JP2015183107A - Photocurable composition and terminal-provided covered conductor using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photocurable composition which is invulnerable to reaction inhibition by oxygen even in the atmosphere and secures sufficient hardening of a resin constituting the surface of a film. a terminal-provided covered conductor using it.SOLUTION: A photocurable composition comprises (A) a (meth)acrylic monomer and/or a (meth)acrylic oligomer, (B) hydrogen abstraction type photopolymerization initiator and (C) a tertiary amine having a methylene group or a methine group bonded to an N atom, and a copper plate/acrylic board superposition tensile shear strength of its hardened product, measured by JIS K6850, is 0.5 MPa or higher. In a terminal-provided covered conductor 1, an electric connection part 6 in which a terminal metal fitting 5 is connected electrically with a wire conductor 3 of the covered conductor 2 is covered with a hardened product of the photocurable composition.

Description

  The present invention relates to a photocurable composition and a coated electric wire with a terminal using the same, and more specifically, a photocurable composition suitable as an anticorrosive composition for an electrical connection portion of an electric wire conductor and a terminal fitting, and the use thereof It relates to a covered electric wire with a terminal.

  A terminal fitting is connected to the wire conductor at the end of the covered wire that is routed in a vehicle such as an automobile. In order to prevent corrosion at the electrical connection portion where the terminal fitting and the wire conductor of the covered electric wire are electrically connected, for example, Patent Document 1 discloses a connector in which the terminal fitting connected to the wire conductor is inserted and locked. A technique for injecting grease is disclosed.

Japanese Patent Laid-Open No. 05-159846

  In recent years, for the purpose of reducing the weight of a vehicle such as an automobile, the use of aluminum or an aluminum alloy as a material for a wire conductor has been studied. On the other hand, copper or a copper alloy is often used as a material for the terminal fitting. Further, the surface of the terminal fitting is often subjected to plating such as tin plating. In other words, the wire conductor and the terminal fitting may be made of different materials. If the wire conductor and the terminal fitting are made of different materials, corrosion due to contact with different metals occurs at the electrical connection portion. For this reason, it is calculated | required that an electrical connection part should carry out corrosion prevention reliably.

  Conventionally used grease cannot sufficiently prevent the ingress of water unless it is densely injected into the connector. If an attempt is made to increase the filling amount of grease in order to enhance the anticorrosion effect, the grease will be applied even to a portion where the anticorrosion is not originally required. Furthermore, excessive filling causes stickiness of the connector and the electric wire, and deteriorates handleability.

  Therefore, it is conceivable to use a resin as an anticorrosive agent instead of grease. When a radical reaction type ultraviolet curable resin is used as the resin, the surface of the coating film exposed to the air is likely to be inhibited by oxygen, and the resin on the coating surface may not be sufficiently cured. When the terminal fitting connected to the wire conductor is inserted into the connector housing in this state, the coating surface that is not sufficiently cured comes into contact with the inner surface of the connector housing. Then, when the coating surface is dried by the influence of heat generated at the place of wiring and the coating surface is hardened, the coating surface adheres to the inner surface of the connector housing. If it does so, when the terminal metal fitting connected to the electric wire conductor by repair etc. is pulled out from a connector housing, the resin coat may peel from the electric connection part of an electric wire conductor and a terminal metal fitting, and there exists a possibility that the anticorrosion function may be lost. In order to carry out the curing reaction of the UV curable resin under non-oxygen, it is necessary to add equipment for that purpose, and it is difficult to receive reaction inhibition by oxygen even under the atmosphere, and measures to sufficiently cure the resin on the coating surface are required. .

  The problem to be solved by the present invention is a photocurable composition that is less susceptible to reaction inhibition by oxygen even in the atmosphere, can sufficiently cure the resin on the surface of the film, and is excellent in anticorrosion performance, and a coated electric wire with a terminal using the same Is to provide.

