JPH09115348A - Heat-resistant insulated wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat-resistant wire having excellent coating strength by forming a lower layer of specific polysilazane in a heat resistant insulation wire composed of base material, the lower layer coating the base material, and an upper layer coating the lower layer opposite to the base material. SOLUTION: A lower layer is formed of polysilazane having repetition units -SiR<1> R<2> -NH- and -SiR<3> R<4> -Ar-SiR<5> R<6> -NH- [R<1to6> is H, (substitution) alkyl, alkenyl, alkoxy, phenyl, aryl, a group containing C; Ar is a group containing one or more of aromatic rings]. It is desirable that the repetition units of the polysilazane are -SiR<1> R<2> -NH-, -SiR<3> R<4> -Ar-SiR<5> R<6> -NH-, -SiR<7> R<8> -NH-Ar-NH- and -SiR<9> R<10> -Ar-NH-SiR<11> R<12> -NH-Ar-NH-(R<7to12> is R<1> ). It is also desirable that the lower layer contains inorganic powder (for instance silicon dioxide) in addition to the polysilazane.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat resistant insulated wire having heat resistance and excellent mechanical properties.

[0002]

2. Description of the Related Art Insulated wires are sometimes used in equipment such as special chemical plants and heating equipment that require safety even when exposed to high temperatures. Also, the insulated wire is
It is also used in automotive electrical components that are exposed to high temperature environments. Conventionally, organic insulating materials such as polyimide, amide imide, and fluororesins have been used for the insulating film for insulated wires used in such places.
However, in applications requiring higher heat resistance, and in applications requiring higher reliability such as use under high temperature, the organic insulating film as described above is insufficient, and for example, the glass of the film is used. At temperatures above the transition temperature, the film softens and begins to decompose. Therefore, there has been proposed an insulated electric wire coated with an inorganic insulating film containing a silicone resin and preceramics such as polycarbosilane and polytitanosilane which are turned into ceramics by firing.

[0003]

However, although the inorganic insulating film containing the above-mentioned silicone resin and the proposed preceramics has improved heat resistance as compared with the organic insulating film, the film strength is higher than that of the organic insulating film. Is significantly inferior to. Therefore, when the insulated wire coated with the above-mentioned inorganic insulating coating is processed, there is a problem that the coating is cracked or easily scratched, and in the worst case, the insulating coating is peeled off. Insulating film made of polysilazane,
Compared to the other resins mentioned above, the adhesion of the insulated wire to the conductor is better, so cracks are less likely to occur in the coating when processed, and scratches are less likely to occur, but compared to insulated wires with an organic insulation coating Then, it was still insufficient.

[0004]

Means for Solving the Problems Accordingly, the present inventors have:
By studying the structure of polysilazane, the strength of the insulating film has been improved. As a result of earnest research, by introducing a silylbenzene component into the polysilazane structure,
It has been found that the film strength can be improved and the work resistance of the heat resistant insulated wire can be greatly improved. In the present invention, it was also found that by coating the polysilazane film with an organic material, the electric wire workability is dramatically improved. This invention uses polysilazane introduced with a silylbenzene component as a lower layer forming material, and produces a heat-resistant insulated wire coated with an organic film as an upper layer on the side opposite to the base material of the lower layer. It is intended to provide a heat-resistant insulated electric wire capable of achieving both workability.

The present invention is a heat-resistant insulated wire comprising a base material, a lower layer covering the base material, and an upper layer covering the lower layer on the side opposite to the base material, wherein the lower layer is a repeating unit: (a)- SiR ¹ R ² -NH- and (b) -SiR ³ R ⁴ -
⁵ R ⁶ -NH- (wherein ^{Ar-SiR, R 1, R} 2, R 3, R 4,
R ⁵ and R ⁶ are selected from a hydrogen atom, a substituted or unsubstituted alkyl group, an alkenyl group, an alkoxy group, a phenyl group, an aryl group, and a group containing a carbon atom. Ar is a group containing at least one aromatic ring. And a heat resistant insulated wire formed of polysilazane.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, polysilazane has repeating units of (a) -SiR ¹ R ² -NH- and (b) -SiR ³ R ⁴ -Ar-SiR ⁵ R ⁶ -NH- ( In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are hydrogen atoms,
It is selected from substituted or unsubstituted alkyl groups, alkenyl groups, alkoxy groups, phenyl groups, aryl groups, and groups containing carbon atoms. Ar is a group containing at least one aromatic ring. ) Is meant. These polysilazanes can be synthesized by using one or more dichlorosilanes and ammonia.

