JPH10265717A - Coating material for insulation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a coating material for insulation capable of forming a coated membrane not generating a pinhole and excellent in heat resistance and moist heat resistance by containing specific ratios of specific polyesterimide resin, epoxy resin, polyvinylformal resin and stabilized isocyanate compound. SOLUTION: This coating material for insulation contains (A) 100 pts.wt. polyesterimide resin obtained by reacting divalent carboxylic acids containing an imide group of a five-membered ring and an aromatic polyvalent carboxylic acids with a polyhydryl alcohol in 1.2-3.0 equivalent ratio range of total alcohol component/total acid component, (B) 10-60 pt.wt. epoxy resin such as a bis- phenol A type, (C) 10-60 pt.wt. polyvinylformal resin, and also (D) 50-500 pt.wt. stabilized isocyanate compound based on 100 pts.wt. total resin component. Further, it is preferable that the component (D) is an aromatic polyisocyanate (a block material) having >=2 benzene rings in a molecule.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulating paint for forming an insulating coating film having excellent heat resistance and wet heat resistance.

[0002]

2. Description of the Related Art In recent years, with the miniaturization, high performance, and sealing of electric equipment, the operating temperature of the electric equipment has often increased in an atmosphere in which moisture has been confined inside the electric equipment. There has been an increasing demand for insulating paints that form heat-resistant and moisture-heat-resistant coatings used in the manufacture of insulated wires to improve the reliability of the products.

[0003] In response to the above requirements, insulated wires using a conventional polyester can provide an insulated wire having a heat resistance of class F (155 ° C), which satisfies the heat resistance requirement, but has a requirement for wet heat resistance. Not satisfied.

Further, insulated wires using a conventional polyurethane insulating paint (usually referred to as polyurethane insulated wires).
The same applies when other insulating paints are used. )
Although the moisture and heat resistance is better than the polyester insulated wire, it is still insufficient for the required level, and the heat resistance is only class E (120 ° C.). Therefore, in order to improve the heat resistance of the polyurethane insulated wire, an insulating paint using heat-resistant polyesterimide urethane has been developed, and has heat resistance of Class B (130 ° C.) to Class F (155 ° C.) using the same. Insulated wires have been put into practical use. This insulated wire is
Although the heat resistance is satisfactory, the wet heat resistance is at the same level as the conventional polyurethane insulated wire, and does not satisfy the requirements.

[0005]

By the way, in the case of the conventional insulating paint using polyesterimide, H class (180
Insulated wires satisfying the heat resistance of (.degree. C.) and the required wet heat resistance can be obtained, but the film formed from this insulating paint has the drawback that pinholes are remarkably generated during elongation. On the other hand, in the case of the conventional polyamide-imide insulating paint, the insulated wire using the same satisfies the demands for heat resistance and heat and humidity resistance, but the process is complicated due to poor workability in the manufacture of the insulated wire, and the production cost is extremely expensive. It has the disadvantage of becoming complicated.

Accordingly, an object of the present invention is to provide an insulating paint which overcomes the above-mentioned drawbacks of the conventional insulating paint, has excellent heat resistance and wet heat resistance, and is capable of producing an insulated wire having a coating which does not generate pinholes. To provide. The inventor of the present invention has intensively studied to achieve this object and completed the present invention.

[0007]

The above object is achieved by the present invention described below. That is, the present invention relates to (A) a polyesterimide resin 1 having a five-membered imide group in the molecule.
(B) 10 to 60 parts by weight of epoxy resin
Parts by weight, (C) 10 to 60 parts of polyvinyl formal resin
It is an insulating paint characterized in that it contains the stabilized isocyanate compound in a proportion of 50 to 500 parts by weight based on 100 parts by weight of all resin components.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the present invention will be described in more detail with reference to embodiments of the present invention. The polyesterimide resin (A) having a five-membered ring imide group in a molecule, which is a main component of the insulating paint of the present invention, is a known resin conventionally used in paints for insulated wires, and is a five-membered ring. Is a polyesterimide resin obtained by esterifying a dihydric carboxylic acid, an aromatic polycarboxylic acid and a polyhydric alcohol having an imide group of the formula (1) according to a conventional method.