In order to solve the above-mentioned problems, a photocurable composition according to the present invention contains the following components (A) to (C), and is a laminate of a copper plate and an acrylic plate measured according to JIS K6850 of the cured product. The gist is that the combined tensile shear strength is 0.5 MPa or more.
(A) (Meth) acrylic monomer and / or (meth) acrylic oligomer (B) Hydrogen abstraction type photopolymerization initiator (C) Tertiary amine having methylene group or methine group bonded to N atom

  Examples of the component (B) include benzophenones and thioxanthones. Moreover, as said (C) component, the tertiary alkylamine which has a methylene group or methine group couple | bonded with N atom is mentioned.

  The content of the component (C) is preferably in the range of 0.5 to 6 parts by mass with respect to 100 parts by mass of the (A).

  And the covered electric wire with a terminal concerning the present invention is that the electric connection part where the terminal metal fitting and the electric wire conductor of the covered electric wire were electrically connected was covered with the hardened material of the above-mentioned photocurable composition. It is a summary.

  In this case, it is preferable that the base metal of the terminal fitting is made of copper or a copper alloy, the wire conductor of the covered electric wire is made of aluminum or an aluminum alloy, and these electrical connection portions are different metal contact portions.

  According to the photocurable composition according to the present invention, in the photocurable composition containing (A) (meth) acrylic monomer and / or (meth) acrylic oligomer and (B) hydrogen abstraction type photopolymerization initiator, Further, (C) by containing a tertiary amine having a methylene group or a methine group bonded to an N atom, the reaction on the surface of the coating can be sufficiently cured even under atmospheric conditions, and the resin on the coating surface can be sufficiently cured. And the superposition | polymerization tensile shear strength of the copper plate and acrylic board which are measured based on JISK6850 of the hardened | cured material is 0.5 Mpa or more, It is excellent in the adhesiveness to a to-be-adhered material, and is anticorrosion as an anticorrosive. The performance can be fully demonstrated and the corrosion resistance is also excellent.

  In this case, when the content of the component (C) is in the range of 0.5 to 6 parts by mass with respect to 100 parts by mass of (A), the effect of suppressing reaction inhibition is excellent, and adhesion to the adherend is excellent. The deterioration can also be suppressed, and the anticorrosion performance as an anticorrosive can be sufficiently exhibited.

  And, according to the covered electric wire with a terminal according to the present invention, the electrical connection portion in which the terminal fitting and the electric wire conductor of the covered electric wire are electrically connected is covered with the cured product of the photocurable composition, Since the resin on the surface of the coating is also sufficiently cured, there is no problem of the coating surface adhering to the inner surface of the connector housing when the terminal fitting connected to the wire conductor is inserted into the connector housing. Even if the terminal fitting connected to the conductor is pulled out from the connector housing, there is no possibility that the resin coating is peeled off from the electric connection portion between the wire conductor and the terminal fitting. Thereby, an anticorrosion function can be maintained.

It is an external appearance perspective view of an example of the covered electric wire with a terminal of the present invention. FIG. 2 is a longitudinal sectional view taken along line AA in FIG. 1. It is explanatory drawing for demonstrating a shear adhesion test method. It is explanatory drawing for demonstrating a corrosion test method.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

The photocurable composition according to the present invention contains the following components (A) to (C).
(A) (meth) acryl monomer and / or (meth) acryl oligomer (B) hydrogen abstraction type photopolymerization initiator (C) tertiary amine having methylene group or methine group bonded to N atom Such a photocurable composition has a laminated tensile shear strength of 0.5 MPa or more of a copper plate and an acrylic plate measured according to JIS K6850 of the cured product.

  The component (A) is a (meth) acryl monomer and / or a (meth) acryl oligomer. Since the component (A) has a (meth) acryl group, it has high adhesion to a metal. Therefore, it is excellent in adhesiveness with a terminal metal fitting and an electric wire conductor. For this reason, adhesiveness with a terminal metal fitting or an electric wire conductor is securable.

