anhydride 342.9P was further added, the temperature was raised to 150°C, and carbon dioxide gas was added. The reaction was continued until no more occurred.

(2) Synthetic component of cresol-soluble polyamideimide resin Durham equivalent trimellitic anhydride 90,2 α94ε-
Caprolactam 84°8 1.50 Cresol 250.0 Similarly to Comparative Example 1, a cresol-soluble polyamide-imide resin was synthesized using the above components.

The obtained original resin was adjusted to a resin concentration of 25% by weight with cresol to obtain a varnish. The viscosity of this product is 60 poise (30°C), which makes it unpleasant.

Example 1 Imidopolycarboxylic trimellitic anhydride 86.4 0.906
-Caprolactam 45.2 0.80 Cresol 250 A varnish was synthesized in the same manner as in Comparative Example 1 (2), and the resin concentration was adjusted to 25% by weight with cresol. The viscosity of this product was 45 poise (30°C). In the infrared absorption spectrum, an imide group absorption was observed at 1780 aw-'' and an amide bond absorption was observed at 1650 cns-''.

Example 2 Component Durham Equivalent Poly 82LOO, 1 synthesized in (1) of Comparative Example 2
1 Imide polycarboxylic acid composition trimellitic anhydride 86.4 0.906
-Caprolactam 39.4 α70 Cresol 350 A varnish was synthesized in the same manner as in Comparative Example 1 (2) and adjusted to a resin concentration of 25% by weight with cresol.

The viscosity of this product was 60 poise (30°C). In the infrared absorption spectrum, the absorption of the 1780cH1''19 imide group and the absorption of the amide group of 1650α-1 are both Kia!
I was caught. Further to the resulting varnish.

As a curing agent, alkoxy-modified amino resin ML-20 (
Hitachi Chemical IEKK) aO), z Bicoat 10076, O?
and phenol formaldehyde resin PR-2084W
(Hitachi Chemical KK) 10. (Added l.

Example 3 Ingredients Durum equivalent trimesic acid 5.6 0.08
Trimellitic anhydride 91.2 0.951
-Caprolactam 33.9 0.60 Cresol 170.5 Xylene
The above ingredients except 5.0 trimesic acid and trimellitic anhydride were placed in a 94 flask equipped with a thermometer, a stirrer, and a fractionator tube, and the temperature was raised to 180°C in a nitrogen stream.
The reaction was carried out for 90 minutes. Next, the temperature is lowered to 160°C, trimesic acid and trimellitic anhydride are added, and the temperature is increased to a temperature at which cresol refluxes. 10 at this temperature
Advance the time reaction9. The resin concentration was adjusted to 23% by weight with cresol to obtain a varnish. The solution viscosity of this product is 83 poise (30°C), and the reduced specific viscosity is 0.28 (0,
5? /dimethylformamide 100ml solution). To the obtained varnish, an imide-modified polyester resin Isomid (Schenectady Co., Ltd.) 60.0) and zinc 7thenate α5f were further added as a curing agent.

Example 4 Trimesic acid 14.0 G, 2 trimellitic anhydride 76.8 0.8-monocaglolactam 319 0.60 Cresol 159.0 Xylene
&0 Nine varnishes were obtained by adjusting the resin concentration to 24% by weight. The solution viscosity of this product is s3. 'o poise.

(30°C), and the reduced specific viscosity was 0.27 (0.5?/dimethylformamide 100-solution). Bisphenol epoxy resin Epicoat 1001 (manufactured by Shell Co., Ltd.) 4017F was added to the obtained varnish as a hardening agent.

Example 5 Trimellitic anhydride 89.3 0.934
4'-diphenylmethane 125.0 1.0
0 Socyanate-1-Caglolactam 3 & 9 0.60 Cresol 210.0 Xylene &0 Synthesized in the same manner as in Example 3 except for replacing with trimesic acid wotris (2-carboxyethyl) isocyanurate, and the resin concentration was adjusted to 25 weight percent. The solution viscosity of the varnish was 45 poise (30°C).

Example 6 4.4'-diphenylmethane 12&0 1.
0G Socyanate trimellitic anhydride 8&3 α926-capro2cutam 319 0.60 Cresol 180.0 Synthesized in the same manner as in Comparative Example 1 (2), and then polyester resin was added. The viscosity of this product was 85 poise (30° C.) when adjusted with K-cresol (resin concentration 30% by weight).

Table 4 shows the characteristics of the nine insulated wires obtained or prepared using varnish.
Dangerous.

p・ The characteristic test was conducted according to JIS C3003.

(However, the cut-through load was 2 noodles.) Compared to the cresol-soluble polyamide-imide synthesized using 6-caprolactam in an equivalent amount of 1.5 times the total amount of incyanate in Comparative Example 1.2, the content of 9-branched acids was The electric wires of Examples 1 to 6 were synthesized by paying attention to the respective contents of 6-caprolactam and 6-caprolactam, and all of them have excellent heat resistance (cut-through), flexibility, and freon resistance.

Claims (1)

[Claims] 1. Aromatic diisocyanate, lactam, polycarboxylic acid having an acid anhydride group, and general formula (X) r-'ELH
Compounds represented by [X is a carboxyl group, Y is a carboxyl group, hydroxyl group, or amino group, R is an aromatic, aliphatic, alicyclic, or diatomic group residue, and n is an integer of 1 or more] of. The lactam is in the range of 20 to 90 equivalents of the total incyanate equivalent, and the compound represented by the above general formula has a carboxyl group in the range of 1 to 20 equivalents with respect to the carboxyl group and acid anhydride group of the entire reaction system. An insulated wire obtained by coating and baking a resin composition containing a polyamide-imide resin soluble in a cresol solvent obtained by reacting the resin composition in the presence of a cresol solvent.