JP2015185264A - Terminal-provided covered conductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a terminal-provided covered conductor which is excellent in anticorrosion performance even in an environment involving vibration and a cooling/heating cycle.SOLUTION: In a terminal-provided covered conductor, the range from the surface of terminal fitting 5 in the front of the front end of a part exposed from an insulation coating 4 of the wire conductor 3 to the surface of the insulation coating 4 in the back of the back end of a part exposed from the insulation coating 4 of the wire conductor 3, including an electric connection part 6 in which the terminal fitting 5 is connected electrically with the wire conductor 3 of a covered conductor 2, is covered with a coat 7 of a resin composition having breaking elongations of 130% or more at -40°C and 200% or more at 25°C, measured by JIS K7113 after leaving standing at 120°C for 168 h in a sheet-molded state.

Description

  The present invention relates to a covered electric wire with a terminal, and more particularly to a covered electric wire with a terminal excellent in corrosion resistance of an electric connection portion between an electric wire conductor and a terminal fitting.

  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 prevent the ingress of water unless it is densely injected into the connector. If it is injected excessively, it will protrude from the connector and stick the wires and connectors, reducing the handleability. In addition, when the electric wire is bent in the process from manufacture of the wire harness to attachment to the vehicle, a gap is formed between the electric wire coating and the grease, and the waterproofness and the anticorrosion function are impaired.

  Furthermore, vibration and a thermal cycle occur in an on-vehicle environment. If the anticorrosive agent used is poor in flexibility, the coating made of the anticorrosive agent causes internal breakage due to vibration or a thermal cycle, and the coating film is cracked. If it does so, salt water will become easy to osmose | permeate into an electrical connection part from the outside, and there exists a possibility of accelerating the corrosion of an electrical connection part. The crack of the film is likely to occur particularly in a low temperature environment.

  The problem to be solved by the present invention is to provide a coated electric wire with a terminal that is excellent in anticorrosion performance even in an environment in which vibration and a thermal cycle occur.

  In order to solve the above-mentioned problems, a covered electric wire with a terminal according to the present invention includes an electrical connection portion in which a terminal fitting and an electric wire conductor of the covered electric wire are electrically connected, and is a part exposed from the insulating coating of the electric wire conductor. A range from the surface of the terminal fitting ahead of the tip to the insulation coating surface after the rear end of the portion exposed from the insulation coating of the wire conductor is covered with a coating of the resin composition to form the coating. The resin composition has a elongation at break measured in accordance with JIS K7113 of 130% or more at −40 ° C. and 200% or more at 25 ° C. after standing for 168 hours at 120 ° C. in the state of being formed into a sheet. Is a summary.

  In this case, the resin composition for forming the coating film further has an elongation at break measured according to JIS K7113 after being left in a state of 120 ° C. for 168 hours in a state of being formed into a sheet shape and in contact with the copper plate, −40 It is preferably 130% or more at 25 ° C. and 210% or more at 25 ° C.

  Moreover, it is preferable that the resin composition forming the coating film further has an equilibrium elastic modulus of 0.30 MPa or less after being formed into a sheet shape and left in contact with a copper plate at 120 ° C. for 168 hours.

  And the other covered electric wire with a terminal concerning the present invention includes the electric connection part where the terminal metal fitting and the electric wire conductor of the covered electric wire were electrically connected, from the tip among the parts exposed from the insulating covering of the electric wire conductor The range from the surface of the previous terminal fitting to the insulating coating surface after the rear end of the portion exposed from the insulating coating of the wire conductor is covered with the resin composition coating, and the resin composition forming the coating The product has a breaking elongation measured in accordance with JIS K7113 at 130 ° C or higher at -40 ° C and 210% or higher at 25 ° C after being left in the form of a sheet and in contact with a copper plate for 168 hours. This is the gist.

  Moreover, the other covered electric wire with a terminal according to the present invention includes an electrical connection portion in which the terminal fitting and the electric wire conductor of the covered electric wire are electrically connected, and the tip of the portion exposed from the insulating coating of the electric wire conductor A resin from which the range from the surface of the earlier terminal fitting to the insulating coating surface after the rear end of the portion exposed from the insulating coating of the wire conductor is covered with the coating of the resin composition, and forms the coating The gist of the composition is that the equilibrium elastic modulus after being left in a state of 120 ° C. for 168 hours in the state of being formed into a sheet and in contact with a copper plate is 0.30 MPa or less.

  The resin composition constituting the coating film further has an elongation at break measured in accordance with JIS K7113 at an early stage before receiving a thermal history in a state of being formed into a sheet shape at 130% or more at -40 ° C. It is preferably 200% or more at 25 ° C.

  Moreover, it is preferable that the resin composition which comprises the said film contains curable resin, the said film consists of hardened | cured material, and the value of the said elongation at break or the value of the said equilibrium elastic modulus is a value after hardening. At this time, the curable resin is preferably a photocurable resin. And it is preferable that the viscosity in 25 degreeC measured based on JISZ8803 of the resin composition containing the said curable resin exists in the range of 1000-10000 mPa * s.

  And it is preferable that the base material of the said terminal metal fitting is comprised with copper or a copper alloy, the base material of the said electric wire conductor is comprised with aluminum or the aluminum alloy, and the said electrical-connection part is a dissimilar metal contact part.

  According to the coated electric wire with a terminal according to the present invention, a predetermined range including the electrical connection portion where the terminal fitting and the electric wire conductor of the coated electric wire are electrically connected is covered with the coating of the resin composition. The elongation at break measured according to JIS K7113 after standing for 168 hours at 120 ° C. in the state of forming a resin composition in a sheet form is 130% or more at −40 ° C. and 200% or more at 25 ° C. As a result, even in an environment where vibration and a thermal cycle occur, the coating is unlikely to crack, and the coating's anticorrosion function of suppressing the ingress of salt water into the electrical connection portion can be maintained, and the anticorrosion performance is excellent.