Here, the dichlorosilane is methyl.
(Hydro) dichlorosilane, ethyl (hydro) dichlorosilane, vinyl (hydro) dichlorosilane, allyl (hydro) dichlorosilane, phenyl (hydro) dichlorosilane, benzyl (hydro) dichlorosilane, dimethyldichlorosilane, methylphenyldichlorosilane, Diphenyldichlorosilane, methylvinyldichlorosilane, divinyldichlorosilane, diethyldichlorosilane, ethylmethyldichlorosilane, ethylphenyldichlorosilane, ethylvinyldichlorosilane, ethoxymethyldichlorosilane, ethoxyethyldichlorosilane, ethoxyphenyldichlorosilane, ethoxyvinyldi Chlorosilane, methyl 3,3,3-trifluoropropyldichlorosilane, allylmethyldichlorosilane, 3-chloropropylmethyldichlorosilane, methyl Pills dichlorosilane, etc. diethoxy dichlorosilane and 3-cyanopropyl methyl dichlorosilane, and the like, 1 selected from these
It may be seed or higher.

[0008] The polysilazane of the present invention, -SiR ³ R ⁴ -
It has a silylbenzene component represented by Ar—SiR ⁵ R ⁶ —NH—. In the present invention, the silylbenzene component introduced into polysilazane is 1,4-bis (dimethylchlorosilyl) benzene, 1,4-bis (methylphenylchlorosilyl) benzene, 1,4-bis (diphenylchlorosilyl) benzene. At least one bis (chlorosilyl) benzene such as 1,4 bis (methylhydrochlorosilyl) benzene and 1,4-bis (phenylhydrochlorosilyl) benzene can be introduced by using it as a raw material.

The polysilazane having the repeating units (a) and (b) can be produced, for example, by mixing dichlorosilane and bis (chlorosilyl) benzene and then performing ammonolysis with ammonia. The molar ratio of dichlorosilane to bis (chlorosilyl) benzene is usually 1: 0.1 to 1: 2, preferably 1: 0.2.
1: 1. The molar ratio of the total of dichlorosilane and bis (chlorosilyl) benzene to ammonia is
Usually, it is 1: 0.8 to 1: 1.5. The reaction temperature of the total of dichlorosilane and bis (chlorosilyl) benzene with ammonia is usually -50 to 50 ° C, and for example, 0
° C. The reaction time is usually 1 to 5 hours.

The number average molecular weight (Mn) of the polysilazane having the repeating units (a) and (b) is usually 500.
It is 10,000. In the polysilazane having the repeating units (a) and (b), the molar ratio of the repeating units (a) and (b) is 1: 0.1 to 1: 1.

Further, the repeating unit is (a) -SiR ¹ R
^{2 -NH -, (b) -SiR} 3 R 4 -Ar-SiR 5 R 6 -NH
^{- (c) -SiR 7 R 8} -NH-Ar-NH- and (d)
^{-SiR 9 R 10 -Ar-SiR 11} R 12 -NH-Ar-NH-
(Wherein, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R
⁹ , R ¹⁰ , R ¹¹ and R ¹² are selected from a hydrogen atom, a substituted or unsubstituted alkyl group, an alkenyl group, an alkoxy group, a phenyl group, an aryl group and a group containing a carbon atom.
Ar is a group containing at least one aromatic ring. It was also found that when polysilazane composed of (1) is used as a material for forming the lower layer, a more remarkable improvement in electric wire workability can be obtained.

Such polysilazanes can be synthesized by using dichlorosilane and bis (chlorosilyl) benzene with ammonia and aromatic diamines. The aromatic diamine as used herein includes p-phenylenediamine, m-phenylenediamine, diaminotoluene, 4,
4'-diaminodiphenyl ether, diaminodiphenyl sulfone, diaminobenzofluorad, diaminoxylene, 4,4'-diaminodiphenylmethane, diaminodiurene, 1,2-bis (anilino) ethane, 2,2-bis (p
-Aminophenyl) propane, 2,2'-bis (p-aminophenyl) hexafluoropropane, 3,3'-dimethyl-4,4'-diaminodiphenyl ether, 3,3'-dimethyl-4,4'-diamino Diphenylmethane and 1,4
Examples include diamines such as -bis (p-aminophenoxy) benzene.