  The component (A) is preferably liquid at 25 ° C. When it is liquid at 25 ° C., the composition is easily applied to the surface of the wire conductor, the surface of the insulating coating, and the surface of the terminal fitting. Moreover, it makes it easy to osmose | permeate a composition between the strands of an electric wire conductor, between an electric wire conductor and a terminal metal fitting, and between an electric wire conductor and insulation coating. For this reason, the workability | operativity of a composition and corrosion resistance can be improved. Since the component (A) is liquid at 25 ° C., the composition can be applied at room temperature. This makes it possible to apply the composition without heating. However, the composition may be applied without heating, may be applied by heating to adjust the viscosity, or may be applied after being dissolved in an appropriate solvent.

  The component (A) is a (meth) acrylic monomer or a (meth) acrylic oligomer, and is used in combination with the component (B), so that the composition can be cured after coating. For this reason, the applicability | paintability and shape stability of a composition can be made compatible.

  The (meth) acryl monomer may be mono (meth) acrylate or poly (meth) acrylate. A combination of these may also be used.

  Mono (meth) acrylates include isobornyl (meth) acrylate, bornyl (meth) acrylate, tricyclodecanyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, cyclohexyl (meth) Acrylate, (meth) acrylic acid, benzyl (meth) acrylate, 4-butylcyclohexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, Methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, noni (Meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate, tetrahydrofur Furyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, methoxyethylene glycol (meth) acrylate, ethoxyethyl (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, methoxypolypropylene glycol (meta ) Acrylate, polyoxyethylene nonylphenyl ether acrylate and the like. These may be used alone or in combination of two or more.

  Poly (meth) acrylates include butanediol di (meth) acrylate, hexanediol di (meth) acrylate, nonanediol di (meth) acrylate, decanediol di (meth) acrylate, 2-butyl-2-ethyl-1, 3-propanediol di (meth) acrylate, 2-hydroxy-3-acryloyloxypropyl methacrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetra Ethylene glycol di (meth) acrylate, tricyclodecane dimethylol di (meth) acrylate, 1,4-butanepolyol di (meth) acrylate, 1,6-hexanepolyol di (meth) acrylate, neope Til glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, 9,9-bis [4- (2-acryloyloxyethoxy) phenyl] fluorene, polyester di (meth) acrylate, Tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, tris (2-hydroxyethyl) isocyanurate di (meth) acrylate, tricyclodecane dimethylol di (meth) acrylate, bis-phenol A EO adduct di (meth) Epoxy (meth) acrylate in which (meth) acrylate is added to diglycidyl ether of acrylate, hydrogenated bisphenol A EO adduct or PO adduct polyol diglycidyl ether , Triethylene glycol divinyl ether, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane EO adduct tri (meth) acrylate, trisacryloyloxyethyl phosphate, pentaerythritol tetra ( (Meth) acrylate, tetrafurfuryl alcohol oligo (meth) acrylate, ethyl carbitol oligo (meth) acrylate, 1,4-butanediol oligo (meth) acrylate, 1,6-hexanediol oligo (meth) acrylate, trimethylolpropane Oligo (meth) acrylate, pentaerythritol oligo (meth) acrylate, (poly) urethane (meth) acrylate, (poly) butadiene (meth) acrylate And the like. These may be used alone or in combination of two or more.

  The component (B) is a polymerization initiator for the component (A). The component (B) is a photopolymerization initiator that cures the component (A) with light such as ultraviolet rays. Among photopolymerization initiators, it is a hydrogen abstraction type photopolymerization initiator. A hydrogen abstraction type photopolymerization initiator is a photopolymerization initiator that generates radicals by extracting hydrogen from other molecules.

  Examples of the hydrogen abstraction type photopolymerization initiator include benzophenones and thioxanthones. These may be used alone or in combination of two or more.

