JP5879661B2 - Insulation coating and method for manufacturing the same - Google Patents

Description

  The present invention relates to an insulating covering suitable for use under conditions where the applied voltage is high, and a method for manufacturing the same.

  An insulation covering such as an insulated wire covered with an electric insulation layer is used for conductor parts and coils incorporated in various electric devices. And in electric equipments, such as a motor used on the conditions with a high applied voltage, a high voltage is applied to an insulated wire and it becomes easy to generate | occur | produce partial discharge (corona discharge) on the surface of an insulation coating layer. When corona discharge occurs, the temperature rises locally, ozone or ions are generated, the insulating coating layer is eroded and dielectric breakdown occurs, and the life of the electrical device is shortened. Therefore, an insulating coating layer having a high applied voltage is required to increase the starting voltage of partial discharge (corona discharge).

  In addition, the insulation coating layer with high applied voltage has high heat resistance and high flame resistance in the event of a fire (does not generate harmful gases even if burned, or suppresses the generation of harmful gases to a small amount. It is also important to have heat and humidity resistance as environmental resistance.

  On the other hand, considering the case of processing an insulation covering for incorporation into an electrical device, for example, in the case of an insulated wire for a coil, the coil winding process has been speeded up and streamlined. Instead, processing by an automatic coil winding machine has become mainstream. The same applies to insulation coverings other than the insulated wire for coils, and for example, it has become mainstream to automate pressing and the like using a robot or the like. However, when such automatic processing is performed, since a large tension is applied to the insulating coating body, the insulating coating layer is easily stressed and easily damaged. On the other hand, the process of incorporating a processed insulation coating into various electrical devices has become more prevalent because the automatic loading process using a machine such as a robot has become the mainstream instead of the conventional manual work. It has become like this. Under such an environment, the insulating coating bodies or between the insulating coating bodies and their contact objects are easily rubbed, and insulation failure due to scratching (scratching) of the insulating coating layer is likely to occur. Therefore, an insulating coating layer having high scratch resistance is required.

  On the other hand, for example, as a method of increasing the starting voltage value of partial discharge, a method of forming an insulating coating layer with a low dielectric constant material is known. As a low dielectric constant insulating material, polyimide, fluororesin Aromatic polysulfones are known. In Patent Document 1, a resin composition containing a mixed resin of polyesterimide and polyethersulfone is applied and baked to form an insulating coating layer having a high partial discharge start voltage and excellent mechanical strength and heat resistance. Is disclosed. Patent Document 2 discloses an insulating coating layer using a mixed resin of a resin selected from polyamide, polyimide, polyesterimide and H-type polyester and a low dielectric constant resin selected from fluororesin and polysulfone. Yes.

  However, a certain thickness is required for the insulating coating layer having a high applied voltage. However, when an insulating coating layer is formed by a process consisting of casting and baking using an insulating composition for forming the insulating coating layer. These processes need to be repeated many times, making it difficult to do industrially. Therefore, it is preferable to form the insulating coating layer by melt extrusion or pressing using an insulating composition containing a thermoplastic resin.

  As described above, the insulating coating layer having a high applied voltage is required to be manufactured using a thermoplastic resin, to have a high partial discharge starting voltage, and to have heat resistance, flame resistance, environmental resistance, and scratch resistance. It is done. Examples of materials that can form such an insulating layer include polysulfone and fluororesin.

JP 2009-277369 A JP 2010-67521 A

However, polysulfone is too rigid and poor in chemical resistance, and the insulating coating layer formed using it is prone to cracking when it comes into contact with chemicals such as polar organic solvents under stress deformation (stress resistance) There was a problem that the cracking property was low. For example, in the case of an insulated wire, a coil is produced by winding the insulated wire, and when the varnish is cured after being immersed in a varnish containing an epoxy resin or the like, a crack is likely to occur in the insulating coating layer.
Further, since the fluororesin has low mechanical strength, there is a problem that it is not suitable for forming an insulating coating layer.

  The present invention has been made in view of the above circumstances, can be produced using a thermoplastic resin, has a high partial discharge start voltage, heat resistance, flame resistance, environmental resistance, scratch resistance and chemical resistance. It is an object of the present invention to provide an insulating coating body including an insulating coating layer having the above and a manufacturing method thereof.

To solve the above problem,
The present invention is an insulating coating obtained by coating an object to be coated with an insulating coating layer obtained by using an aromatic polysulfone composition containing an aromatic polysulfone (A) and a fluororesin (B), In the aromatic polysulfone composition, the total content of phenolic hydroxyl groups and salts of phenolic hydroxyl groups present at the ends of the chain structure of the aromatic polysulfone (A) is 1 g of the fluororesin (B). Provided is an insulating covering characterized in that it is 3.0 × 10 ^{−5 to} 10.0 × 10 ⁻⁵ mol.

In the insulation coating body of this invention, it is preferable that the flow start temperature of the said fluororesin (B) is 350 degrees C or less.
In the insulating coating of the present invention, in the aromatic polysulfone composition, the total content of phenolic hydroxyl groups and phenolic hydroxyl group salts present at the ends of the chain structure of the aromatic polysulfone (A) is: it is preferable that the fluorine resin ^{(B) 4.0 × 10 -5 ~9.0} × 10 -5 mol per 1g.
In the insulation coating body of this invention, it is preferable that the said aromatic polysulfone (A) has a repeating unit represented by following General formula (1).
(1) -Ph ¹ -SO ₂ -Ph ² -O-
(In the formula, Ph ¹ and Ph ² are each independently a phenylene group, and one or more hydrogen atoms of the phenylene group may be each independently substituted with an alkyl group, an aryl group, or a halogen atom.)

The present invention also provides an aromatic polysulfone (A2) having a phenolic hydroxyl group and / or a salt of a phenolic hydroxyl group at the end of the chain structure, and an aromatic polysulfone (A1) not corresponding to the aromatic polysulfone (A2). ) And a fluororesin (B) to prepare an aromatic polysulfone composition, and manufacture of an insulating coating that covers an object to be coated with an insulating coating layer formed using the aromatic polysulfone composition In the aromatic polysulfone composition, the amount of the aromatic polysulfone (A1) is 100 parts by mass, the amount of the fluororesin (B) is 5-45 parts by mass, and the aromatic polysulfone composition The total content of the phenolic hydroxyl group and the salt of the phenolic hydroxyl group present at the end of the chain structure To provide a manufacturing method of the insulating cover member, characterized in that the relative fluororesin (B) 1 g and 3.0 × ^{10 -5} ~10.0 × ¹⁰ -5 mol.

  According to the present invention, an insulation having an insulating coating layer that can be produced using a thermoplastic resin, has a high partial discharge start voltage, and has heat resistance, flame resistance, environmental resistance, scratch resistance, and chemical resistance. A covering and a manufacturing method thereof are provided.