Polysilazanes having repeating units (a) to (d) are dichlorosilane and bis (chlorosilyl).
It can be prepared by mixing benzene, followed by aminolysis with an aromatic diamine, and then ammonolysis with ammonia, or by performing the reaction in the reverse order.
The molar ratio of the sum of dichlorosilane and bis (chlorosilyl) benzene to the sum of ammonia and aromatic diamine is usually 1: 0.8 to 1: 1.5. The reaction temperature for ammonolysis is usually -50 to 50 ° C, for example 0 ° C.
And the reaction temperature for aminolysis is usually -5.
It is 0 to 150 ° C., for example, 100 ° C. The reaction time is
Both are typically 1-5 hours.

The number average molecular weight (Mn) of the polysilazane having repeating units (a) to (d) is usually 500 to 1.
It is 0,000. In polysilazane having repeating units (a) to (d), repeating units (a) to (d)
The preferred molar ratio of the repeating unit is as follows; 40-60 mol% of the repeating unit (a) and 15-2 of the repeating unit (b).
5 mol%, repeating unit (c) 15-25 mol%, and repeating unit (d) 5-15 mol%. The terminal group of polysilazane is, for example, Si-H, Si-Cl, Si-OH,
N-H.

In the present invention, the heat resistance of the film can be improved by mixing the above polysilazane with an inorganic powder to form an insulating film. Here, examples of the inorganic powder include oxide-based ceramics such as silicon oxide, aluminum oxide, magnesium oxide, titanium oxide, zirconium oxide, copper oxide, iron oxide, mica, and zirconium silicate; and silicon nitride, boron nitride, and the like.
Examples thereof include non-oxide ceramics such as aluminum nitride, titanium nitride, silicon carbide, titanium carbide, zirconium carbide, titanium boride, zirconium boride and potassium titanate. When inorganic powder is mixed with polysilazane,
The amount of the inorganic powder relative to polysilazane is 5 to 75% by weight.
Is preferred, and particularly preferably 10 to 50% by weight. As a method for mixing the inorganic powder with the polysilazane, any known mixing method may be used. For example, the mixture can be added to the polysilazane solution and mixed by stirring, or can be mixed with a resolver, a sand mill, a roll, or the like. . The inorganic powders may be used either alone or as a mixture.

The organic material for forming the upper layer of the present invention includes:
For example, polyimide, polyarylate, polyether sulfone, polysulfone, polyetherimide, polyether ether ketone, polyphenylene sulfide, polyoxybenzoyl, aramid, polybenzimidazole,
Examples include polyamide imide, polyester imide, polyurethane, polyester imide, polyester, polyvinyl formal, phenoxy, aromatic polyamide, polyethylene, polypropylene, polybutylene, and fluororesin. Generally, any organic insulating material is applicable. . In addition, it is preferable to use polyimide as the organic material, since it has good electric wire workability and heat resistance.

The base material used in the heat resistant insulated wire of the present invention may be any material other than copper, Ni-plated copper, aluminum, gold, gold-plated copper and the like. For the above base material,
The coating for forming an insulating film of the present invention is prepared by adjusting a coating solution prepared by dissolving an insulating film forming material in a solvent,
This is done by applying it to the substrate. This is the same for both the lower layer and the upper layer. Examples of the coating method for forming the insulating film include known methods such as a dipping method, a die method, and a felt method.

The solvent used for dissolving the insulating film forming material is an aprotic basic solvent, a hydrocarbon-based solvent of aliphatic hydrocarbon, alicyclic hydrocarbon and aromatic hydrocarbon, halogenated hydrocarbon and Ethers such as aliphatic ethers and alicyclic ethers can be used. As such a solvent, for example, DMF, DMAC,
Hydrocarbon solvents such as pyrrolidone, xylene, benzene, toluene, ethylbenzene, pentane, hexane, methylpentane, dimethylbutane, heptane, octane, nonane, decane and dodecane, and methylene chloride, chloroform, carbon tetrachloride, ethylene chloride, trichloroethane and Halogenated hydrocarbons such as tetrachloroethane may be mentioned. The concentration of the coating solution for forming the insulating film is
A range of 10 to 80% by weight is preferable, for example 20% by weight
It is.