  Examples of the benzophenone compounds include benzophenone, 4-methylbenzophenone, 2,4,6-trimethylbenzophenone, acrylated benzophenone, tetra (t-butylperoxycarbonyl) benzophenone, 4,4′-dimethoxybenzophenone, 4,4 ′. -Diaminobenzophenone, 4-chlorobenzophenone, etc. are mentioned.

  Examples of the thioxanthone compounds include thioxanthone, diethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, and the like.

  Other examples of the hydrogen abstraction type photopolymerization initiator include benzyl, methyl O-benzoylbenzoate, 3-ketocoumarin, 2-ethylanthraquinone, camphorquinone, and Michler's ketone.

  Although content of (B) component is not specifically limited, From viewpoints, such as sclerosis | hardenability of a composition, it is preferable to exist in the range of 0.001-10 mass%. More preferably, it exists in the range of 0.01-10 mass%, More preferably, it exists in the range of 0.01-5 mass%.

  Component (C) is a tertiary amine having a methylene group or methine group bonded to an N atom. The hydrogen abstraction type photopolymerization initiator (B) is a photopolymerization initiator that generates radicals, and the component (A) undergoes radical polymerization. However, when this reaction is carried out in the presence of oxygen, oxygen reacts with the radical of the initiator generated from the component (B), and a peroxy radical of an initiator having low reactivity is generated. Then, the radical polymerization reaction of the component (A) is inhibited. The surface of the coating is a portion that comes into contact with oxygen in the atmosphere, and the radical polymerization reaction of the component (A) is inhibited on the coating surface. If it does so, hardening will become inadequate in the film surface.

  However, since the tertiary amine of component (C) has a methylene group or methine group bonded to the N atom, the hydrogen atom of the methylene group or methine group is extracted by irradiation with light such as ultraviolet rays. Thereby, the radical of the tertiary amine of the (C) component is also generated. That is, at the time of light irradiation, radicals of the initiator of the component (B) are generated and radicals of the tertiary amine of the component (C) are also generated. When oxygen reacts with the radical of the tertiary amine of the component (C), a peroxy radical of the tertiary amine of the component (C) is generated. The methylene group or methine of the tertiary amine of the component (C) Since the hydrogen atom of the group is very easily extracted, it is extracted by the peroxy radical of the tertiary amine of the component (C) or the peroxy radical of the initiator, and the tertiary amine of the highly reactive (C) component. Radicals are generated, thereby promoting the polymerization reaction. Thus, it is presumed that the reaction on the surface of the coating is difficult to be inhibited even under the atmosphere and the resin on the surface of the coating can be sufficiently cured.

  The component (C) is not particularly limited as long as it is a tertiary amine having a methylene group or methine group bonded to the N atom, but a tertiary compound having a methylene group or methine group bonded to the N atom. Alkylamine is preferred. Specific examples of the component (C) include dimethyloctylamine.

  The content of the component (C) is preferably 0.5 parts by mass or more with respect to 100 parts by mass of (A) from the viewpoint of excellent effects of suppressing reaction inhibition. In addition, for example, from the viewpoint of maintaining adhesion and adhesion to a metal such as a terminal fitting or a wire conductor by the component (A), the content of the component (C) is 6 masses per 100 parts by mass of (A). Part or less. (A) By maintaining adhesion and adhesion to metal such as terminal fittings and electric wire conductors by the component, the deterioration of the adhesion to the adherend is suppressed and the anticorrosion performance as an anticorrosion agent is fully exhibited. be able to.

  In addition, the photocurable composition which concerns on this invention may contain the additive in the range which does not inhibit this invention.

  The photocurable composition according to the present invention can be effectively used in applications for suppressing the influence of polymerization inhibition by oxygen. And the photocurable composition which concerns on this invention can be used suitably as a corrosion inhibitor of a covered electric wire with a terminal.