A preferred polyester imide resin in the present invention comprises at least one divalent carboxylic acid containing a 5-membered imide group in an amount of at least 10 equivalent%, preferably 20 to 30 equivalent% of the total acid components. As the polyhydric alcohol, at least one type of dihydric alcohol / at least one type of trihydric or higher polyhydric alcohol (equivalent ratio) is 0.1 to 2.5, preferably 0.1 to 2.5. Used at a ratio of 2.0, and total alcohol component / total acid component (equivalent ratio)
The main component is obtained by reacting at a ratio of 2 to 3.0, preferably 1.5 to 2.5.

When the amount of the divalent carboxylic acid containing a 5-membered imide group is less than 10% by weight based on the total acid components, the heat resistance of the obtained resin is insufficient. On the other hand, if the equivalent ratio of the divalent alcohol to the trivalent or higher polyvalent alcohol is less than 0.1, it is difficult to synthesize the resin, and if it exceeds 2.5, the heat resistance of the obtained resin is poor. Will be enough. The reaction of all the alcohol components in excess with respect to the total acid components to form a polyesterimide resin having a hydroxyl group at the terminal is carried out by reacting the hydroxyl group at the terminal with the stabilized isocyanate compound at the time of baking. This is for crosslinking.

The divalent carboxylic acid containing a 5-membered imide group used in the present invention includes, for example, those obtained by reacting the following (a) and (b) by a conventionally known method. .

(A) In addition to a five-membered carboxylic acid anhydride,
Aromatic carboxylic anhydride containing one carboxy group. For example, trimellitic anhydride, hemi-mellitic anhydride, naphthalene tricarboxylic anhydride, diphenyltricarboxylic anhydride, benzophenone tricarboxylic anhydride and the like can be mentioned. Particularly useful is trimellitic anhydride.

(B) An aromatic diamine having a primary amino group. For example, 4,4'-diaminodiphenylmethane,
4,4'-diaminodiphenyl ether, 4,4'-
(Or 3,3 ′-) diaminodiphenyl sulfone, p-
(Or m-) phenylenediamine and the like. Particularly useful is 4,4'-diaminodiphenylmethane. Further, instead of (b), p- (or m-) phenylene diisocyanate, 2,4- (or 2,6-) tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate A divalent carboxylic acid containing a 5-membered imide group can also be obtained by using a polyisocyanate such as

The most preferred divalent carboxylic acid containing a 5-membered imide group is trimellitic anhydride 2
Is a five-membered imido acid obtained by reacting 1 mol of diaminodiphenylmethane with 1 mol of diaminodiphenylmethane.

The aromatic polycarboxylic acids (containing no five-membered imide group) used in the present invention include, for example,
Terephthalic acid, isophthalic acid, phthalic anhydride, dimethyl terephthalic acid, dimethyl isophthalic acid, trimellitic acid, trimellitic anhydride, naphthalene tricarboxylic anhydride, diphenyl tricarboxylic anhydride, benzophenone tricarboxylic anhydride, pyromellitic dianhydride Anhydrous,
Aromatic carboxylic acids such as naphthalenetetracarboxylic dianhydride and benzophenonetetracarboxylic dianhydride; anhydrides thereof; and lower alkyl (having about 1 to 6 carbon atoms) esters of these carboxylic acids. These can be used alone or in combination of two or more.

Among the polyhydric alcohols used in the present invention,
As the divalent alcohol, for example, ethylene glycol
And aliphatic diols such as propanediol and hexanediol. Examples of the trivalent or higher polyhydric alcohol include aliphatic alcohols such as glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol, and tris- (2-hydroxyethyl) isocyanurate. These polyhydric alcohols can be used alone or in combination of two or more.

As a method for synthesizing the polyesterimide resin of the present invention using the above-mentioned raw materials, for example, the following method can be mentioned. (1) Aromatic carboxylic anhydrides, aromatic diamines and polycarboxylic acids having one carboxyl group in the presence of cresol solvents such as cresol, phenol and xylenol , Divalent alcohol and trivalent or higher polyvalent alcohol are mixed at once, and in this system, 120 to 160
A method in which an imidation reaction (formation of a five-membered ring imidic acid) is performed at a temperature of 200 ° C., the temperature is increased to 200 ° C., and a polyesterification reaction is performed at a temperature of 200 to 240 ° C. for 2 to 5 hours.

(2) An aromatic carboxylic anhydride having one carboxyl group and an aromatic diamine are mixed in the presence of a cresol-based solvent such as cresol, phenol and xylenol; After performing an imidation reaction at 120 to 160 ° C., an aromatic polycarboxylic acid, a divalent alcohol, and a trivalent or higher polyhydric alcohol are added, and the temperature is raised to 200 ° C., and further 200 hours. A method in which the reaction is carried out at a temperature of from 240 to 240 ° C. for 2 to 5 hours.