In the present invention, in order to coat the heat resistant insulated wire with the lower insulating coating, the above coating is fired by a known method to form a polysilazane coating.
Regarding the firing for forming the lower layer film, the preferable firing temperature is in the range of 300 to 600 ° C., and the preferable firing time is 30 seconds to 120 minutes, for example, 350 ° C. for about 120 minutes. Depending on these insulating film forming conditions, the dry film thickness of the insulating film is usually in the range of 5 to 50 μm, for example, about 12 μm.

In the present invention, the side of the lower layer coating opposite to the substrate is further coated with an upper layer made of an organic material. The upper layer can be formed by applying the above coating to the side of the lower layer opposite to the substrate and baking. A preferable firing temperature is in the range of 200 to 500 ° C., and a preferable firing time is 30 seconds to 120 minutes, for example, 250 ° C. for about 5 minutes. The thickness of the upper layer film formed by this is 2
It is preferably about 30 μm, for example about 6 μm.

[0021]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to the following examples. Synthesis Example 1 After replacing the reaction vessel with dry nitrogen gas, 800 g of distilled and purified dichloromethane was put therein, cooled to 0 ° C. or lower, and then methyldichlorosilane (CH ₃ HSiCl ₂ ) 8
0g and 1,4-bis (dimethylchlorosilyl) benzene 5
0 g was added. After stirring the mixture for 30 minutes, 2 NH ₃ was added.
It was introduced at 00 ml / min for 3 hours for ammonolysis. N
The solution became a white paste due to the precipitation of H ₄ Cl. The reaction mixture was filtered, the filtrate was taken out and dried in vacuum to obtain a highly viscous liquid. Formation of the copolymerized polysilazane was confirmed by the attribution of each peak in the IR spectrum of the highly viscous liquid. When the molecular weight was measured by GPC, the number average molecular weight (Mn) was 1200 and the weight average molecular weight (Mw) was 1500.

Synthesis Example 2 After the reaction vessel was replaced with dry nitrogen gas, 800 g of distilled and purified dichloromethane was put therein, cooled to 0 ° C. or lower, and then methyldichlorosilane (CH ₃ HSiCl ₂ ) 80
g and diphenyldichlorosilane (Ph ₂ SiCl ₂ ) 20 g
And 1,4-bis (dimethylchlorosilyl) benzene 5
0 g was added. After stirring the mixture for 30 minutes, 2 NH ₃ was added.
It was introduced at 00 ml / min for 3.5 hours for ammonolysis. The solution became a white paste due to NH ₄ Cl precipitation. The reaction mixture was filtered, the filtrate was taken out and dried in vacuum to obtain a highly viscous liquid. High viscosity liquid I
The attribution of each peak in the R spectrum confirmed the formation of the copolymerized polysilazane. When the molecular weight was measured by GPC, the number average molecular weight (Mn) was 1200 and the weight average molecular weight (Mw) was 1500.

Synthesis Example 3 After replacing the reaction vessel with dry nitrogen gas, 800 g of distilled and purified dichloromethane was put therein, and then 80 g of methyldichlorosilane (CH ₃ HSiCl ₂ ) and 1,4-bis (dimethylchlorosilyl) benzene. 50 g was added. 21 g of p-phenylenediamine was mixed and dissolved in 120 g of pyridine, and the mixture was charged, heated and stirred at 100 ° C. for 4 hours, and subjected to aminolysis with an aromatic diamine. Then add NH ₃ to 20
It was introduced at 0 ml / min for 2.5 hours for ammonolysis.
The solution became a white paste due to NH ₄ Cl precipitation. The reaction mixture was filtered, the filtrate was taken out and dried in vacuum to obtain a highly viscous liquid. When the molecular weight was measured by GPC, the number average molecular weight (Mn) was 900 and the weight average molecular weight (Mw) was 2200.