The insulating coating according to the present invention is an insulating coating obtained by coating an object to be coated with an insulating coating layer obtained by using an aromatic polysulfone composition containing an aromatic polysulfone (A) and a fluororesin (B). In the aromatic polysulfone composition, the phenolic hydroxyl group present at the end of the chain structure of the aromatic polysulfone (A) and a salt of the phenolic hydroxyl group (hereinafter these are collectively referred to as “terminal phenolic”). The total content of “hydroxyl groups”) is 3.0 × 10 ^{−5 to} 10.0 × 10 ⁻⁵ mol with respect to 1 g of the fluororesin (B).
The said insulation coating layer shows the outstanding chemical resistance by forming from the thing using the said aromatic polysulfone (A) and a fluororesin (B). Here, “chemical resistance” means that the insulation coating layer is in a state where stress is applied even when residual stress is generated, and cracks are generated even if it comes into contact with a chemical such as a polar organic solvent. It means that it is suppressed (high stress crack resistance). Moreover, since the said insulation coating layer uses aromatic polysulfone (A), in addition to thermoplasticity, it has sufficient heat resistance, a flame retardance, environmental resistance (humidity resistance), and insulation, The partial discharge starting voltage is high. Furthermore, since the fluororesin (B) is used, it has excellent scratch resistance and flexibility. Therefore, the insulating covering according to the present invention is suitable for application to insulating covering conductors such as coils incorporated in various electric devices used under conditions where the applied voltage is high, and further, the insulating covering layer is scratch resistant. Because of its excellent properties, it is particularly suitable for manufacturing and assembling an insulation-coated conductor and various electric devices incorporating the same by an automatic process.

The aromatic polysulfone (A) typically includes a divalent aromatic group (residue obtained by removing two hydrogen atoms bonded to the aromatic ring from an aromatic compound) and a sulfonyl group (-SO _2- ) and a resin having a repeating unit containing an oxygen atom.

  Moreover, aromatic polysulfone (A) has said terminal phenolic hydroxyl group. By using such an aromatic polysulfone (A), the affinity between the fluororesin (B) described later and the aromatic polysulfone (A) is improved. As a result, the fluororesin (B) is converted into an aromatic polysulfone (A). ), The dispersibility of the aromatic polysulfone composition is improved in a uniform and stable manner, and the insulating coating layer obtained from the aromatic polysulfone composition has excellent scratch resistance and flexibility. It becomes.

  The salt of the phenolic hydroxyl group is composed of an oxyanion group in which protons are dissociated from a hydroxyl group and a counter cation. Examples of the counter cation include alkali ions such as lithium ion, sodium ion, and potassium ion Metal ions; Alkaline earth metal ions such as magnesium ions and calcium ions; Ammonium ions or quaternary ammonium ions obtained by protonating ammonia or primary to tertiary amines. When the counter cation is a polyvalent cation such as an alkaline earth metal ion, the counter anion may include a plurality of oxyanion groups, or the oxyanion group, chloride ion, water Other anions such as oxide ions may be included.

  The aromatic polysulfone (A) has the following general formula (1) because the insulating coating layer described later is particularly excellent in heat resistance, flame retardancy, and chemical resistance, has high mechanical strength, and suppresses gas generation. ) (Hereinafter sometimes referred to as “repeating unit (1)”), and further represented by the following general formula (2) (hereinafter referred to as “repeating unit ( 2) ") and one or more other repeating units such as a repeating unit represented by the following general formula (3) (hereinafter also referred to as" repeating unit (3) "). You may do it.

(1) -Ph ¹ -SO ₂ -Ph ² -O-
(In the formula, Ph ¹ and Ph ² are each independently a phenylene group, and one or more hydrogen atoms of the phenylene group are each independently an alkyl group, an aryl group, a halogen atom, a sulfo group, a nitro group, or an amino group. , May be substituted with a carboxyl group, a hydroxyl group or a salt of a hydroxyl group.)

^{(2) -Ph 3 -R-Ph} 4 -O-
(In the formula, Ph ³ and Ph ⁴ are each independently a phenylene group, and one or more hydrogen atoms of the phenylene group are each independently an alkyl group, an aryl group, a halogen atom, a sulfo group, a nitro group, or an amino group. , A carboxyl group, a hydroxyl group or a salt of a hydroxyl group, R is an alkylidene group, an alkylene group, an oxygen atom or a sulfur atom.)

_{^{(3) - (Ph 5)}} n -O-
(In the formula, Ph ⁵ is a phenylene group, and one or more hydrogen atoms of the phenylene group are each independently an alkyl group, aryl group, halogen atom, sulfo group, nitro group, amino group, carboxyl group, hydroxyl group. Or n may be an integer of 1 to 5, and when n is 2 or more, a plurality of Ph ⁵ may be the same or different from each other.

The phenylene group represented by any of Ph ^{1 to} Ph ⁵ may be a p-phenylene group, an m-phenylene group, or an o-phenylene group. -A phenylene group is preferred.
Examples of the alkyl group which may substitute the hydrogen atom of the phenylene group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group. Group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, 2-ethylhexyl group, n-nonyl group and n-decyl group, and the carbon number thereof is 1-10. It is preferable.
Examples of the aryl group which may substitute the hydrogen atom of the phenylene group include phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, 1-naphthyl group and 2-naphthyl group. The carbon number is preferably 6-20.
Examples of the halogen atom that may substitute the hydrogen atom of the phenylene group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Examples of the hydroxyl group salt that may be substituted with a hydrogen atom of the phenylene group include the same “salt of phenolic hydroxyl group” in terminal phenolic hydroxyl groups.
When the hydrogen atoms of the phenylene group are substituted with these groups, the number thereof is preferably preferably 2 or less, more preferably 1 for each phenylene group, and preferably 2. These substituents may be the same as or different from each other.
Substituent of the hydrogen atom of Ph ¹ ~Ph ⁵ is an alkyl group is preferably an aryl group or a halogen atom.

Examples of the alkylidene group that is R include a methylene group, an ethylidene group, an isopropylidene group, and a 1-butylidene group, and the carbon number thereof is preferably 1-5.
Examples of the alkylene group which is R include a group formed by removing one hydrogen atom from an alkyl group which may substitute a hydrogen atom of the phenylene group, and the carbon number thereof is preferably 1 ~ 5.

  The aromatic polysulfone (A) is obtained by dividing the total amount of all repeating units constituting the aromatic polysulfone (A) by dividing the mass of each repeating unit constituting the aromatic polysulfone (A) by the formula weight of each repeating unit. It is preferable to have 50% by mole or more of repeating unit (1), more preferably 80% by mole or more based on the total amount (mole) of the substance amount (mole), and substantially as a repeating unit. It is more preferable to have only the repeating unit (1). In addition, aromatic polysulfone (A) may have 2 or more types of repeating units (1)-(3) each independently.