(3) First, a polyester intermediate comprising an aromatic polycarboxylic acid, a dihydric alcohol and a trivalent or higher polyhydric alcohol is synthesized, and the above-mentioned cresol-based solvent, A method in which an aromatic carboxylic anhydride and an aromatic diamine are added, the temperature is raised to 200 ° C., and the reaction is further performed at 200 to 240 ° C. for 2 to 5 hours.

(4) The aromatic carboxylic anhydride and the aromatic diamine are mixed in the presence of the above-mentioned cresol-based solvent, and an imidization reaction is carried out at 120 to 160 ° C.
Previously synthesized aromatic polycarboxylic acids, divalent alcohols
And adding a polyester intermediate comprising a polyhydric alcohol having a valence of 3 or more, raising the temperature to 200 ° C., and further performing the reaction at 200 to 240 ° C. for 2 to 5 hours.

The insulating paint of the present invention contains (A) a polyesterimide resin obtained above, (B) an epoxy resin, (C) a formal resin, and (D) a stabilized isocyanate compound in a predetermined ratio. It is.

As the epoxy resin (B) used in the present invention, for example, a bisphenol A type epoxy resin synthesized by a condensation reaction between bisphenol A and epichlorohydrin (for example, YD-001 manufactured by Toto Kasei Co., Ltd.) 01
1,014,017,019, etc. and Epicoat 1001, 1004, 1007, 1009 manufactured by Yuka Shell Epoxy Co., Ltd.
And bisphenol F-type epoxy resins (for example, YDF-170, 200 manufactured by Toto Kasei Co., Ltd.).
1, 2004 etc.), brominated epoxy resins (for example, YDB-400, 50 manufactured by Toto Kasei Co., Ltd.)
0, 700, etc. and Epicoat 10 manufactured by Yuka Shell Epoxy Co., Ltd.
45, 1050, YL903, etc.)
And the like.

The polyvinyl formal resin (C) used in the present invention is a resin obtained by acetalizing a polyvinyl alcohol resin with formalin. For example, commercially available products such as Vinylex F, K and L manufactured by Chisso Corporation Is mentioned.

As the stabilized isocyanate compound used in the present invention, an aromatic polyisocyanate having at least two benzene rings and / or a block body thereof are preferred. At least two isocyanate groups are required in the molecule to crosslink the polyesterimide resin of the present invention.

Examples of the aromatic isocyanate having at least two benzene rings and its block body include 4,4'-diphenylmethane diisocyanate (M
DI), naphthalene diisocyanate (NDI), vitriylene diisocyanate (TODI), trimer of tolylene diisocyanate (TDI), a compound obtained from TDI (3 mol) and trimethylolpropane (1 mol) (for example, Aromatic isocyanates such as Nippon Polyurethane Co., Ltd., etc., triphenylmethane triisocyanate and the like, and compounds obtained from MDI and xylenol (for example, Nippon Polyurethane Co. Millionate MS-
50), compounds obtained from MDI, aliphatic polyols and phenols (for example, Coronate 2503 manufactured by Nippon Polyurethane Co., Ltd.), and compounds obtained from a trimer of TDI and phenol (for example, Blocked aromatic isocyanates, such as Desmodur CT-Table manufactured by Bayer Corporation. In the block body, the blocking agent is not particularly limited, and for example, phenol, alkylated phenol, cresylic acid and the like are usually used.

Particularly preferred stabilized isocyanate compounds are diisocyanates (1) having two benzene rings in the molecule, and in particular, blocked stabilized isocyanates comprising 4,4'-diphenylmethane diisocyanate (MDI). Compound and a diisocyanate (2) having three benzene rings in the molecule, in particular, a blocked stabilized isocyanate compound (2) comprising a trimer of tolylene diisocyanate (TDI). Yes, (1) /
(2) The ratio (weight ratio) is preferably 20/80 to 90/10. When the ratio of (1) is higher than the above ratio, the heat and moisture resistance of the insulated wire coated and baked with the insulating paint of the present invention becomes insufficient, and when it is lower, the occurrence of elongated pinholes becomes remarkable, which is not preferable.