Synthesis Example 4 After the reaction vessel was replaced with dry nitrogen gas, 800 g of distilled and purified dichloromethane was put therein, and then 80 g of methyldichlorosilane (CH ₃ HSiCl ₂ ) and 20 g of diphenyldichlorosilane (Ph ₂ SiCl ₂ ) and 50 g of 1,4-bis (dimethylchlorosilyl) benzene was added. After stirring the mixture for 30 minutes, 1 g of p-phenylenediamine was added.
20 g of pyridine was mixed and dissolved and added, heated and stirred at 100 ° C. for 4 hours, and subjected to aminolysis with an aromatic diamine. Then NH ₃ was introduced at 200 ml / min for 2.5 hours for ammonolysis. The solution became a white paste due to NH ₄ Cl precipitation. Filtering the reaction mixture,
The filtrate was taken out and dried in vacuum to obtain a highly viscous liquid. Formation of the copolymerized polysilazane was confirmed by the attribution of each peak in the IR spectrum of the highly viscous liquid.
When the molecular weight was measured by GPC, the number average molecular weight (Mn) was 1200 and the weight average molecular weight (Mw) was 1500.

Synthesis Example 5 After replacing the reaction vessel with dry nitrogen gas, 800 g of distilled and purified dichloromethane was put therein, and then 3.6 g of methyldichlorosilane (CH ₃ HSiCl ₂ ), and diphenyldichlorosilane (Ph ₂ SiCl ₂ ). 104g and 1,4-bis
50 g of (dimethylchlorosilyl) benzene were added. After stirring the mixture for 30 minutes, 21 g of p-phenylenediamine
Is mixed and dissolved in 120 g of pyridine, and then added,
The mixture was heated and stirred at 4 ° C. for 4 hours, and aminolysis was performed with an aromatic diamine. Then NH ₃ was introduced at 200 ml / min for 2.5 hours for ammonolysis. The solution became a white paste due to NH ₄ Cl precipitation. The reaction mixture was filtered, the filtrate was taken out and dried in vacuum to obtain a highly viscous liquid. Formation of the copolymerized polysilazane was confirmed by the attribution of each peak in the IR spectrum of the highly viscous liquid. The number average molecular weight (Mn) was 1200 and the weight average molecular weight (Mw) was 15 as measured by GPC.
00.

COMPARATIVE SYNTHESIS EXAMPLE 1 After replacing the reaction vessel with dry nitrogen gas, 800 g of distilled and purified dichloromethane was put therein, cooled to 0 ° C. or lower, and then methyldichlorosilane (CH ₃ HSiCl ₂ ) 80.
g was added. After stirring the mixture for 30 minutes, NH ₃ was added to 20
It was introduced at 0 ml / min for 3 hours for ammonolysis. NH
_The solution became a white paste due to the precipitation of ₄ Cl.
The reaction mixture was filtered, the filtrate was taken out and dried in vacuum to obtain a highly viscous liquid. Formation of methylhydropolysilazane was confirmed by the assignment of each peak in the IR spectrum of the highly viscous liquid. When the molecular weight was measured by GPC, the number average molecular weight (Mn) was 800 and the weight average molecular weight (Mw) was 1100.

COMPARATIVE SYNTHESIS EXAMPLE 2 After the reaction vessel was replaced with dry nitrogen gas, 800 g of distilled and purified dichloromethane was put therein, cooled to 0 ° C. or lower, and then methyldichlorosilane (CH ₃ HSiCl ₂ ) 80.
g and 20 g of diphenyldichlorosilane (Ph ₂ SiCl ₂ ) were added. After stirring the mixture for 30 minutes, 200 ml of NH ₃ was added.
It was introduced for 3 hours at a flow rate of 1 minute / minute for ammonolysis. NH ₄ Cl
The solution became a white paste. The reaction mixture was filtered, the filtrate was taken out and dried in vacuum to obtain a highly viscous liquid. Formation of the copolymerized polysilazane was confirmed by the attribution of each peak in the IR spectrum of the highly viscous liquid. Moreover, when the molecular weight was measured by GPC, the number average molecular weight (Mn) = 800 and the weight average molecular weight (M
w) = 1200.