The aromatic polysulfone (A) can be produced by polycondensation reaction between a dihalogenosulfone compound corresponding to the repeating unit constituting the aromatic polysulfone (A) and a dihydroxy compound.
For example, the aromatic polysulfone (A) having the repeating unit (1) is a compound represented by the following general formula (4) as the dihalogenosulfone compound (hereinafter sometimes referred to as “compound (4)”). And a compound represented by the following general formula (5) (hereinafter sometimes referred to as “compound (5)”) as the dihydroxy compound.
The aromatic polysulfone (A) having the repeating unit (1) and the repeating unit (2) is represented by the following general formula (6) using the compound (4) as the dihalogenosulfone compound and the dihydroxy compound. Can be produced by using a compound (hereinafter sometimes referred to as “compound (6)”).
The aromatic polysulfone (A) having the repeating unit (1) and the repeating unit (3) is represented by the following general formula (7) as the dihydroxy compound using the compound (4) as the dihalogenosulfone compound. Can be produced by using a compound (hereinafter sometimes referred to as “compound (7)”).

_{^{(4) X 1 -Ph 1 -SO}} 2 -Ph 2 -X 2
(In the formula, X ¹ and X ² are each independently a halogen atom. Ph ¹ and Ph ² are as defined above.)

(5) HO—Ph ¹ —SO ₂ —Ph ² —OH
(In the formula, Ph ¹ and Ph ² are as defined above.)

^{(6) HO-Ph 3 -R} -Ph 4 -OH
(In the formula, Ph ³ , Ph ⁴ and R are as defined above.)

(7) HO— (Ph ⁵ ) _n —OH
(Wherein Ph ⁵ and n are as defined above.)

In the compound (4), X ¹ and X ² are each independently a halogen atom, and examples thereof include the same halogen atoms as may be substituted for the hydrogen atom of the phenylene group.

  In the present invention, the dihalogenosulfone compound and the dihydroxy compound may be used alone or in combination of two or more according to the type of the desired aromatic polysulfone (A). May be.

The polycondensation reaction is preferably performed using a basic compound in a solvent (hereinafter referred to as “polymerization solvent”). The basic compound is preferably an alkali metal carbonate. The alkali metal salt of carbonic acid may be an alkali carbonate that is a normal salt, an alkali bicarbonate that is an acidic salt (alkali hydrogencarbonate), or a mixture of a normal salt and an acidic salt. Good.
As the alkali carbonate, sodium carbonate and potassium carbonate are preferable, and as the alkali bicarbonate, sodium bicarbonate and potassium bicarbonate are preferable.
In this invention, a basic compound may be used individually by 1 type, and may use 2 or more types together.

The polymerization solvent is preferably an organic polar solvent because the raw material monomer (dihalogenosulfone compound, dihydroxy compound) and aromatic polysulfone are highly soluble and the reaction temperature can be set high due to its high boiling point. An aprotic solvent is more preferable because it has a small solvation effect during the nuclear reaction. Examples thereof include sulfoxides such as dimethyl sulfoxide; amides such as 1-methyl-2-pyrrolidone; sulfolane (1,1 -Sulfone such as dimethylsulfone, diethylsulfone, diisopropylsulfone, diphenylsulfone; 1,3-dimethyl-2-imidazolidinone, 1,3-diethyl-2-imidazolidinone, etc. Compounds having a urea skeleton in which hydrogen atoms may be substituted. I can get lost.
In this invention, a polymerization solvent may be used individually by 1 type, and may use 2 or more types together.

  The polycondensation reaction is a dehydrohalogenated polycondensation reaction between a dihalogenosulfone compound and a dihydroxy compound. If no side reaction occurs, the molar ratio of the dihalogenosulfone compound to the dihydroxy compound is close to 1: 1. The higher the amount of the basic compound used, the higher the polycondensation reaction temperature, and the longer the polycondensation reaction time, the higher the degree of polymerization and the reduced viscosity of the resulting aromatic polysulfone (A). It tends to be expensive. However, in practice, for example, when alkali metal salt is used as the basic compound, side reaction such as substitution reaction or depolymerization of halogeno group to hydroxyl group occurs due to alkali hydroxide generated as a by-product. Thus, the resulting aromatic polysulfone (A) has a low degree of polymerization, a reduced reduced viscosity, and has terminal phenolic hydroxyl groups. Therefore, considering the degree of this side reaction, In order to obtain an aromatic polysulfone (A) having a predetermined reduced viscosity and a predetermined amount of terminal phenolic hydroxyl groups, the molar ratio of the dihalogenosulfone compound and the dihydroxy compound, the amount of basic compound used, It is preferable to adjust the reaction temperature and the polycondensation reaction time.

Examples of the dihalogenosulfone compounds include dihalogenobenzenoid compounds, and specific examples thereof include 4,4′-dichlorodiphenylsulfone, 4-chlorophenyl-3 ′, 4′-dichlorophenylsulfone, 4,4. And '-bis (4-chlorophenylsulfonyl) diphenyl.
As the dihalogenosulfone compound, a compound in which a halogen atom has a sulfonyl group bonded to the para position thereof is preferable.

  Examples of the dihydroxy compound include a divalent phenol compound (a divalent compound having a phenol skeleton), and specific examples thereof include 4,4′-dihydroxydiphenylsulfone, bis (4-hydroxy-3,5). -Dimethylphenyl) sulfone, 4,4'-sulfonyl-2,2'-diphenylbisphenol, hydroquinone, resorcin, catechol, phenylhydroquinone, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4 -Hydroxyphenyl) hexafluoropropane, 4,4'-dihydroxydiphenyl, 2,2'-dihydroxydiphenyl, 3,5,3 ', 5'-tetramethyl-4,4'-dihydroxydiphenyl, 2,2'- Diphenyl-4,4′-bisphenol, 4,4 ′ ″-dihydroxy-p Kuo terphenyl, 4,4'-dihydroxydiphenyl sulfide, bis (4-hydroxy-3-methylphenyl) sulfide, and 4,4'-oxy diphenol.

  The dihalogenosulfone compound and the dihydroxy compound are compounds having a phenolic hydroxyl group and a halogen atom, such as 4-hydroxy-4 ′-(4-chlorophenylsulfonyl) biphenyl, instead of part or all of them. It may be used.

  The amount of dihalogenosulfone compound used is preferably 80 to 105 mol% with respect to the dihydroxy compound in order to form terminal phenolic hydroxyl groups, and a higher molecular weight aromatic polysulfone (A) is obtained. From the point which is obtained, it is more preferable that it is 98-105 mol%.

  For example, when the basic compound is an alkali metal carbonate, the amount of the basic compound used is to increase the molecular weight of the aromatic polysulfone (A) and to form the necessary amount of terminal phenolic hydroxyl groups. In addition, the alkali metal is preferably 0.95 mol times or more with respect to the phenolic hydroxyl group of the dihydroxy compound. For example, the amount of the dihalogenosulfone compound used is 80 to 98 mol% based on the dihydroxy compound. In some cases, the alkali metal is preferably 0.95 to 1.005 mol times with respect to the phenolic hydroxyl group of the dihydroxy compound, and the amount of the dihalogenosulfone compound used is 98 to 98% with respect to the dihydroxy compound. In the case of 105 mol%, the phenolic hydroxyl group of the dihydroxy compound And, as an alkali metal, it is preferably from 1.005 to 1.40 mol times. When the basic compound is other than the alkali metal salt of carbonic acid, the amount used may be appropriately adjusted with reference to the amount used. If the amount of the basic compound used is too large, the bond of the produced aromatic polysulfone (A) is likely to be cleaved or decomposed, and the molecular weight tends to be lowered. If the amount is too small, the polycondensation reaction does not proceed sufficiently, and the low molecular weight Only the aromatic polysulfone (A) is obtained, or the amount of terminal phenolic hydroxyl groups is reduced.