The insulating coating composition of the present invention comprises (B) 10 to 60 parts by weight, preferably 15 to 50 parts by weight, of an epoxy resin and (C) polyvinyl resin per 100 parts by weight of a polyesterimide resin. (D) stable formal resin in a proportion of 10 to 60 parts by weight, preferably 15 to 50 parts by weight, and 100 parts by weight of these resins (A), (B) and (C) in total. 50 to 5
It is contained in an amount of 00 parts by weight, preferably 80 to 400 parts by weight. If the content of each of the epoxy resin and the polyvinyl formal resin is less than 10 parts by weight, the heat and moisture resistance of the insulated wire using the insulating paint of the present invention will be insufficient, and if it exceeds 60 parts by weight, the heat resistance will be insufficient. If the content of the stabilized isocyanate compound is less than 50 parts by weight, crosslinking at the time of baking and curing the insulating paint of the present invention at the time of manufacturing an insulated wire is insufficient and a satisfactory insulating film cannot be obtained. Exceeding the part is not preferable because the crosslinking becomes excessive and the flexibility of the insulating coating is reduced.

Examples of the solvent used in the production of the insulating coating of the present invention include solvents having a phenolic hydroxyl group such as phenol, cresol and xylen, which are main solvents in the synthesis of the polyesterimide resin. It is preferable to combine diluents such as xylene and solvent naphtha, but they are used for baking paints such as N-methyl-2-pyrrolidone, dimethylacetamide, dimethylformamide, glycol ethers, alcohols and ketones. The solvent may be used as a diluent, or may be used by adding a part of the diluent such as xylene. The insulating paint of the present invention can be obtained by dissolving all the resin components and the stabilized isocyanate compound in the above-mentioned solvent.

When the insulating paint of the present invention is applied to a conductor and baked to produce an insulated wire, an effective amount of an organometallic compound is added to the insulating paint as a catalyst for dissociating the block of the stabilized isocyanate compound. Is preferable because the production speed of the insulated wire is increased and the surface smoothness of the insulated wire is further improved. Examples of the dissociation catalyst for these stabilized isocyanate blocks include metal salts of aliphatic or alicyclic carboxylic acids such as zinc, lead and manganese, dibutyltin dilaurate, dibutyltin diacetate and tertiary amine. Carboxylic acids. The addition amount of these dissociation catalysts is preferably 0.01 to 3.0% by weight, more preferably 0.05 to 2.0% by weight, based on the total amount of the stabilized isocyanate compound in the insulating paint. .

As long as the characteristics of the present invention are not lost, thermoplastic resins such as polyamide, polyester, and polysulfone, melamine resins, and phenolic resins may be used in the insulating coating of the present invention.
It is also possible to add thermosetting resins such as resin, dyes, pigments, lubricants, and other additives commonly used for insulating coatings.

[0031]

EXAMPLES The present invention will be described more specifically with reference to Reference Examples, Examples and Comparative Examples, but the present invention is not limited to these Examples. In the following text,%
The mixing ratio is based on weight unless otherwise specified.

Reference Example 1 A 5-liter flask equipped with a stirrer, a nitrogen inlet tube, a condenser, and a thermometer was charged with 703 g of phthalic anhydride (4.7 g).
5 mol), 186 g (3.0 mol) of ethylene glycol and 630 g (4.67 mol) of trimethylolpropane, and the temperature was raised while blowing nitrogen.
At 0 ° C., the distillation of water started and the reaction started. After the internal temperature was raised to 220 ° C. over 8 hours, the heating was stopped and the mixture was diluted with 376 g of cresol. After cooling to 100 ° C., 96 g (0.25 mol) of trimellitic anhydride and 4,4
49.5 g of 4'-diaminodiphenylmethane (0.12
(5 mol) was added, and the mixture was heated again and reacted at 150 ° C. for 2 hours to produce a divalent carboxylic acid containing a five-membered ring in the system. Thereafter, the mixture was heated to an internal temperature of 220 ° C., reacted for 5 hours, stopped heating, diluted with 1,128 g of cresol, and a polyesterimide resin (1) having a resin content of 50%.
Was obtained.

Reference Example 2 The amount of the starting compound used was 518 g (3.5 g) of phthalic anhydride.
Mol), 186 g (3.0 mol) of ethylene glycol,
630 g (4.67 mol) of trimethylolpropane, 853 g of cresol, 576 g of trimellitic anhydride
(1.5 mol), 297 g of diaminodiphenylmethane
(0.75 mol), and a solution of polyesterimide resin (2) having a resin content of 50% was obtained in the same manner as in Reference Example 1 except that the amount of cresol was changed to 1,138 g.