  Below, the covered electric wire with a terminal concerning the present invention is explained in detail.

  FIG. 1 is an external perspective view showing an example of a coated electric wire with a terminal according to the present invention, and FIG. 2 is a longitudinal sectional view taken along line AA in FIG. As shown in FIG. 1 and FIG. 2, the covered electric wire 1 with a terminal of the present invention includes an electric conductor 3 of a covered electric wire 2 in which an electric conductor 3 is covered with an insulating coating (insulator) 4 and a terminal fitting 5. 6 is electrically connected.

  The terminal fitting 5 includes a tab-like connection portion 51 made of an elongated flat plate connected to a counterpart terminal, a wire barrel 52 extending at the end of the connection portion 51, and an electric wire fixing portion made of an insulation barrel 53. 54.

  In the electrical connection portion 6, the insulation coating 4 at the end of the covered electric wire 2 is peeled off to expose the electric wire conductor 3, and the exposed electric wire conductor 3 is pressure-bonded to one side of the terminal fitting 5, thereby covering the electric wire 2. And the terminal fitting 5 are connected. The wire barrel 52 of the terminal fitting 5 is crimped from above the wire conductor 3 of the covered electric wire 2 so that the wire conductor 3 and the terminal fitting 5 are electrically connected. Further, the insulation barrel 53 of the terminal fitting 5 is crimped from above the insulating coating 4 of the covered electric wire 2.

  In the covered electric wire 1 with a terminal, a range indicated by a one-dot chain line is covered with an anticorrosive 7. In addition, the electrical connection part 6 of FIG. 1 is shown in a state where the anticorrosive 7 is seen through. The anticorrosive 7 prevents the metal portion from corroding due to salt water entering from the outside into the contact portion of the wire conductor 3 exposed from the insulating coating 4, the portion of the terminal fitting 5 that is in contact with the exposed wire conductor 3, and the contact portion. To prevent.

  The anticorrosive 7 is made of a cured product of the photocurable composition according to the present invention. In the cured product of the photocurable composition according to the present invention, the resin on the surface is sufficiently cured. For this reason, the problem that the coating surface (surface of the anticorrosive 7) adheres to the inner surface of the connector housing when the terminal fitting 5 of the coated electric wire with terminal 1 is inserted into the connector housing does not occur. Even if the terminal fitting 5 of the covered electric wire 1 is pulled out from the connector housing, the anticorrosive 7 is not likely to be peeled off from the electric conductor 3 and the electrical connection portion 6 of the terminal fitting 5. Thereby, an anticorrosion function can be maintained.

  In the axial direction of the coated electric wire 1 with a terminal, the anticorrosive 7 is insulated from the surface of the terminal fitting 5 ahead of the tip of the electric wire conductor 3 exposed from the insulating coating 4 and after the electric wire conductor 3 exposed from the insulating coating 4. The range up to the surface of the insulating coating 4 further after the insulation barrel 53 that caulks the surface of the coating 4 is continuously covered. That is, the tip 2 a side of the covered wire 2 is covered with the anticorrosive 7 so as to protrude from the tip of the wire conductor 3 to the connection portion 51 side of the terminal fitting 5. The rear end 5 a side of the terminal fitting 5 is covered with an anticorrosive 7 so as to protrude from the end of the insulation barrel 53 to the insulating coating 4 side of the covered electric wire 2. And about the circumferential direction of the covered electric wire 1 with a terminal, the anticorrosive 7 covers continuously the range including the surface of the wire barrel 52 and the insulation barrel 53 from the one side surface 5b of the terminal metal fitting 5 to the other side surface 5b. Yes. Further, the surface of the insulating coating 4 adjacent to the end portion on the rear end 5a side of the insulation barrel 53 is covered with the anticorrosive 7 over the entire circumference, and the end surface on the rear end 5a side of the terminal fitting 5 is not exposed. Yes. In addition, the back surface 5c of the terminal metal fitting 5 may not be covered with the anticorrosive agent 7, and may be covered.

