JP2011014510A - Insulated wire and terminal processing method for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an insulated wire, in which a conductor is coated with an urethane resin, and removing of coating is easier, and a terminal processing method for the same.SOLUTION: The insulated wire is formed by coating the conductor with an ultraviolet curing type urethane acrylate resin having a gel fraction of 80% or more, a glass transition temperature of 50°C or more and 130°C or less, and a Young's modulus of 100 MPa or more and 700 MPa or less. In the insulated wire, a coating material 1 can be removed by being dipped in an organic solvent, thereby a terminal processing can be made easier.

Description

  The present invention relates to an insulated wire having an insulating coating of urethane resin and a method for treating the end thereof.

  As a means for obtaining an insulated wire having a thin film insulation coating on a conductor, which is used in coils of generators, motors, transformers, etc., a method of applying a liquid material and curing it is well known.

  Examples of the liquid material include a thermosetting type, an ultraviolet curable type, and an electron beam curable type, and among them, an insulated wire using a thermosetting material is often used.

  However, an insulated wire coated with a thermosetting resin is poor in productivity because the coating and baking processes are repeated several times until the required thickness is reached, and the liquid resin used contains 50% or more of an organic solvent. Therefore, there is a problem that equipment for recovering the vaporized organic solvent generated in the baking process is required.

  On the other hand, the production method using an ultraviolet curable resin has high productivity because the resin has a high curing speed and a necessary thickness can be obtained by one application.

  By the way, since the terminal of the coil using these insulated wires is mainly joined by soldering, the covering material of the insulated wires must be removed in advance.

  As a method for removing the insulation wire coated with thermosetting resin, (A) mechanical removal with a metal brush or wire stripper, (B) removal with a remover such as acid or alkaline solution, (C) direct immersion in a solder bath There is a removal to do. A similar method is also used for coating removal of an insulated wire coated with an ultraviolet curable resin, Patent Document 1 discloses a wire that can be removed by a wire stripper, and Patent Document 2 describes a coating removal method using a chlorinated organic solvent. Patent Document 3 discloses an insulated wire capable of removing solder at low temperature.

Japanese Patent Laid-Open No. 04-192213 JP 07-238273 A Japanese Unexamined Patent Publication No. 07-057548

  However, (A) Mechanical removal with a metal brush or wire stripper tends to damage the conductor. (B) Since removal using a remover uses highly corrosive acid and alkaline solutions, if the remover remains on the conductor, it may be a factor that degrades the coating material and the conductor. In addition, a decomposition product of the coating material remains on the conductor, and a cleaning process must be provided. (C) Since the removal by immersing directly in the solder bath is immersed in a high-temperature solder bath, the thermal decomposition product of the coating material tends to remain on the conductor, and the conductor thinning due to thermal deterioration or melting of the coating material around the solder immersion Each has its own problems.

  In addition, in the terminal treatment of the insulation coated assembly wire that combines multiple insulated wires, the insulation coating assembly wire is twisted back and stripped by one of the above-mentioned coating removal methods one by one with the wrinkles removed. After the insulation removal, the insulation coating assembly wire has to be returned to the original state in order to be connected, which is very troublesome.

  An object of the present invention is to provide an insulated wire coated with an ultraviolet curable urethane acrylate resin that can be easily removed from the coating, and a terminal treatment method thereof.

The present invention is as follows.
(1) An insulated wire in which a conductor is coated with an ultraviolet curable urethane acrylate resin, and the ultraviolet curable urethane acrylate resin has a gel fraction of 80% or more, a glass transition temperature of 50 ° C. or more and 130 ° C. or less, Young's modulus Is a range of 100 MPa or more and 700 MPa or less. (2) The insulated wire according to (1), wherein the conductor is copper or aluminum. (3) A terminal treatment method in which the insulated wire described in (1) is immersed in an organic solvent having a solubility parameter (SP value) in the range of 8.0 to 14.5 to remove the coating.

  When the insulated wire coated with the UV curable urethane acrylate resin according to the present invention is dipped in an organic solvent, the insulated wire is taken out from the organic solvent, and the dipped portion is sandwiched with a cloth and pulled out, the covering material is easily sheathed and pulled out. And no coating material remains on the conductor.

  Further, by using an organic solvent having a solubility parameter (SP value) of 8.0 to 14.5, the coating can be removed within 300 seconds after immersion at room temperature.