Reference Example 3 The amount of the starting compound used was changed to 370 g (2.5 g) of phthalic anhydride.
Mol), 186 g (3.0 mol) of ethylene glycol,
630 g (4.67 mol) of trimethylolpropane, 1,952 g of cresol, 960 g of trimellitic anhydride
(2.5 mol), 495 g of diaminodiphenylmethane
(1.25 mol), 434 g of cresol, Reference Example 1
In the same manner as in the above, a solution of a polyesterimide resin (3) having a resin content of 50% was obtained.

Reference Example 4 498 g (3.0 mol) of terephthalic acid, 186 g (3.0 mol) of ethylene glycol, 630 g (4.67 mol) of trimethylolpropane, 1,484 g of cresol,
768 g (2.0 mol) of trimellitic anhydride, 396 g (1.0 mol) of diaminodiphenylmethane, Crezo-
The resin content was 5 in the same manner as in Reference Example 1 except that
A solution of 0% polyesterimide resin (4) was obtained.

Reference Example 5 In the same manner as in Reference Example 1, except that 518 g of phthalic anhydride was used.
(3.5 mol), 496 g of ethylene glycol (8.0
Mol), 180 g (1.33 mol) of trimethylolpropane, 793 g of cresol, 57 g of trimellitic anhydride
6 g (1.5 mol), diaminodiphenylmethane 297
g (0.75 mol) and 1,058 g of cresol, a solution of a polyesterimide resin (5) having a resin content of 50% was obtained.

Reference Example 6 The same as Reference Example 1 except that 518 g of phthalic anhydride was used.
(3.5 mol), 372 g of ethylene glycol (6.1
Mol), 1,260 g of trimethylolpropane (9.3 g).
3 mol), 1,203 g of cresol, 576 g (1.5 mol) of trimellitic anhydride, 297 g (0.75 mol) of diaminodiphenylmethane, 1,604 g of cresol
As a result, a solution of a polyesterimide resin (6) having a resin content of 50% was obtained.

Reference Example 7 The amount of the starting compound used was changed to 518 g (3.5 g) of phthalic anhydride.
Mol), 23.3 g (0.375 mol) of ethylene glycol, 641 g (4.75 mol) of trimethylolpropane, 789 g of cresol, 57 g of trimellitic anhydride
6 g (1.5 mol), diaminodiphenylmethane 297
The reaction was carried out in the same manner as in Reference Example 1 as g (0.75 mol), but gelation was not able to obtain a solution of the polyesterimide resin (7).

Table 1 shows the ratio of the starting compound used and the ratio of the dicarboxylic acid containing a five-membered imide group in the above Reference Examples.
Shown in

[0040]

[Table 1]

Example 1 In a 1-liter flask equipped with a stirrer and a thermometer, a 50% solution of the polyesterimide resin (2) of Reference Example 2 was prepared.
00 g, 40 g of epoxy resin (Epicoat 1007: manufactured by Yuka Shell Co., Ltd.), 40 g of polyvinyl formal resin (Vinylec H: manufactured by Chisso Corporation), and stabilized isocyanate compound (Coronate 2503: manufactured by Nippon Polyurethane Co., Ltd.) 12
0 g of a stabilized isocyanate compound (Desmodur C
80 g of T-Stable (manufactured by Bayer AG) and 4 g of zinc naphthenate (8% zinc) were dissolved in 163 g of cresol and 113 g of xylene at an internal temperature of 80 ° C. to give a solid content (total resin content) of 50%. Paint was obtained.

Example 2 In a 1-liter flask equipped with a stirrer and a thermometer, a 50% solution of the polyesterimide resin (2) of Reference Example 2 was prepared.
00g, Epicoat 1007 (manufactured by Yuka Shell) 40
g, Vinylec H (manufactured by Chisso), 20 g, Coronate 2
503 (manufactured by Nippon Polyurethane), 120 g of Desmodur CT-Table (manufactured by Bayer), and 4 g of zinc naphthenate (8% zinc) are dissolved in 149 g of cresol and 107 g of xylene at an internal temperature of 80 ° C. And resin 5
0% paint was obtained.

Example 3 In a 1-liter flask equipped with a stirrer and a thermometer, a 50% solution of the polyesterimide resin (2) of Reference Example 2 was prepared.
00g, Epicoat 1007 (manufactured by Yuka Shell) 20
g, Vinilec H (manufactured by Chisso) 40 g, Coronate 2
503 (manufactured by Nippon Polyurethane), 120 g of Desmodur CT-Table (manufactured by Bayer), and 4 g of zinc naphthenate (8% zinc) are dissolved in 149 g of cresol and 107 g of xylene at an internal temperature of 80 ° C. And resin 5
0% paint was obtained.