  The peripheral edge of the anticorrosive 7 is composed of a portion (three sides) that contacts the surface of the terminal fitting 5 and a portion (one side) that contacts the surface of the insulating coating 4. Most of the peripheral edge of the anticorrosive 7 is in contact with the surface of the terminal fitting 5. Of the peripheral edge of the anticorrosive 7, all the portions that come into contact with the metal are portions that come into contact with the surface of the terminal fitting 5. The salt water entering through the peripheral edge of the anticorrosive 7 passes between the surface of the terminal fitting 5 and the anticorrosive 7 or between the surface of the insulating coating 4 and the anticorrosive 7.

  It is preferable that the anticorrosive 7 is excellent in adhesiveness with the terminal fitting 5. Therefore, it is preferable that the anticorrosive agent 7 has a superposition tensile shear strength of a copper plate and an acrylic plate measured in accordance with JIS K6850 of 0.5 MPa or more. More preferably, it is 1.0 MPa or more, More preferably, it is 1.5 MPa or more. Note that JIS K6850 (“Adhesive—Test Method for Tensile Shear Adhesive Strength of Rigid Adherents”) uses a standard test piece and is an adhesive bonded product between rigid adherends under specified adjustment and test conditions. Defines the method of measuring the tensile tensile shear strength of In the present application, a test piece is prepared using a copper plate and an acrylic plate as the rigid adherend and using the anticorrosive 7 as an adhesive layer sandwiched between the copper plate and the acrylic plate.

  It is preferable to apply the anticorrosive 7 so that the thickness of the coating after application is in the range of 0.01 to 0.1 mm. If the thickness of the anticorrosive 7 becomes too thick, it may be difficult to insert the terminal fitting 5 into the connector. Moreover, when the thickness of the anticorrosive 7 becomes too thin, there exists a possibility that anticorrosion performance may become inadequate.

  Application | coating of the anticorrosive 7 can use well-known means, such as a dripping method, the apply | coating method, and the extrusion method. Further, when the anticorrosive agent 7 is applied, the temperature of the anticorrosive agent 7 may be adjusted by heating, cooling, or the like. Moreover, in order to improve the permeability (coating property) of the anticorrosive agent 7, when applying, the anticorrosive agent 7 may be diluted with a solvent to form a liquid.

  Hereinafter, each part of the covered electric wire 1 with a terminal is demonstrated.

  The electric wire conductor 3 of the covered electric wire 2 is made of a stranded wire formed by twisting a plurality of strands 3a. In this case, the stranded wire may be composed of one type of metal strand or may be composed of two or more types of metal strand. Moreover, the twisted wire may contain the strand etc. which consist of organic fibers other than a metal strand. Note that “consisting of one type of metal strand” means that all the metal strands constituting the stranded wire are made of the same metal material, and “consisting of two or more types of metal strands” This means that the wire contains metal wires made of different metal materials. The stranded wire may include a reinforcing wire (tension member) for reinforcing the covered electric wire.

  Examples of the material of the metal wire constituting the wire conductor 3 include copper, a copper alloy, aluminum, an aluminum alloy, or a material obtained by applying various platings to these materials. Examples of the material of the metal strand as the reinforcing wire include copper alloy, titanium, tungsten, and stainless steel. Examples of the organic fiber as the reinforcing wire include Kevlar.

  Examples of the material of the insulator 4 include rubber, polyolefin, PVC, and thermoplastic elastomer. These may be used alone or in combination of two or more. Various additives may be appropriately added to the material of the insulator 4. Examples of the additive include a flame retardant, a filler, a colorant and the like.

  The terminal fitting 5 can be formed (processed) into a predetermined shape by pressing a metal plate. Examples of the material (material for the base material) of the terminal fitting 5 include various copper alloys and copper in addition to brass that is generally used. A part (for example, a contact) or the entire surface of the terminal fitting 5 may be plated with various metals such as tin, nickel, and gold.