  Furthermore, in the insulation-covered aggregated wire in which a plurality of insulated wires according to the present invention are combined, it is immersed in an organic solvent in a state where the gap is provided between the insulated wires, and is removed, and removed by a plastic brush or suction of the coating material It is possible to remove the coating by means of the above, and it is possible to easily restore the insulation coated aggregated wire at the time of connection because it leaves more wrinkles.

It is sectional drawing of the insulated wire of this invention. It is sectional drawing of the insulation coating assembly line which matched the insulated wire of this invention more.

  Next, the form for implementing this invention is demonstrated. The ultraviolet curable urethane acrylate resin of the coating material is obtained from a urethane acrylate oligomer, an ethylenically unsaturated monomer, and a photoinitiator. The urethane acrylate oligomer can be obtained by reacting diisocyanate with hydroxy acrylate and a polyol.

  Examples of the diisocyanate include tolylene diisocyanate, 4,4-diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, methylene bis (4-cyclohexyl isocyanate), and one or more diisocyanates are used.

  Examples of the polyol include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and the like, trimethylolpropane, glycerin, pentaerythritol, sorbitol, sucrose, quadrol and other polyhydric alcohols, ethylene oxide, propylene oxide, and the like. Polyether polyol obtained by addition reaction with cyclic ether compounds such as butylene oxide and tetrahydrofuran, polycaprolactone polyol obtained by reacting the above polyhydric alcohol with caprolactone, polyhydric alcohol, dibasic acid and diol The polyester polyol obtained by making it react with the polyester which can be mentioned, 1 type, or 2 or more types of polyol is used

  Examples of the hydroxy acrylate include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, pentaerythritol triacrylate, glycidyl methacrylate, and the like, and one or more hydroxy acrylates are used.

  The ethylenically unsaturated monomer is a compound having an ethylenically unsaturated bond (C = C) in the molecule, a monofunctional monomer having one ethylenically unsaturated bond in one molecule, or in one molecule A polyfunctional monomer having two or more ethylenically unsaturated bonds is used.

  Examples of the monofunctional monomer include acrylamide, (meth) acryloylmorpholine, 7-amino-3,7-dimethyloctyl (meth) acrylate, isobutoxymethyl (meth) acrylamide, isobornyloxyethyl (meth) acrylate, Isobornyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ethyldiethylene glycol (meth) acrylate, t-octyl (meth) acrylamide, diacetone (meth) acrylamide, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, Lauryl (meth) acrylate, dicyclopentadiene (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, dicyclopentenyl (meth) acrylate N, N-dimethyl (meth) acrylamide tetrachlorophenyl (meth) acrylate, 2-tetrachlorophenoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, tetrabromophenyl (meth) acrylate, 2-tetrabromophenoxyethyl (Meth) acrylate, 2-trichlorophenoxyethyl (meth) acrylate, tribromophenyl (meth) acrylate, 2-tribromophenoxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) Acrylate, vinylcaprolactam, N-vinylpyrrolidone, phenoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, pentachlorophenyl (meth) acrylate Pentabromophenyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, bornyl (meth) acrylate, methyl triethylene diglycol (meth) acrylate, and the like.

  Examples of the polyfunctional monomer include ethylene glycol di (meth) acrylate, dicyclopentenyl di (meth) acrylate, triethylene glycol diacrylate, tetraethylene glycol di (meth) acrylate, tricyclodecanediyldimethylene di ( (Meth) acrylate, tris (2-hydroxyethyl) isocyanurate di (meth) acrylate, tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, caprolactone-modified tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate , Trimethylolpropane tri (meth) acrylate, ethylene oxide modified trimethylolpropane tri (meth) acrylate, propylene oxide modified trimethylolpropane tri ( ) Acrylate, tripropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, bisphenol A diglycidyl ether end (meth) acrylic acid adduct, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, polyester di (meth) acrylate, polyethylene glycol di (meth) acrylate, dipentaerythritol hexa (meth) Acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol tetra (meth) acrylate, caprolactone-modified dipentaerythritol hexa (meth) acrylate DOO, caprolactone-modified dipentaerythritol penta (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, ethylene oxide-modified bisphenol A di (meth) acrylate.

  A plurality of these monofunctional and polyfunctional monomers can be used in combination.

  A known photoinitiator can be used for the ultraviolet curable urethane acrylate resin. For example, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, 1-hydroxycyclohexyl phenyl ketone, benzyl dimethyl ketal, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one, Benzophenone, benzoin ester, benzoin ether and the like, and one or more photoinitiators are used.