  In a typical method for producing an aromatic polysulfone (A) (hereinafter sometimes referred to as “Production Method 1”), as a first step, a dihalogenosulfone compound and a dihydroxy compound are dissolved in a polymerization solvent, As the second stage, a basic compound is added to the solution obtained in the first stage to cause a polycondensation reaction between the dihalogenosulfone compound and the dihydroxy compound, and as the third stage, from the reaction mixture obtained in the second stage. Then, the unreacted basic compound, the by-product (an alkali halide when an alkali metal salt is used as the basic compound), and the polymerization solvent are removed to obtain the aromatic polysulfone (A).

  The melting temperature in the first stage is preferably 40 to 180 ° C. The reaction temperature for the second stage polycondensation is preferably 180 to 400 ° C. If no side reaction occurs, the higher the reaction temperature, the faster the target polycondensation reaction proceeds. Therefore, the resulting aromatic polysulfone (A) has a higher degree of polymerization, resulting in a higher reduced viscosity. Tend to be. However, in fact, the higher the reaction temperature, the easier the side reaction similar to the above occurs, and this side reaction reduces the degree of polymerization of the aromatic polysulfone (A) obtained. On the other hand, when the reaction temperature is too low, the polycondensation reaction hardly proceeds. Therefore, in consideration of the degree of side reaction, it is preferable to adjust the reaction temperature so as to obtain an aromatic polysulfone (A) having a predetermined reduced viscosity and a predetermined amount of terminal phenolic hydroxyl groups.

  In the second stage polycondensation reaction, the temperature is gradually raised while removing by-product water, and after the temperature reaches the reflux temperature of the polymerization solvent, preferably 1 to 50 hours, more preferably 10 to 30 hours, Further, it may be performed by keeping warm. If no side reaction occurs, the longer the polycondensation reaction time, the more the target polycondensation reaction proceeds. Therefore, the resulting aromatic polysulfone (A) has a higher degree of polymerization, resulting in a reduced viscosity. It tends to be higher. However, in practice, the longer the reaction time, the more the same side reaction as described above proceeds, and this side reaction reduces the degree of polymerization of the aromatic polysulfone (A) obtained. On the other hand, when the reaction time is too short, the polycondensation reaction does not proceed sufficiently. Therefore, in consideration of the degree of side reaction, it is preferable to adjust the reaction time so that the aromatic polysulfone (A) having a predetermined reduced viscosity and a predetermined amount of terminal phenolic hydroxyl groups can be obtained.

  In the third stage, first, the aromatic polysulfone (A) is polymerized by removing the unreacted basic compound and the by-product from the reaction mixture obtained in the second stage by filtration or centrifugation. A solution obtained by dissolving in a solvent is obtained. Subsequently, aromatic polysulfone (A) is obtained by removing a polymerization solvent from this solution. The removal of the polymerization solvent may be performed, for example, by directly distilling off the polymerization solvent from the solution, or the solution is mixed with a poor solvent for the aromatic polysulfone (A), and the aromatic polysulfone (A) is removed. You may carry out by depositing and isolate | separating aromatic polysulfone (A) by filtration, centrifugation, etc.

  Examples of the poor solvent for the aromatic polysulfone (A) include methanol, ethanol, isopropyl alcohol, hexane, heptane and water, and methanol is preferable because it is easy to remove.

  When a relatively high melting point polymerization solvent is used, the reaction mixture obtained in the second stage is cooled and solidified, then pulverized, and water is used to remove the powder from the obtained powder. By extracting and removing the basic compound of the reaction and the by-product, the polymerization solvent is extracted and removed using an extraction solvent having a low solubility of the aromatic polysulfone (A) and a high solubility of the polymerization solvent. Aromatic polysulfone (A) may be obtained.

  The powder obtained by cooling and solidifying and pulverizing the reaction mixture preferably has a center particle size of 50 to 2000 μm, more preferably 100 to 1500 μm, and even more preferably 200 from the viewpoint of extraction efficiency and workability during extraction. ˜1000 μm. If the center particle size is too large, the extraction efficiency is poor, and if it is too small, it may solidify during extraction, or clogging may occur during filtration after extraction or during drying. Here, the “center particle diameter” refers to the median diameter D50, which is a numerical value that is equal to each other when the particle diameter is bipolarized.

  Examples of the extraction solvent for extracting and removing the polymerization solvent include a mixed solvent of acetone and methanol when the polymerization solvent is diphenyl sulfone. Here, the mixing ratio of acetone and methanol can usually be determined from the extraction efficiency and the sticking property of the aromatic polysulfone (A) powder.

In another typical method for producing aromatic polysulfone (A) (hereinafter sometimes referred to as “Production Method 2”), as a first step, a dihydroxy compound and a basic compound are reacted in a polymerization solvent. The water produced as a by-product is removed, and as the second stage, a dihalogenosulfone compound is added to the reaction mixture obtained in the first stage, and a polycondensation reaction is carried out. Similarly, from the reaction mixture obtained in the second stage, unreacted basic compound, by-product (an alkali halide when an alkali metal salt is used as the basic compound), and the polymerization solvent are removed. Thus, aromatic polysulfone (A) is obtained.
However, production method 2 is preferably applied when the amount of the dihalogenosulfone compound used is 80 to 98 mol% with respect to the dihydroxy compound. When the usage-amount of a dihalogeno sulfone compound is 98-105 mol% with respect to a dihydroxy compound, when the manufacturing method 2 is applied, the quantity of terminal phenolic hydroxyl groups will decrease.

  In the production method 2, azeotropic dehydration may be performed by adding an organic solvent azeotropic with water in order to facilitate removal of by-product water in the first stage. Examples of organic solvents that azeotrope with water include benzene, chlorobenzene, toluene, methyl isobutyl ketone, hexane, and cyclohexane. The temperature of azeotropic dehydration is preferably 70 to 200 ° C.

  In production method 2, the reaction temperature of the second stage polycondensation is preferably 180 to 400 ° C., and in the same manner as in production method 1, considering the degree of side reaction, a predetermined reduced viscosity and a predetermined amount. It is preferable to adjust the reaction temperature and reaction time of the polycondensation so that an aromatic polysulfone (A) having a terminal phenolic hydroxyl group is obtained.

  The reduced viscosity of the aromatic polysulfone (A) is preferably 0.25 to 0.60 dl / g. By being more than a lower limit, the mechanical strength and chemical resistance of an insulation coating layer will improve, and the amount of gas generation will be controlled. Moreover, by being below the upper limit, the aromatic polysulfone (A) has a sufficient amount of terminal phenolic hydroxyl groups more stably, the melt viscosity does not increase excessively, and the aromatic polysulfone composition is While having an appropriate fluidity | liquidity, a physical property is stabilized and the physical property of an insulating coating layer is stabilized more. And since these effects can be obtained with a good balance, the reduced viscosity of the aromatic polysulfone (A) is more preferably 0.30 to 0.55 dl / g, and still more preferably 0.36 to 0.55 dl. / G.