Comparative Example 1 The copolymerized polysilazane obtained in Synthesis Example 1 was dissolved in xylene to prepare a coating solution (20% by weight), which was applied to a nickel-plated copper wire having a diameter of 2.4 mm. The coated nickel-plated copper wire was placed in a constant temperature bath and fired at 300 ° C. for 3 minutes to obtain a coated electric wire having a film thickness of 12 μm. Next, in order to evaluate the mechanical properties of the coating, flexibility (JIS
C-3003 Enamel copper wire and enamel aluminum wire test method) and one-way wear (the same JIS C-300
Evaluation of 3 enamel copper wire and enamel aluminum wire test method) showed that flexibility = 1d was good and unidirectional wear was 350g. 4 wires to check heat resistance
Observation of the state of the film after leaving it in an electric furnace at 00 ° C for 6 hours. Only a few cracks were visible.

Example 1 The electric wire prepared in Comparative Example 1 was coated with a polyimide varnish (Pile ML varnish manufactured by DuPont) and 280 ° C.
It was baked for 5 minutes in a constant temperature bath and covered with a 6 μm film. Next, in order to evaluate the mechanical properties of the coating, the flexibility and the one-way wear property were evaluated by the same method as above, and the flexibility was 1d, and the one-way wear property was 540 g. In order to examine the heat resistance, the state of the film after observing the electric wire in an electric furnace at 400 ° C for 6 hours was observed. The upper polyimide film was burned off, but the lower polysilazane film was only slightly cracked. there were.

[0030] The copolymerization polysilazane obtained in Example 2 Synthesis Example 2 was dissolved in xylene to prepare a coating solution (20 wt%) was applied to a nickel-plated copper wire having a diameter of 2.4 mm. The coated nickel-plated copper wire was put into an electric furnace and baked at 300 ° C. for 5 minutes to obtain a coated electric wire having a film thickness of 12 μm. Next, in order to evaluate the mechanical properties of the coating, flexibility (JIS
C-3003) and one-way wearability (the same, JIS
According to C-3003), flexibility = 1d
Good, one-way wear property = 400 g. To examine the heat resistance, the state of the film after the electric wire was left in an electric furnace at 400 ° C. for 6 hours was observed, and only a slight crack was observed. Next, the prepared electric wire was coated with a polyimide varnish (Pile ML varnish manufactured by DuPont), baked at 280 ° C. for 5 minutes in a constant temperature bath, and covered with a film of 6 μm. Next, in order to evaluate the mechanical properties of the coating, the flexibility and the one-way wear property were evaluated by the same method as above, and the flexibility was 1d good and the one-way wear property was 650 g. When the same test as in Example 1 was performed to examine the heat resistance, similar results were obtained.

[0031] The copolymerization polysilazane obtained in Example 3 Synthesis Example 3 was dissolved in xylene to prepare a coating solution (20 wt%) was applied to a nickel-plated copper wire having a diameter of 2.4 mm. The coated nickel-plated copper wire was put in an electric furnace and fired at 300 ° C. for 3 minutes to obtain a covered electric wire having a film thickness of 12 μm. Next, in order to evaluate the mechanical properties of the coating, flexibility (JIS
C-3003) and one-way wear (the same JIS C
-3003), the flexibility = 1d was good, and the one-way wear property was 450 g. In order to investigate the heat resistance, when the electric wire was left in an electric furnace at 400 ° C. for 6 hours, the state of the film was observed, and only slight cracks were found. Next, the prepared electric wire was coated with a polyimide varnish (Pile ML varnish manufactured by DuPont), baked at 280 ° C. for 5 minutes in a constant temperature bath, and covered with a film of 6 μm. Next, in order to evaluate the mechanical properties of the coating, the flexibility and the one-way wear property were evaluated by the same method as above. The flexibility was 1d, and the one-way wear property was 650 g. When the same test as in Example 1 was performed to examine the heat resistance, similar results were obtained.