Example 4 In a 1-liter flask equipped with a stirrer and a thermometer, a 50% solution of the polyesterimide resin (3) of Reference Example 3 was prepared.
00g, Epicoat 1007 (manufactured by Yuka Shell) 30
g, Vinilec H (manufactured by Chisso) 30 g, Coronate 2
503 (manufactured by Nippon Polyurethane), 80 g of Desmodur CT-table (manufactured by Bayer), and 4 g of zinc naphthenate (8% zinc) were dissolved in 149 g of cresol and 107 g of xylene at an internal temperature of 80 ° C. And resin 5
0% paint was obtained.

Example 5 In a 1-liter flask equipped with a stirrer and a thermometer, a 50% solution of the polyesterimide resin (2) of Reference Example 2 was prepared.
00g, Epicoat 1007 (manufactured by Yuka Shell) 30
g, Vinylek H (manufactured by Chisso) 30 g, Millionate MS-50 (manufactured by Nippon Polyurethane) 120 g, Desmodur CT-Stable (manufactured by Bayer) 80 g, and zinc naphthenate (zinc 8%) 4 g Cresol 149
g and 107 g of xylene at an internal temperature of 80 ° C. to obtain a paint having a resin content of 50%.

Comparative Example 1 In a 1-liter flask equipped with a stirrer and a thermometer, a 50% solution of the polyesterimide resin (2) of Reference Example 2 was prepared.
00g, Coronate 2503 (manufactured by Nippon Polyurethane)
120 g, Desmodur CT-Table (manufactured by Bayer) 80 g and zinc naphthenate (zinc 8%) 4 g were dissolved in cresol 110 g and xylene 90 g at an internal temperature of 80 ° C., and the resin content was 50%. Paint was obtained.

Comparative Example 2 In a 1-liter flask equipped with a stirrer and a thermometer, a 50% solution of the polyesterimide resin (1) of Reference Example 1 was prepared.
0 g, Epicoat 1007 (manufactured by Yuka Shell Co.), 30 g,
30 g of Vinylec H (manufactured by Chisso), 250 of Coronet
3 (manufactured by Nippon Polyurethane), 120 g of Desmodur CT-table (manufactured by Bayer), and 4 g of zinc naphthenate (8% zinc) were dissolved in 149 g of cresol and 107 g of xylene at an internal temperature of 80 ° C. And resin content 50%
Paint was obtained.

Comparative Example 3 A 50% solution of the polyesterimide resin (5) of Reference Example 5 in a 1 liter flask equipped with a stirrer and a thermometer was used.
0 g, Epicoat 1007 (manufactured by Yuka Shell Co.), 30 g,
30 g of Vinylec H (manufactured by Chisso), 250 of Coronet
3 (manufactured by Nippon Polyurethane), 120 g of Desmodur CT-table (manufactured by Bayer), and 4 g of zinc naphthenate (8% zinc) were dissolved in 149 g of cresol and 107 g of xylene at an internal temperature of 80 ° C. And resin content 50%
Paint was obtained.

Comparative Example 4 In a 1-liter flask equipped with a stirrer and a thermometer, a 50% solution of the polyesterimide resin (6) of Reference Example 6 was prepared.
00g, Epicoat 1007 (manufactured by Yuka Shell) 30
g, Vinilec H (manufactured by Chisso) 30 g, Coronate 2
503 (manufactured by Nippon Polyurethane), 120 g of Desmodur CT-Table (manufactured by Bayer), and 4 g of zinc naphthenate (8% zinc) are dissolved in 149 g of cresol and 107 g of xylene at an internal temperature of 80 ° C. And resin 5
0% paint was obtained.

Comparative Example 5 In a 1-liter flask equipped with a stirrer and a thermometer, a 50% solution of the polyesterimide resin (2) of Reference Example 2 was prepared.
00g, Epicoat 1007 (manufactured by Yuka Shell) 40
g, Vinylek H (manufactured by Chisso) 5 g, Coronate 25
03 (manufactured by Nippon Polyurethane) 120 g, Desmodur
80 g of CT-Stable (manufactured by Bayer AG) and 4 g of zinc naphthenate (8% zinc) were dissolved in 139 g of cresol and 102 g of xylene at an internal temperature of 80 ° C.
% Paint was obtained.