The content of the terminal phenolic hydroxyl groups of the aromatic polysulfone (A) can be measured, for example, by potentiometric titration. And the detection limit value of the content of the terminal phenolic hydroxyl groups of the aromatic polysulfone (A) is about 4 × 10 ⁻⁷ mol / g. Here, the aromatic polysulfone (A) in which the content of the terminal phenolic hydroxyl groups is less than the detection limit value can ignore the influence of the terminal phenolic hydroxyl groups in the present invention. It can be handled in the same manner as the aromatic polysulfone (A) having no groups.

  Aromatic polysulfone (A) may be used individually by 1 type, and may use 2 or more types together. For example, one type or two or more types of aromatic polysulfone (A) (hereinafter sometimes referred to as “aromatic polysulfone (A2)”) in which the content of terminal phenolic hydroxyl groups is not less than the detection limit value are used. The aromatic polysulfone (A) as a whole can be adjusted so that the terminal phenolic hydroxyl groups are required. In addition, aromatic polysulfone (A) having no terminal phenolic hydroxyl groups or having a content of terminal phenolic hydroxyl groups below the detection limit (hereinafter, referred to as “aromatic polysulfone (A1)” may be used. .)) And one or more of aromatic polysulfone (A2) are used in combination, and the total amount of terminal phenolic hydroxyl groups is required for aromatic polysulfone (A) as a whole. You may adjust as follows.

The content of the terminal phenolic hydroxyl groups of the aromatic polysulfone (A2) is preferably 6 × 10 ⁻⁵ mol / g or more, more preferably 8 × 10 ⁻⁵ mol / g or more, preferably 2 × 10. ⁻⁴ mol / g or less, more preferably 1.7 × 10 ⁻⁴ mol / g or less. By being more than a lower limit, the effect by having used aromatic polysulfone (A2) becomes higher, and by being below an upper limit, the viscosity of the aromatic polysulfone composition mentioned later becomes higher, and also insulation coating. The mechanical strength of the layer is further improved. In addition, content of the terminal phenolic hydroxyl group shown here is the mole number in 1 g of aromatic polysulfone (A2) which has this phenolic hydroxyl group. The content of the terminal phenolic hydroxyl groups as described above in the aromatic polysulfone (A2) is suitable when the aromatic polysulfone (A1) is used in combination. As described later, the aromatic polysulfone composition has an aromatic content. This is particularly suitable when the content of polysulfone (A2) is set within a preferred range.

A commercially available product may be used as the aromatic polysulfone (A).
For example, examples of commercially available products of aromatic polysulfone (A1) include polyethersulfone “Sumika Excel 3600P”, “Sumika Excel 4100P”, “Sumika Excel 4800P”, and “Sumika Excel 5200P” manufactured by Sumitomo Chemical Co., Ltd. .
Moreover, as an example of a commercial item of aromatic polysulfone (A2), Sumitomo Chemical Co., Ltd. polyethersulfone “Sumika Excel 5003P” can be mentioned.

  The fluororesin (B) may be a resin containing a fluorine atom, and is preferably a fluorocarbon polymer. Examples thereof include polytetrafluoroethylene (PTFE) and polytetrafluoroethylene-hexafluoropropylene. Copolymer (FEP), polychlorotrifluoroethylene (PCTFE), polytrichlorofluoroethylene, polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), ethylene-tetrafluoroethylene copolymer (ETRE), ethylene-chloro Examples thereof include trifluoroethylene copolymer (ECTRE) and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA). PTFE is particularly preferred from the viewpoint of excellent heat resistance during processing.

  PTFE is preferably a powder having a volume average particle size of less than 20 μm. Examples of such commercially available products include Fullon L169J, Fullon L150J, Fullon L170J, Fullon L172J, and Fullon L173J (above, manufactured by Asahi Glass Co., Ltd.). , Lubron L-2, Lubron L-5, Lubron LD-1 (above, manufactured by Daikin Industries), Teflon (registered trademark) TLP-10, Teflon (registered trademark) TLP-10F-1 (above, manufactured by DuPont) Cefral Lube I, Cefral Lube IP, Cefral Lube V (above, manufactured by Central Glass Co., Ltd.), Dinion TF9205 (manufactured by Sumitomo 3M Limited), and the like.

The fluororesin (B) preferably has a flow start temperature of 350 ° C. or lower. The low molecular weight fluororesin (B) that exhibits such a flow initiation temperature has better compatibility with the aromatic polysulfone (A), and accordingly, in the aromatic polysulfone composition, the aromatic polysulfone ( The dispersibility of the fluororesin (B) in the matrix comprising A) is further improved.
Here, the flow start temperature of the fluororesin (B) is 4 ° C./min under a load of 9.81 MPa (100 kgf / cm ² ) using a capillary rheometer having a capillary with an inner diameter of 1 mm and a length of 10 mm. It is a temperature at which the melt viscosity exhibits 4800 Pa · s (48000 poise) when the heated melt is extruded from the nozzle while the temperature of the heated melt is raised.

  Examples of commercially available PTFE products having a flow start temperature of 350 ° C. or lower include Cefral Lube I, Cefral Lube IP (above, manufactured by Central Glass Co., Ltd.) and Dinion TF9205 (manufactured by Sumitomo 3M Limited).

In the present invention, the aromatic polysulfone composition contains an aromatic polysulfone (A) and a fluororesin (B). In the aromatic polysulfone composition, the total content of terminal phenolic hydroxyl groups of the aromatic polysulfone (A) is 3.0 × 10 ^{−5 to} 10.0 × 10 with respect to 1 g of the fluororesin (B). ⁻⁵ mol, preferably 4.0 × 10 ^{−5 to} 9.5 × 10 ⁻⁵ mol, and more preferably 4.0 × 10 ^{−5 to} 9.0 × 10 ⁻⁵ mol. By setting it to the lower limit value or more, the insulating coating layer is excellent in chemical resistance and scratch resistance, and has a high partial discharge start voltage and is stable. In addition, by setting the upper limit value or less, the viscosity of the aromatic polysulfone composition is moderately improved, and when the aromatic polysulfone composition is melt processed and molded, the residence stability is improved, Extrusion and the like can be performed more stably.

In the aromatic polysulfone composition, the content of the aromatic polysulfone (A) and the fluororesin (B) is not particularly limited as long as the total content of the terminal phenolic hydroxyl groups is in the above range, and is appropriately limited. Can be adjusted.
For example, when aromatic polysulfone (A1) and (A2) are used in combination as aromatic polysulfone (A), the content of aromatic polysulfone (A2) in the aromatic polysulfone composition is aromatic polysulfone (A1). It is preferably 5 parts by mass or more, preferably 50 parts by mass or less, and more preferably 20 parts by mass or less with respect to 100 parts by mass.
The content of the fluororesin (B) in the aromatic polysulfone composition is preferably 5 parts by mass or more and preferably 45 parts by mass or less with respect to 100 parts by mass of the aromatic polysulfone (A1). , 35 parts by mass or less, more preferably 30 parts by mass or less.