[0032] The copolymerization polysilazane obtained in Example 4 Synthesis Example 4 was dissolved in xylene to prepare a coating solution (20 wt%) was applied to a nickel-plated copper wire having a diameter of 2.4 mm. The coated nickel-plated copper wire was put into an electric furnace and baked at 300 ° C. for 5 minutes to obtain a coated electric wire having a film thickness of 12 μm. Next, in order to evaluate the mechanical properties of the coating, flexibility (JIS
C-3003) and one-way wear (the same JIS C
-3003), the flexibility = 1d was good, and the one-way wear property was 450 g. To examine the heat resistance, the state of the film after the electric wire was left in an electric furnace at 400 ° C. for 6 hours was observed, and only a slight crack was observed. Next, the prepared electric wire was coated with a polyimide varnish (Pile ML varnish manufactured by DuPont), baked at 280 ° C. for 5 minutes in a constant temperature bath, and covered with a film of 6 μm. Next, in order to evaluate the mechanical properties of the coating, the flexibility and the one-way wear property were evaluated by the same method as above, and the flexibility was 1d and the one-way wear property was 700 g. When the same test as in Example 1 was performed to examine the heat resistance, similar results were obtained.

[0033] was dissolved copolymerized polysilazanes obtained in Example 5 Synthesis Example 5 to pyrrolidone to prepare a coating solution (20 wt%) was applied to a nickel-plated copper wire having a diameter of 2.4 mm. The coated nickel-plated copper wire was put in an electric furnace and fired at 350 ° C. for 5 minutes to obtain a coated electric wire having a film thickness of 12 μm.
Next, in order to evaluate the mechanical properties of the coating, flexibility (JIS
C-3003) and one-way wearability (the same, JIS
According to C-3003), flexibility = 1d
Good, wear resistance in one direction = 550 g. To examine the heat resistance, the state of the film after the electric wire was left in an electric furnace at 400 ° C. for 6 hours was observed, and only a slight crack was observed. Next, the produced electric wire was coated with a polyimide varnish (Pile ML varnish manufactured by DuPont), baked at 280 ° C. for 5 minutes in a constant temperature bath, and coated with 6 μm. Then the flexibility to evaluate the mechanical properties of the coating
(JIS C-3003 enamel test method) and one-way wear
When evaluated according to (JIS C-3003 enamel test method), flexibility = 1d was good and one-way wear was 850g.
When the same test as in Example 1 was conducted to examine the heat resistance,
Similar results were obtained.

Example 6 The copolymerized polysilazane obtained in Synthesis Example 5 was dissolved in pyrrolidone to prepare a coating solution (20% by weight), which was applied to a nickel-plated copper wire having a diameter of 2.4 mm. The coated nickel-plated copper wire is put in an electric furnace and heated at 350 ° C for 12
The coated wire was baked for 0 minutes to obtain a coated electric wire having a thickness of 12 μm. Next, in order to evaluate the mechanical properties of the coating, flexibility (J
One-way wear (according to IS C-3003) (same as JI
Flexibility = 1.
d was good and one-way wear was 550 g. To examine the heat resistance, the state of the film after the electric wire was left in an electric furnace at 400 ° C. for 6 hours was observed, and only a slight crack was observed. Next, a polyamide imide varnish (HI-405 varnish manufactured by Hitachi Chemical Co., Ltd.) is coated on the prepared electric wire, and baked at 250 ° C. for 5 minutes in a constant temperature bath to give 6 μm.
m coated. Next, in order to evaluate the mechanical properties of the film, the flexibility and the one-way wear property were evaluated by the same method as above. Flexibility = 1d good, one-way wear property = 80
It was 0 g. In order to examine the heat resistance, the state of the coating after observing the electric wire in an electric furnace at 400 ° C for 6 hours was observed. The upper polyamideimide coating was discolored due to deterioration, but the lower polysilazane coating was slightly cracked. It was only seen.

Comparative Example 2 The methylhydropolysilazane obtained in Comparative Synthesis Example 1 was dissolved in xylene to prepare a coating solution (20% by weight).
Was prepared and applied to a nickel-plated copper wire having a diameter of 2.4 mm. Put the coated nickel-plated copper wire in a constant temperature bath,
The coated wire was baked in air at 250 ° C. for 3 minutes to obtain a coated electric wire having a thickness of 12 μm. Next, in order to evaluate the mechanical properties of the coating, flexibility (according to JIS C-3003) and rubbing resistance (unidirectional wear resistance) [of the coating when a core wire and a piano wire of the same diameter were rubbed together] The withstand load (g)] was evaluated to be flexibility = 1d and unidirectional abrasion resistance = 100g. The characteristic stability of the coating when left in the air was the same as in Example 2. 400 wires to check heat resistance
When the state of the coating film after observing for 6 hours in an electric furnace at ℃ was observed, there was a portion where the coating film fell off.