  In the implementation, an ultraviolet curable urethane acrylate resin is added to an antioxidant, a photopolymerization aid, a filler, a plasticizer, a non-reactive polymer, a colorant, an anti-softening agent, a lubricant, a dispersant, an antistatic agent, an electrostatic agent. Combination agents such as an inhibitor, an anti-blocking agent, and an adhesion aid can be contained in combination.

  The insulated wire of the present invention is obtained by a process in which an ultraviolet curable urethane acrylate resin is applied on a conductor, excess liquid resin is squeezed out using a die, and ultraviolet light is irradiated to cure the liquid resin. Examples of the ultraviolet irradiation means include a method of irradiating ultraviolet rays from the entire circumference of the conductor from an ultraviolet light source such as a high pressure mercury lamp, a halogen lamp, or a xenon lamp.

  The gel fraction of the ultraviolet curable urethane acrylate resin according to the present invention is preferably 80% or more. When the gel fraction is 80% or more, the resin strength after immersion in the organic solvent is sufficiently maintained, and the coating material can be removed without being cut off during the coating removal.

  The Young's modulus of the ultraviolet curable urethane acrylate resin according to the present invention is preferably in the range of 100 MPa to 700 MPa. Resins within this range can ensure the appropriate flexibility required for insulated wires. Since a resin having a low Young's modulus is soft, an appropriate hardness as a covering material for an insulated wire cannot be obtained. Further, when the coating is removed, the coating material in the immersion part is cut off halfway, and the coating material tends to remain on the conductor. On the other hand, in a resin having a high Young's modulus, the conductor and the coating material are easily peeled off or the coating material is easily cracked in the flexibility evaluated by the self-diameter winding test and the adhesion evaluated by the rapid extension test.

  The glass transition temperature of the ultraviolet curable urethane acrylate resin according to the present invention is preferably in the range of 50 ° C. or higher and 130 ° C. or lower. Since a resin having a low glass transition temperature is inferior in heat resistance softening property, it becomes soft at the operating temperature when the coil is energized, and an appropriate hardness cannot be obtained. In addition, a resin having a high glass transition temperature is hard to penetrate an organic solvent, and cannot be removed by coating at room temperature within 300 seconds after immersion.

  The organic solvent preferably has a solubility parameter (SP value) in the range of 8.0 to 14.5. For example, alcohol solvents such as methyl alcohol, ethyl alcohol, isopropyl alcohol, t-butyl alcohol and 1-butanol, ketone solvents such as acetone and methyl ethyl ketone, ester solvents such as ethyl acetate and butyl acetate, pyridine, and dimethyl Examples thereof include nitrogen-based solvents such as formamide, or mixed solvents thereof. Further, those having a solubility parameter (SP value) in the range of 8.5 to 12.0 are preferable because the coating can be removed within 120 seconds after immersion at room temperature. The coating removal can be performed under either heating or cooling conditions. However, for safety and health, a highly toxic halogen-based solvent represented by a chlorinated solvent is not preferable, and an organic solvent having low toxicity and low volatility is preferable. Among the organic solvents mentioned, nitrogen-based solvents can be preferably used.

  The material of the conductor may be a metal, and examples thereof include copper, aluminum, iron, platinum, silver, and other alloys. Further, the conductor may be plated with silver, tin, zinc, nickel or the like. Among these materials, copper having good conductivity and aluminum employed as a conductor for reducing weight are suitable.

  The Example and comparative example of the insulated wire of this invention are demonstrated.

    Examples 1-6, Comparative Examples 1-5 apply UV curable urethane acrylate resins with different gel fraction, glass transition temperature, Young's modulus on aluminum having a conductor diameter of φ1.8 mm and copper having a conductor diameter of φ1.2 mm, Excess resin was squeezed out with a die and irradiated with ultraviolet rays to produce an insulated wire. The results of each test are shown in Table 1. The UV curable urethane acrylate resins used in Examples and Comparative Examples are as follows: Example 1: Model name KF2757 (manufactured by JSR), Example 2: Model name KF2753 (manufactured by JSR), Example 3: Model name KF2758 ( Example 4: Model name KF2754 (manufactured by JSR), Example 5: Model name KF2756 (manufactured by JSR), Example 6: Model name KF2757 (manufactured by JSR), Comparative example 1: Model name R3201 (manufactured by JSR), comparative example 2: model name FC5Y34 (manufactured by Dainippon Ink & Chemicals), comparative example 3: model name KF2751 (manufactured by JSR), comparative example 4: model name R2088 (manufactured by JSR), Comparative Example 5: Model name F2713 (manufactured by JSR).