  In the range which does not impair the effect of this invention, an aromatic polysulfone composition is a filler, an additive, and aromatic polysulfone and fluorine other than aromatic polysulfone (A) and a fluororesin (B) as needed. One or more other components such as a resin other than the resin may be included. These other components may be added during processing of the aromatic polysulfone composition into a molded body (insulating coating layer).

  The filler may be either an organic filler or an inorganic filler, may be a fibrous filler, may be a plate-like filler, or may be a granular filler other than a fibrous or plate-like material. It may be.

Examples of fibrous inorganic fillers include glass fibers; carbon fibers such as pan-based carbon fibers and pitch-based carbon fibers; ceramic fibers such as silica fibers, alumina fibers and silica-alumina fibers; and metal fibers such as stainless steel fibers. . In addition, whiskers such as potassium titanate whisker, barium titanate whisker, wollastonite whisker, aluminum borate whisker, silicon nitride whisker, and silicon carbide whisker are also included.
Examples of the fibrous organic filler include polyester fibers and aramid fibers.
Examples of the plate-like inorganic filler include talc, mica, graphite, wollastonite, glass flake, barium sulfate, and calcium carbonate. The mica may be any of muscovite, phlogopite, fluorine phlogopite, and tetrasilicon mica.
Examples of granular fillers include glass beads, glass powder, hollow glass, kaolin, clay, vermiculite; calcium silicate, aluminum silicate, feldspar powder, acid clay, wax clay, sericite, sillimanite, bentonite, slate powder. Silicates such as silanes; carbonates such as calcium carbonate, pepper, barium carbonate, magnesium carbonate, dolomite; sulfates such as barite powder, blankfix, precipitated calcium sulfate, calcined gypsum, barium sulfate; hydrated alumina, etc. Hydroxides; alumina, antimony oxide, magnesia, titanium oxide, zinc oxide, silica, silica sand, quartz, white carbon, diatomaceous earth, etc .; sulfides such as molybdenum disulfide; nitrides such as boron nitride; silicon carbide Carbides such as; metal powder; organic polymer; organic such as brominated diphenyl ether Include those made of a material having a molecular weight of crystals or the like, included or spherical fillers, the aspect ratio is smaller powder particles.

  Examples of the additive include an antioxidant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, a flame retardant, a lubricant, an antistatic agent, an inorganic or organic colorant, a rust inhibitor, a crosslinking agent, a foaming agent, and a fluorescent agent. , Surface smoothing agents, surfactants, surface gloss improvers, mold release improvers.

  Examples of the resin include polypropylene, polyamide, liquid crystal polyester, polyester other than liquid crystal polyester, thermoplastic resin such as polyphenylene sulfide, polyether ketone, polycarbonate, polyphenylene ether, and polyetherimide; phenol resin, epoxy resin, polyimide resin, A thermosetting resin such as cyanate resin may be used.

  The aromatic polysulfone composition contains the aromatic polysulfone (A) and the fluororesin (B) in total, preferably 60% by mass or more, more preferably 80% by mass or more. The aromatic polysulfone (A) and the fluororesin (B ) Only. By setting the lower limit value or more, an insulating coating layer having the effects of the present invention more remarkably can be obtained.

  The aromatic polysulfone composition is obtained by blending the aromatic polysulfone (A), the fluororesin (B), and other components as necessary, and the content of the aromatic polysulfone (A) and the fluororesin (B). These components may be blended so that is in the above numerical range.

The production method of the aromatic polysulfone composition may be a known method and is not particularly limited. For example, a method of obtaining a composition by mixing each compounding component and dissolving or dispersing it in a solvent and evaporating the solvent from the liquid, or dropping the liquid into a poor solvent to form a composition And a method obtained by precipitation. From an industrial point of view, a method of kneading each compounding component in a molten state (melt kneading) is preferable.
The melt-kneading can be performed by a commonly used kneading apparatus such as a single-screw or twin-screw extruder or various kneaders. Among them, it is preferable to use an extruder, and as such an extruder, a cylinder, one or more screws arranged in the cylinder, and a supply port provided at one or more positions of the cylinder are provided. Those having a vent portion at one or more locations of the cylinder are more preferable, and a biaxial high-kneading extruder is particularly preferable. Using such an extruder, the blended components are melt-kneaded, and the extruded strand is continuously cut to obtain a pellet-shaped aromatic polysulfone composition.

In the production of the aromatic polysulfone composition, the order of addition during mixing or kneading of the blending components is not particularly limited. For example, after adding and mixing the fluororesin (B) to the aromatic polysulfone (A) in advance, the resulting mixture is put into a kneader and melt-kneaded, and the aromatic polysulfone (A) is added to the kneader. There is a method in which the fluororesin (B) is added and kneaded in the place where it is charged and melted.
Moreover, when using aromatic polysulfone (A1) and (A2) together as aromatic polysulfone (A), for example, aromatic polysulfone (A2) and fluororesin (B) are previously added to aromatic polysulfone (A1). After the addition and mixing, the resulting mixture is put into a kneading apparatus and melt-kneaded. Aromatic polysulfone (A1) is charged into the kneading apparatus and melted, and then aromatic polysulfone (A2) is added. ) And the fluororesin (B) and kneading the mixture, and the aromatic polysulfone (A2) and the liquid crystal polymer (B) are mixed into the kneading apparatus after the aromatic polysulfone (A2) is charged and melted. A method of charging and kneading, and a method of first charging the aromatic polysulfone (A1) and (A2) into the kneading apparatus and then charging and kneading the fluororesin (B). It is.

The insulating coating can be produced by coating the object to be coated with an insulating coating layer obtained using the aromatic polysulfone composition. Here, the “covering object” is usually a conductor.
As a method of coating a coating object with an insulating coating layer, for example, a method of coating a coating object with an insulating coating layer that has been molded in advance using an aromatic polysulfone composition (hereinafter referred to as “coating method 1”). And a method of forming an insulating coating layer from the aromatic polysulfone composition (hereinafter referred to as “coating method 2”) after coating the object to be coated with the aromatic polysulfone composition.

  As an example of the coating method 1, there is a method in which an insulating coating layer is pressure-bonded to an object to be coated by heating and pressing the formed insulating coating layer on the object to be coated. The conditions for the heating press at this time may be appropriately adjusted according to the types of the insulating coating layer and the coating target, and are not particularly limited.