Comparative Example 6 In a 1-liter flask equipped with a stirrer and a thermometer, a 50% solution of the polyesterimide resin (2) of Reference Example 2 was prepared.
00g, Epicoat 1007 (manufactured by Yuka Shell Co., Ltd.), 5g,
40 g of Vinylec H (manufactured by Chisso), 250 of Coronet
120 g of Desmodur CT-table (manufactured by Bayer) and 4 g of zinc naphthenate (8% zinc) were dissolved in 139 g of cresol and 102 g of xylene at an internal temperature of 80 ° C. And resin content 50%
Paint was obtained.

Comparative Example 7 In a 1-liter flask equipped with a stirrer and a thermometer, a 50% solution of the polyesterimide resin (2) of Reference Example 2 was prepared.
00g, Epicoat 1007 (manufactured by Yuka Shell) 40
g, Vinilec H (manufactured by Chisso) 40 g, Coronate 2
503 (manufactured by Nippon Polyurethane) 50 g, Desmodur
30 g of CT-Stable (manufactured by Bayer AG) and 2 g of zinc naphthenate (8% zinc) were dissolved in 81 g of cresol and 77 g of xylene at an internal temperature of 80 ° C. to obtain a paint having a resin content of 50%. .

Comparative Example 8 In a 1-liter flask equipped with a stirrer and a thermometer, a 50% solution of the polyesterimide resin (2) of Reference Example 2 was prepared.
00g, Epicoat 1007 (manufactured by Yuka Shell) 40
g, Vinilec H (manufactured by Chisso) 40 g, Coronate 2
503 g (manufactured by Nippon Polyurethane), 432 g of Desmodur CT-table (manufactured by Bayer), and 10 g of zinc naphthenate (8% zinc) in cresol 812.
g and 348 g of xylene at an internal temperature of 80 ° C. to obtain a paint having a resin content of 50%.

Comparative Example 9 In a 1-liter flask equipped with a stirrer and a thermometer, a 50% solution of the polyesterimide resin (3) of Reference Example 3 was prepared.
00g, Epicoat 1007 (manufactured by Yuka Shell) 30
g, Vinilec H (manufactured by Chisso) 30 g, Coronate 2
503 (manufactured by Nippon Polyurethane) 20 g, Desmodur
180 g of CT-Table (manufactured by Bayer) and 4 g of zinc naphthenate (8% zinc) were dissolved in 149 g of cresol and 107 g of xylene at an internal temperature of 80 ° C.
0% paint was obtained.

Comparative Example 10 In a 1-liter flask equipped with a stirrer and a thermometer, a 50% solution of the polyesterimide resin (3) of Reference Example 3 was prepared.
00g, Epicoat 1007 (manufactured by Yuka Shell) 30
g, Vinilec H (manufactured by Chisso) 30 g, Coronate 2
503 (manufactured by Nippon Polyurethane), 10 g of Desmodur CT-table (manufactured by Bayer), and 4 g of zinc naphthenate (8% zinc) are dissolved in 149 g of cresol and 107 g of xylene at an internal temperature of 80 ° C. And resin 5
0% paint was obtained.

Comparative Example 11 In a 1-liter flask equipped with a stirrer and a thermometer, a 50% solution of the polyesterimide resin (4) of Reference Example 4 was prepared.
00g, Epicoat 1007 (manufactured by Yuka Shell) 70
g, Vinilec H (manufactured by Chisso) 30 g, Coronate 2
503 g of 503 (made by Nippon Polyurethane), 100 g of Desmodur CT-table (made by Bayer), and 5 g of zinc naphthenate (8% zinc)
And 135 g of xylene at an internal temperature of 80 ° C. to obtain a paint having a resin content of 50%.

Comparative Example 12 In a 1-liter flask equipped with a stirrer and a thermometer, a 50% solution of the polyesterimide resin (4) of Reference Example 4 was prepared.
00g, Epicoat 1007 (manufactured by Yuka Shell) 30
g, Vinylek H (manufactured by Chisso Corporation) 70 g, Coronate 2
503 g of 503 (made by Nippon Polyurethane), 100 g of Desmodur CT-table (made by Bayer), and 5 g of zinc naphthenate (8% zinc)
And 135 g of xylene at an internal temperature of 80 ° C. to obtain a paint having a resin content of 50%. Tables 2 and 3 show the composition of the coating materials of the above Examples and Comparative Examples.