  As a combination of the terminal fitting 5 and the electric wire conductor 3, it is preferable from the viewpoint of connection reliability that the base metal of the terminal fitting 5 is made of copper or a copper alloy and the electric wire conductor 3 is made of aluminum or an aluminum alloy. In this case, these electrical connection portions 6 are different metal contact portions.

  In addition, in the covered electric wire 1 with a terminal shown in FIG. 1, the terminal metal fitting is crimped and connected to the end of the electric wire conductor, but other known electrical connection methods such as welding may be used instead of the crimping connection.

  In addition, if the airtightness and watertightness with the insulating coating 4 by the insulation barrel 53 are sufficiently secured, the range covered with the anticorrosive 7 is such that the rear end 5a side of the terminal fitting 5 is the insulation barrel 53 side. It may be up to. In this case, all the peripheral ends of the anticorrosive 7 are in contact with the surface of the terminal fitting 5.

  Examples of the present invention and comparative examples are shown below. In addition, this invention is not limited by these Examples.

(Test material)
Isobornyl acrylate: “Light acrylate IB-XA” manufactured by Kyoei Chemical Co., Ltd.
・ Lauryl acrylate: Kyoei Chemical Co., Ltd. “Light acrylate LA”
Thioxanthone photoinitiator: 2-isopropylthioxanthone Benzophenone photoinitiator: 4-methylbenzophenone Tertiary amine: “Farmin O” (dimethyloctylamine) manufactured by Kao Corporation

(Examples 1-4, Comparative Example 2)
A photocurable composition is prepared by mixing a (meth) acrylate monomer, a thioxanthone photoinitiator as a hydrogen abstraction type photopolymerization initiator, and a specific tertiary amine so as to have the composition shown in Table 1. did.

(Comparative Example 1)
A photocurable composition was prepared in the same manner as in Examples 1 to 4, except that no specific tertiary amine was added.

(Examples 5-8, Comparative Example 4)
A photocurable composition was prepared by mixing a (meth) acrylate monomer, a benzophenone photoinitiator as a hydrogen abstraction type photopolymerization initiator, and a specific tertiary amine so as to have the composition shown in Table 1. did.

(Comparative Example 3)
A photocurable composition was prepared in the same manner as in Examples 5 to 8 except that a specific tertiary amine was not blended.

(Measurement of adhesive strength to connector)
As shown in FIG. 3A, a photocurable composition was applied to the end of a 25 mm × 100 mm × 2 mmt polybutylene terephthalate (PBT) sheet 21 so as to be 25 mm × 12.5 mm × 1 mmt. Curing was performed by irradiating cm ² UV light (mercury xenon lamp). At this time, it was cured so that the surface of the cured coating became flat. Thereby, the cured film 22 was formed. A PBT sheet 23 having the same dimensions as the PBT sheet 21 is stacked on the cured coating 22 as shown in FIG. 3B, and a load of 50 g from above is applied to the portion where the surface of the cured coating 22 and the PBT sheet 23 are in contact with each other. And left at 120 ° C. for 120 hours. After removing the load and cooling to room temperature, the PBT sheet 21 and the PBT sheet 23 were pulled in opposite directions, a shear adhesion test was performed, and the adhesive strength was measured. The tensile speed was 1 mm / min. PBT is a material often used as a material for connector housings. Even if the anticorrosive applied to the electrical connection between the terminal fitting and the wire conductor sticks to the connector housing, the anticorrosive does not peel off from the electrical connection and the terminals are removed from the connector housing. As a guideline for extracting the terminal metal fitting of the attached coated electric wire, the adhesive strength was determined to be 0.1 MPa or less.