  As an example of the coating method 2, there is a method of forming an insulating coating layer on a coating object by press-molding the aromatic polysulfone composition after coating the coating object with the aromatic polysulfone composition before molding. Can be mentioned. The press molding conditions at this time may be appropriately adjusted according to the types of the aromatic polysulfone composition and the coating target, and may be a hot press, and are not particularly limited. In addition, the aromatic polysulfone composition after coating the object to be coated does not necessarily need to be molded. For example, an aromatic polysulfone composition that is a liquid obtained by dissolving or dispersing each compounding component in a solvent is used. A method of forming an insulating coating layer on the coating target by removing the solvent from the aromatic polysulfone composition by evaporation or the like after coating the coating target with the above. Further, instead of removing the solvent, a method may be mentioned in which a poor solvent is brought into contact with the aromatic polysulfone composition covering the object to be coated, and the precipitate deposited on the object to be coated is used as an insulating coating layer.

  For example, as a method of manufacturing an insulation-coated electric wire as an insulation coating body by the coating method 2, a heating furnace that heats a conductor that becomes a core wire (electric wire) and a coating device that includes an extruder are continuously arranged. The method which has the process of coat | covering a core wire with an aromatic polysulfone composition using the used electric wire coating apparatus is mentioned. In this case, it is possible to coat while preparing the aromatic polysulfone composition in the extruder of the coating apparatus.

  The insulating coating according to the present invention has a sufficient chemical resistance, heat resistance, flame resistance, environmental resistance (moisture resistance) and insulating properties in addition to thermoplasticity in the insulating coating layer, and in addition to partial discharge. The starting voltage is high. Furthermore, it has excellent scratch resistance and flexibility. Therefore, the insulating coating according to the present invention is suitable for application to an insulating coated conductor such as a coil incorporated in various electric devices used under a high applied voltage. Furthermore, since the insulating coating layer is excellent in scratch resistance, it is particularly suitable for automatically manufacturing an insulating coating and assembling an apparatus using the insulating coating.

  Specific uses of the insulating coating according to the present invention include: electrical / electronic devices; OA devices; information terminal devices such as personal computers; game machines; display devices such as televisions; printers; Electronic notebook; PDA; Electronic desk calculator; Electronic dictionary; Camera; Video camera; Mobile phone; Smartphone; Drive or reading device for recording medium; Mouse: Numeric keypad; Disc player such as CD player, DVD player, Blu-ray player; Examples include a portable radio or portable audio player housing, cover, keyboard, button, switch, disc tray, disc cartridge, disc changer tray member, and the like. Vehicle exterior / external parts such as headlamps and helmet shields; vehicle interior parts such as inner door handles, center panels, instrument panels, console boxes, luggage floor boards, display housings (such as car navigation), and the like. In addition, as electrical / electronic parts, bobbins such as optical pickup bobbins and transformer bobbins; relay parts such as relay cases, relay bases, relay sprues and relay armatures; shield members for various connectors; reflectors such as lamp reflectors and LED reflectors; Holders such as lamp holders and heater holders; camera module parts; switch parts; motor parts; sensor parts; hard disk drive parts; dishware such as ovenware; vehicle parts; aircraft parts; various electric wires, motors, transformers, inverters, converters, etc. Examples include coil parts.

  Hereinafter, the present invention will be described in more detail with reference to specific examples. However, the present invention is not limited to the following examples. The reduced viscosity of the aromatic polysulfone (A) and the content of terminal phenolic hydroxyl groups of the aromatic polysulfone (A) were measured by the following methods.

(Measurement of reduced viscosity of aromatic polysulfone (A))
By dissolving 1 g of aromatic polysulfone (A) in N, N-dimethylformamide (DMF) and setting the volume to 1 dL, the solution has a concentration of 1% (w / v) (hereinafter referred to as “PES solution”). The reduced viscosity was measured in an environment of 25 ° C. using an Ostwald viscometer using this PES solution. The reduced viscosity was determined by the following formula.
Reduced viscosity = PES solution dropping time / DMF dropping time−1.00

(Measurement of content of terminal phenolic hydroxyl groups of aromatic polysulfone (A))
A predetermined amount of aromatic polysulfone (A) is dissolved in dimethylformamide, an excess amount of paratoluenesulfonic acid is added, and then a 0.05 mol / L potassium methoxide / toluene / methanol solution is added using a potentiometric titrator. After neutralizing the residual paratoluenesulfonic acid, the hydroxyl group was neutralized, and from the amount (mole number) of potassium methoxide required for neutralization of this hydroxyl group, the number of moles of the hydroxyl group was determined. This was determined by dividing by the predetermined amount (g) of aromatic polysulfone (A).

<Production of aromatic polysulfone (A)>
[Production Example 1]
In a polymerization tank having a capacity of 2000 mL equipped with a stirrer, a nitrogen gas introduction tube, a thermometer, and a condenser with a receiver at the tip, 620.3 g (2.16 mol) of 4,4′-dichlorodiphenylsulfone, After putting 525.0 g (2.10 mol) of 4,4′-dihydroxydiphenyl sulfone and 784.0 g of diphenyl sulfone as a polymerization solvent, the temperature was raised to 180 ° C. while flowing nitrogen gas through the system, and then anhydrous potassium carbonate 301.8 g was added, the temperature was gradually raised to 290 ° C., and the mixture was reacted at 290 ° C. for 2 hours. After completion of the reaction, the reaction solution was cooled to room temperature, and the solidified reaction mass was finely pulverized and then washed with warm water to remove potassium chloride. Further, washing with a mixed solvent of acetone and methanol is performed several times to remove diphenylsulfone as a polymerization solvent, followed by washing with water, followed by heating and drying at 150 ° C. to obtain powdered aromatic polysulfone (A1) As a result, aromatic polysulfone (A1) -1 was obtained. The central particle size of the aromatic polysulfone (A1) -1 was 500 μm, and the reduced viscosity was 0.48.

<Manufacture of insulation coating>
[Examples 1 and 2, Comparative Examples 1 to 6]
(Production of aromatic polysulfone composition)
Each component shown in Tables 1 and 2 was weighed and blended in the proportions shown in Tables 1 and 2, then blended at 25 ° C. for 30 minutes using a tumbler mixer, and then a twin screw extruder (“PCM” manufactured by Ikekai Tekko Co., Ltd.). -30 "), this blend was granulated at a cylinder temperature of 340 ° C to obtain pellets of an aromatic polysulfone composition.
In Tables 1 and 2, “-” in the column of the blending component means that the component is not blended. In Tables 1 and 2, “aromatic polysulfone (A2) -1”, “fluororesin (B) -1” and “fluororesin (B) -2” mean the following, respectively. Tables 1 and 2 show the number of moles (mol / g) of the terminal phenolic hydroxyl groups per gram of the fluororesin (B) in the aromatic polysulfone composition, “number of moles of hydroxyl groups / fluororesin”. It is shown together as “(B) amount (× 10 ⁻⁵ mol / g)”.
Aromatic polysulfone (A2) -1: polyethersulfone “SUMICA EXCEL 5003PS” manufactured by Sumitomo Chemical Co., Ltd. (having 8.6 × 10 ⁻⁵ mol / g of terminal phenolic hydroxyl groups, and reduced viscosity of 0.51 dl / g) What is)
Fluororesin (B) -1: “Dinion TF9205” manufactured by Sumitomo 3M Limited (flow start temperature: 330 ° C.)
Fluororesin (B) -2: “Fullon L169J” manufactured by Asahi Glass Co., Ltd. (flow start temperature: 352 ° C.)