  The test methods described in Table 1 are as follows.

1. Method for measuring gel fraction: The mass (W1) before extraction of the coating material was measured, and this sample was put into a Soxhlet extractor and extracted with methyl ethyl ketone (boiling point 80 ° C.) for 5 hours. The heating rate was a rate of circulating 10 to 20 times per hour. The mass (W2) after extraction was measured, and the gel fraction of the coating material was calculated according to the following formula.
Gel fraction (%) = mass after extraction (W2) / mass before extraction (W1) × 100

2. Glass transition temperature measurement: Measured with a rigid pendulum type physical property tester RPT-3000 manufactured by A & D. The temperature of the tester was adjusted to 0 ° C. in advance, and after setting the sample, the temperature was increased to 200 ° C. at a rate of 10 ° C./min. While the sample was heated, the logarithmic decay rate of the pendulum vibration was measured, and the temperature of the logarithmic decay rate peak was read as the glass transition temperature.

3. Young's modulus: An ultraviolet curable urethane acrylate resin was applied with a spin coater whose rotational speed was adjusted to a thickness of 200 μm, and irradiated with 1 J / cm 2 of ultraviolet light in a nitrogen stream. The resulting resin film was JIS K The Young's modulus at 2.5% elongation was calculated with a dumbbell of No. 7113, punched with a test temperature of 23 ° C., and a humidity of 50% at a tensile speed of 1 mm / min.

4). Flexibility: A self-diameter winding test was conducted based on the test method B method described in JISC3003. A mandrel having the same diameter as that of the prepared insulated wire was wound 10 times, and the coating material was checked with a magnifying glass for cracks. Those with no cracks were judged good, and those with no cracks were rejected.

5. Adhesiveness: A rapid extension test was performed based on the test method described in JISC3003. With a magnifying glass, the presence or absence of cracks and floating of the insulating coating was confirmed, and the peeling state of the coating material was confirmed from the fractured portion. A coating material that did not float was regarded as good, and a certain material was rejected.

6). Dielectric breakdown: A test was conducted based on the method from two described in JISC3003.

7. Coating removal test: The test temperature was 23 ° C., a test piece of 300 mm insulated wire was immersed 100 mm in the organic solvent shown in Table 1, and the covered portion of the insulated wire taken out after 300 seconds was sandwiched with a cloth to remove the coating. . Those that could be removed were marked with ◯, those that could not be removed were marked with ×, and those that could be removed but the coating material remained on the conductor were marked with Δ. Moreover, the shortest immersion time was investigated for the sample which was able to remove the coating.

  In the coating removal test, by immersing in an organic solvent having a solubility parameter (SP value) of 8.0 to 14.5, Examples 1 to 6 can remove the coating material within an immersion time of 300 seconds. Yes, the coating material can be pulled out in the form of a sheath, leaving no coating material on the conductor. On the other hand, in the case of a resin having a higher Young's modulus than Comparative Examples 1 and 2, the coating material floats from the conductor in the self-diameter winding test and the rapid extension test. Moreover, when the glass transition temperature was higher than that of Comparative Example 2, the coating could not be removed after an immersion time of 300 seconds. In Comparative Examples 3, 4, and 5, if any of the properties of gel fraction, glass transition temperature, and Young's modulus is out of the range, the coating can be removed. It remains on the conductor.

  Insulated electric wires coated with an ultraviolet curable urethane acrylate resin, an insulated electric wire that can be easily removed, and a terminal processing method thereof, and end processing operations such as coils are facilitated.

1: Coating material 2: Conductor

Claims (3)

    An insulated wire in which an ultraviolet curable urethane acrylate resin is coated on a conductor, and the ultraviolet curable urethane acrylate resin has a gel fraction of 80% or more, a glass transition temperature of 50 ° C. or higher and 130 ° C. or lower, and a Young's modulus of 100 MPa. The insulated wire is characterized by being in the range of 700 MPa or less.   The insulated wire according to claim 1, wherein the conductor is copper or aluminum. A terminal treatment method for removing the coating by immersing the insulated wire according to claim 1 in an organic solvent having a solubility parameter (SP value) in the range of 8.0 to 14.5.