(Measurement of adhesive strength to terminal fittings)
In accordance with JIS K6850, the overlapping tensile shear strength of the adhesive bonded product between the rigid adherends was measured. A copper plate was used for one rigid adherend and an acrylic plate was used for the other rigid adherend. As shown in FIG. 3B, a photocurable composition is arranged between the copper plate 21 and the acrylic plate 23, and 3 J / cm ² of UV light (mercury xenon lamp) is irradiated from above the acrylic plate 23. Then, the photocurable composition was cured. Thereafter, the copper plate 21 and the acrylic plate 23 were pulled in opposite directions, a shear adhesion test was performed, and the adhesive strength was measured. The tensile speed was 1 mm / min.

(Evaluation of anticorrosion performance)
As shown in FIG. 4, a Sn-plated copper plate 11 of 25 mm × 25 mm × 0.64 mmt was prepared, and aluminum was vapor-deposited in the range of 10 mm × 10 mm in the center of the surface of the copper plate 11 to form a vapor deposition film 12 made of aluminum. An anticorrosive agent was applied to the surface of the copper plate 11 on which the vapor deposition film 12 and the vapor deposition film 12 were formed so as to cover the vapor deposition film 12 to form a film 13 (film thickness 50 μm). Five samples were prepared for each anticorrosive. About the produced sample, the salt spray test was implemented for 96 hours based on JISC0023. In all of the five samples, the case where the aluminum of the vapor deposition film 12 was not discolored was judged as acceptable “◯”, and the case where even one of the samples was discolored in the aluminum of the vapor deposition film 12 was regarded as unacceptable “x”. In addition, the discoloration of aluminum was examined visually.

  In Comparative Examples 1 and 3 in which no specific tertiary amine is blended, it can be seen that the adhesive strength between the cured coating 22 and the PBT sheet 23 is high, and the curing of the surface of the cured coating 22 is insufficient. And in the comparative examples 2 and 4, it turns out that the adhesive strength of the cured film 22 and the copper plate 21 is low, and it is inferior to anticorrosion performance. On the other hand, in Examples 1-4 and 5-8, it turns out that the adhesive strength of the cured film 22 and the PBT sheet 23 is low, and hardening of the surface of the cured film 22 is enough. Moreover, in Examples 1-4 and 5-8, the adhesive strength of the cured film 22 and the copper plate 21 is high, and it turns out that the outstanding anticorrosion function is maintained. And according to the salt spray test, it has confirmed that it was excellent in anticorrosion performance in these Examples.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention.

1 Coated electric wire with terminal 2 Coated electric wire 3 Electric wire conductor 4 Insulation coating (insulator)
5 Terminal fitting 6 Electrical connection 7 Anticorrosive

Claims (6)

Light containing the following components (A) to (C), and having a cured product obtained by measuring the overlap tensile shear strength of a copper plate and an acrylic plate in accordance with JIS K6850 of 0.5 MPa or more. Curable composition.
(A) (Meth) acrylic monomer and / or (meth) acrylic oligomer (B) Hydrogen abstraction type photopolymerization initiator (C) Tertiary amine having methylene group or methine group bonded to N atom   The photocurable composition according to claim 1, wherein the component (B) is a benzophenone or a thioxanthone.   The photocurable composition according to claim 1 or 2, wherein the component (C) is a tertiary alkylamine having a methylene group or a methine group bonded to an N atom.   The content of the component (C) is in the range of 0.5 to 6 parts by mass with respect to 100 parts by mass of the (A), according to any one of claims 1 to 3. Photocurable composition.   The cured product of the photocurable composition according to any one of claims 1 to 4, wherein an electrical connection portion in which the terminal fitting and the wire conductor of the covered electric wire are electrically connected is covered. Covered electric wire with terminal.   6. The base metal of the terminal fitting is made of copper or a copper alloy, the electric wire conductor of the covered electric wire is made of aluminum or an aluminum alloy, and these electrical connection portions are different metal contact portions. Covered electric wire with terminal as described in 2.

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