(Manufacture of insulation coating)
The obtained pellets of the aromatic polysulfone composition were dried at 120 ° C. for 3 hours, and then pelleted at a cylinder temperature of 360 ° C. and a mold temperature of 150 ° C. using an injection molding machine (“UH-1000 type” manufactured by Nissei Plastic Industries). Was molded by injection to produce a molded body (1) (insulating coating layer (1)) of 125 mm × 13 mm × 1.6 mm. Then, a 1 mm thick aluminum plate cut out to a size of 125 mm × 13 mm is heated to 250 ° C., and the surface of the produced insulating coating layer (1) is laminated on the surface thereof in a uniform direction so as to be crimped. An insulating coating was produced.

<Evaluation of insulation coating layer>
(chemical resistance)
The obtained insulating coating is mounted on a jig with a span of 100 mm so that the aluminum plate is on the lower side, and the central part is displaced 20 mm from the lower side to the upper side of the insulating coating, and R = 72.5 mm Then, methyl ethyl ketone (MEK) was applied to the entire surface of the insulating coating layer (1), and the change in the insulating coating layer (1) was visually observed to evaluate chemical resistance. The results are shown in Tables 1 and 2. In Tables 1 and 2, the abbreviations of the chemical resistance evaluation results mean the following. In addition, “-” in the evaluation result column means that it has not been evaluated. The same applies to “dispersibility” and “flexural modulus (flexibility)” described below.
R1S: The insulating coating layer (1) cracked in 1 second after applying MEK.
R3S: The insulating coating layer (1) was cracked in 3 seconds after applying MEK.
R4S: The insulating coating layer (1) was cracked 4 seconds after the MEK application.

(Dispersibility)
Separately from the production of the insulation coating, a molded body (2) (insulation coating layer (2)) was produced by the following method.
That is, the pellets of the aromatic polysulfone composition obtained in Example 1 were dried at 120 ° C. for 3 hours, and then an injection molding machine (“UH-1000 type” manufactured by Nissei Plastic Industry Co., Ltd.) was used. Pellets were injection molded at a mold temperature of 150 ° C. to produce a molded body (2) (insulating coating layer (2)) serving as a test piece. And the external appearance of this molded object (2) was observed visually, and the dispersibility of the aromatic polysulfone composition was evaluated. The results are shown in Tables 1 and 2. In Tables 1 and 2, the abbreviations for the evaluation results of the dispersibility of the aromatic polysulfone composition mean the following.
(Circle): The external appearance of the molded object (2) was uniform, and it has shown that the dispersibility of the aromatic polysulfone composition was favorable.
X: The appearance of the molded body (2) was non-uniform, indicating that the dispersibility of the aromatic polysulfone composition was inferior.

(Bending elastic modulus (flexibility))
Moreover, the bending elastic modulus (MPa) was calculated | required about the molded object (2) based on ASTMD790. The results are shown in Tables 1 and 2.

As is clear from the above results, the insulating coatings of Examples 1 and 2 did not generate cracks in the insulating coating layer, and were excellent in chemical resistance. Further, the appearance of the molded body (2) was uniform, no aggregation of the fluororesin (B) was observed, and the dispersibility of the aromatic polysulfone composition was good, that is, the molded body (2) was It showed excellent scratch resistance. Moreover, the bending elastic modulus was low and the molded body (2) also had flexibility.
On the other hand, the insulation coating bodies of Comparative Examples 1 to 5 were cracked in the insulation coating layer in a short time, and the insulation coating layer was inferior in chemical resistance. This is because aromatic polysulfone (A1) -1 and (A2) -1 are not used in combination in the aromatic polysulfone composition (Comparative Examples 1 to 4), or the content of the fluororesin (B) is too large. (Comparative Example 5). Moreover, the external appearances of the molded bodies (2) of Comparative Examples 2 to 4 were uneven, aggregation of the fluororesin (B) was observed, and the dispersibility of the aromatic polysulfone composition was inferior, that is, the molded bodies. (2) was inferior in scratch resistance. This was considered to be caused by not using aromatic polysulfone (A2) -1 in the aromatic polysulfone composition. Moreover, the molded object (2) of the comparative examples 1 and 4 had a high bending elastic modulus, and was inferior to the softness | flexibility. This is because, in the aromatic polysulfone composition, the fluororesin (B) is not used (Comparative Example 1) or the content of the fluororesin (B) is too small (Comparative Example 4). it was thought.

  INDUSTRIAL APPLICABILITY The present invention can be used for an insulation coated conductor incorporated in various electric devices used under a condition where the applied voltage is high.

Claims (5)

An insulating coating obtained by coating an object to be coated with an insulating coating layer obtained by using an aromatic polysulfone composition containing an aromatic polysulfone (A) and a fluororesin (B),
In the aromatic polysulfone composition, the total content of phenolic hydroxyl groups and salts of phenolic hydroxyl groups present at the ends of the chain structure of the aromatic polysulfone (A) is 1 g of the fluororesin (B). Insulation covering body characterized by being 3.0 × 10 ^{−5 to} 10.0 × 10 ⁻⁵ mol.   The insulation coating body according to claim 1, wherein the flow starting temperature of the fluororesin (B) is 350 ° C or lower. In the aromatic polysulfone composition, the total content of phenolic hydroxyl groups and salts of phenolic hydroxyl groups present at the ends of the chain structure of the aromatic polysulfone (A) is 1 g of the fluororesin (B). insulating coating material according to claim 1 or 2, characterized in that it is 4.0 × ^{10 -5} ~9.0 × ¹⁰ -5 mol Te. The said insulating polysulfone (A) has a repeating unit represented by following General formula (1), The insulation coating body as described in any one of Claims 1-3 characterized by the above-mentioned.
(1) -Ph ¹ -SO ₂ -Ph ² -O-
(In the formula, Ph ¹ and Ph ² are each independently a phenylene group, and one or more hydrogen atoms of the phenylene group may be each independently substituted with an alkyl group, an aryl group, or a halogen atom.) An aromatic polysulfone (A2) having a phenolic hydroxyl group and / or a salt of a phenolic hydroxyl group at the end of the chain structure, an aromatic polysulfone (A1) not corresponding to the aromatic polysulfone (A2), a fluororesin ( B) and an aromatic polysulfone composition prepared by blending, and an insulating coating layer formed by using the aromatic polysulfone composition, and a method for producing an insulating coating for covering an object to be coated,
In the aromatic polysulfone composition, the blending amount of the aromatic polysulfone (A1) is 100 parts by mass and the blending amount of the fluororesin (B) is 5-45 parts by mass. The total content of the phenolic hydroxyl group and the salt of the phenolic hydroxyl group present at the end of the structure is 3.0 × 10 ^{−5 to} 10.0 × 10 ⁻⁵ mol with respect to 1 g of the fluororesin (B). A method for producing an insulating covering, characterized in that