Comparative Example 3 The copolymerized polysilazane obtained in Comparative Synthesis Example 2 was dissolved in xylene to prepare a coating solution (20% by weight), which was applied to a nickel-plated copper wire having a diameter of 2.4 mm.
The coated nickel-plated copper wire was placed in a constant temperature bath and baked in air at 250 ° C. for 5 minutes to obtain a coated electric wire having a film with a thickness of 12 μm. Next, in order to evaluate the mechanical properties of the coating, flexibility (according to JIS C-3003) and rubbing resistance (unidirectional wear resistance) [of the coating when a core wire and a piano wire of the same diameter were rubbed together] The withstand load (g)] was evaluated to be flexibility = 1d and unidirectional wear resistance = 150 g.
The characteristic stability of the coating when left in the air was the same as in Example 2. In order to examine the heat resistance, the state of the film after observing the electric wire for 6 hours in an electric furnace at 400 ° C. was observed, and there was a part where the film fell off.

Example 7 The copolymerized polysilazane obtained in Synthesis Example 1 was dissolved in xylene, and alumina was added to the copolymerized polysilazane at 25%.
A total thickness of 18 μm was obtained in the same manner as in Example 1 except that the coating solution was prepared by mixing so as to have a weight percentage.
A coated electric wire having a film of m was obtained. The obtained coated electric wire had flexibility of 1d and good wear resistance of 500 g, but in the heat resistance test, no crack was found in the lower polysilazane film.

[0038]

INDUSTRIAL APPLICABILITY In a heat-resistant insulated wire comprising a base material, a lower layer coating the base material, and an organic material coating the lower layer on the side opposite to the base material, polysilazane containing a silylbenzene component is used as a lower layer forming material By producing a heat-resistant insulated wire having an upper layer coated with an organic film on the side opposite to the base material of the lower layer, both heat resistance and wire workability can be achieved. Furthermore, the insulated electric wire coated with this insulating film can also improve the mechanical properties of the insulating film such as flexibility and one-way wear resistance.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical indication location H01B 3/46 H01B 3/46 H (72) Inventor Narihiko Inayoshi 1-chome, Showa-cho, Kariya city, Aichi prefecture Address: Nippon Denso Co., Ltd.

Claims (4)

[Claims] 1. A heat-resistant insulated wire comprising a substrate, a lower layer covering the substrate, and an upper layer covering the lower layer on the side opposite to the substrate, wherein the lower layer has a repeating unit: (a) -SiR ^1. R ² -NH- and (b) -SiR ³ R ⁴ -
⁵ R ⁶ -NH- (wherein ^{Ar-SiR, R 1, R} 2, R 3, R 4,
R ⁵ and R ⁶ are selected from a hydrogen atom, a substituted or unsubstituted alkyl group, an alkenyl group, an alkoxy group, a phenyl group, an aryl group, and a group containing a carbon atom. Ar is a group containing at least one aromatic ring. ), A heat resistant insulated wire formed of polysilazane. 2. The repeating unit of polysilazane is (a).
^{-SiR 1 R 2 -NH -, (} b) -SiR 3 R 4 -Ar-SiR
^{5 R 6 -NH- (c) -SiR} 7 R 8 -NH-Ar-NH- and ^{(d) -SiR 9 R 10 -Ar} -SiR 11 R 12 -NH-A
r-NH- (in the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ ,
R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ and R ¹² are hydrogen atoms,
It is selected from substituted or unsubstituted alkyl groups, alkenyl groups, alkoxy groups, phenyl groups, aryl groups, and groups containing carbon atoms. Ar is a group containing at least one aromatic ring. ) Is a heat-resistant insulated wire according to claim 1. 3. The heat resistant insulated wire according to claim 1, wherein the lower layer contains an inorganic powder in addition to polysilazane. 4. The heat resistant insulated electric wire according to claim 1, wherein the upper organic material is polyimide.