[0058]

[Table 2]

[0059]

[Table 3]

(Evaluation of Insulating Paint) The insulating paints of the above Examples and Comparative Examples were applied to a copper wire having a conductor diameter of 0.20 mm in a horizontal baking furnace having a furnace length of 2.5 m, a furnace temperature of 400 ° C., and six dies. It was applied and baked under the conditions of a take-up speed of 50 m / min to produce an insulated wire having a film thickness of 0.015 mm.

An insulated wire obtained by using the insulating paints of the above Examples and Comparative Examples, and a polyester insulated wire (insulated paint manufactured by Dainichi Seika Kogyo Co., Ltd.) manufactured at a furnace temperature of 500 ° C. and a take-up speed of 40 m / min for comparison. Using E1050, Comparative Example 1
3), polyester imide insulated wire (using insulation paint EH402 manufactured by Dainichi Seika Kogyo Co., Comparative Example 14), and polyamide imide insulated wire (insulated paint AI60 manufactured by Dainichi Seika Industry Co., Ltd.)
2 Use, Comparative Example 15), the characteristics of the insulated wire were tested by the following methods. The results are shown in Tables 4 to 6.

(Test Method) (1) The test was carried out in accordance with JIS C 3003 (Test method for enameled copper wire and enameled aluminum wire). (2) Stretched pinhole The sample was measured according to the pinhole test of JIS C 3003 immediately after 3% rapid elongation. (3) Dielectric breakdown voltage after thermal deterioration JIS C 3003 two-twisted sample in the dielectric breakdown voltage test was left in a 220 ° C constant temperature bath for 168 hours.
This was performed according to the dielectric breakdown voltage test of No. 3003, and the holding ratio with respect to the initial value was measured. (4) Moisture and heat resistance A two-twisted sample in a breakdown voltage test according to JIS C 3003 was placed in a 700 ml autoclave at 0.2 vol water.
%, Left in a thermostat at a predetermined temperature for 168 hours, and performed according to the dielectric breakdown voltage test of JIS C 3003 to measure the holding ratio with respect to the initial value.

[0063]

[Table 4] Evaluation result (1)

[0064]

[Table 5] Evaluation result (Part 2)

[0065]

[Table 6] Evaluation results (part 3)

The results in Tables 4 to 6 indicate that the insulated wire using the insulating paint of the present invention has excellent heat resistance and moisture heat resistance while overcoming the disadvantages of the comparative example and the insulated wire using the conventional insulating paint. It shows that it has.

[0067]

According to the present invention described above, there is provided an insulating paint which has both excellent heat resistance and wet heat resistance, and can sufficiently respond to the recent requirements for the characteristics of insulated wires used in electric equipment.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09D 179/08 C09D 179/08 D H01B 3/30 H01B 3/30 E

Claims (6)

[Claims] 1. A (A) 100 parts by weight of a polyesterimide resin having a five-membered imide group in the molecule,
(B) 10-60 parts by weight of an epoxy resin, (C) 10-60 parts by weight of a polyvinyl formal resin, and (D) a stabilized isocyanate compound based on 100 parts by weight of all resin components. Is contained in a proportion of 50 to 500 parts by weight. 2. The polyesterimide resin (A) described above.
Is a mixture of a dihydric carboxylic acid containing a 5-membered imide group and an aromatic polycarboxylic acid and a polyhydric alcohol, wherein the total alcohol component / total acid formation (equivalent ratio) is 1.2 to 3.0. The insulating paint according to claim 1, which is obtained by reacting in the range of. 3. The polyhydric alcohol according to claim 2, wherein at least one dihydric alcohol / at least one trihydric or higher polyhydric alcohol (equivalent ratio) is used in a ratio of 0.1 to 2.5. Insulating paint as described. 4. The insulating paint according to claim 2, wherein the proportion of the divalent carboxylic acid containing a 5-membered imide group in the total acid component is at least 10 equivalent%. 5. The insulating paint according to claim 1, wherein the stabilized isocyanate compound is an aromatic polyisocyanate having at least two benzene rings in a molecule and / or a block body thereof. 6. The above-mentioned aromatic polyisocyanate block of diisocyanate having two benzene rings in a molecule (1) / block of diisocyanate having three benzene rings in a molecule (2) (weight) The insulating paint according to claim 4, wherein the ratio (ratio) is used in a ratio of 20/80 to 90/10.