  In this case, the resin composition for forming a film has a breaking elongation measured according to JIS K7113 after being left to stand at 120 ° C. for 168 hours in a state where the resin composition is further formed into a sheet shape and in contact with the copper plate. In an environment where vibration and a thermal cycle occur even when copper and the coating that generate copper ions that cause deterioration of the coating made of the resin composition are 130% or more at 25 ° C. and 210% or more at 25 ° C. Thus, the coating is unlikely to crack, and the anticorrosion function of the coating that suppresses the infiltration of salt water into the electrical connection portion can be maintained, and the anticorrosion performance is excellent.

Further, when the resin composition for forming the coating film is further formed into a sheet shape and left in contact with the copper plate at 120 ° C. for 168 hours, the equilibrium elastic modulus is 0.30 MPa or less, vibration or cooling / heating cycle Even in an environment in which the film is formed, the film is hardly cracked, and the anticorrosion function of the film that suppresses the intrusion of salt water into the electrical connection portion can be maintained, and the anticorrosion performance is excellent.

  And according to the other covered electric wire with a terminal concerning the present invention, the predetermined range including the electric connection part in which the terminal metal fitting and the electric wire conductor of the covered electric wire are electrically connected is covered with the coating of the resin composition. The elongation at break measured according to JIS K7113 after the resin composition forming the coating film was formed into a sheet shape and in contact with the copper plate at 120 ° C. for 168 hours was 130 at −40 ° C. % Or more, and 210% or more at 25 ° C. Even in the case where the copper and the film that generate copper ions that cause deterioration of the film made of the resin composition come into contact with each other, in an environment where vibration and a thermal cycle occur, The coating is less prone to cracking, can maintain the coating's anticorrosive function of suppressing the ingress of salt water into the electrical connection, and has excellent anticorrosion performance.

  According to still another covered electric wire with a terminal according to the present invention, a predetermined range including an electrical connection portion where the terminal fitting and the electric wire conductor of the covered electric wire are electrically connected is covered with the coating of the resin composition. Since the equilibrium elastic modulus after the resin composition forming the coating film is formed into a sheet shape and left in contact with the copper plate at 120 ° C. for 168 hours is 0.30 MPa or less, vibration and cooling Even in an environment where cycling occurs, the coating is unlikely to crack, and the coating's anticorrosion function of suppressing the ingress of salt water into the electrical connection portion can be maintained, resulting in excellent anticorrosion performance.

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.

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

  The covered electric wire with a terminal according to the present invention includes an electric connection portion in which the terminal fitting and the electric wire conductor of the covered electric wire are electrically connected, and the surface of the terminal fitting ahead of the tip of the portion exposed from the insulating coating of the electric wire conductor To the insulation coating surface after the rear end of the portion exposed from the insulation coating of the wire conductor is covered with a coating of the resin composition, and the resin composition forming the coating is a specific resin It consists of a composition.

  The resin composition for forming the coating film according to the first embodiment has an elongation at break measured in accordance with JIS K7113 of 130 at −40 ° C. after standing for 168 hours at 120 ° C. in the state of being formed into a sheet. % Or more and 200% or more at 25 ° C. Thus, even after thermal aging, the elongation at break at extremely low temperatures (−40 ° C.) and room temperature (25 ° C.) is maintained at a high level. Cracks are less likely to occur. Thereby, the anticorrosion function of the film which suppresses the infiltration of salt water into the electrical connection portion can be maintained, and the anticorrosion performance is excellent.

  The elongation at break after heat aging needs to be kept high not only at extremely low temperatures (−40 ° C.) but also at room temperature (25 ° C.). In addition to room temperature (25 ° C.), it is necessary to maintain a high temperature not only at an extremely low temperature (−40 ° C.). If any one of them is not satisfied, the coating film is easily cracked, and the anticorrosion function of the coating film that suppresses the intrusion of salt water into the electrical connection portion is lowered.

  At extremely low temperatures (−40 ° C.), the elongation at break after heat aging is preferably 140% or more. More preferably, it is 150% or more. Further, at room temperature (25 ° C.), the elongation at break after heat aging is preferably 300% or more. More preferably, it is 400% or more.

  The elongation at break after heat aging is preferably maintained high not only at extremely low temperatures (−40 ° C.) and room temperature (25 ° C.) but also at low temperatures (0 ° C.). Specifically, it is preferably 200% or more at a low temperature (0 ° C.). More preferably, it is 250% or more, More preferably, it is 300% or more.

  When the elongation at break after heat aging is 140% or more at extremely low temperature (−40 ° C.), 300% or more at room temperature (25 ° C.), and 250% or more at low temperature (0 ° C.), the cracking of the coating is particularly suppressed. The anticorrosion function of the coating that suppresses the penetration of salt water into the electrical connection portion is particularly excellent.

  The resin composition for forming the coating film according to the first embodiment is further obtained by breaking elongation measured in accordance with JIS K7113 after being formed into a sheet and left in contact with a copper plate at 120 ° C. for 168 hours. However, it is preferably 130% or more at -40 ° C and 210% or more at 25 ° C. As described above, the high elongation at break even at a low temperature (−40 ° C.) and at room temperature (25 ° C.) is maintained even after heat aging in contact with the copper plate, thereby deteriorating the film made of the resin composition. Even when copper and the film that generate copper ions come into contact with each other, the film has an anticorrosive function that prevents the film from cracking and prevents salt water from entering the electrical connections in an environment where vibration and cooling cycles occur. Can be maintained. When copper or a copper alloy is used as the material for the wire conductor or terminal fitting, the copper and the coating come into contact with each other.

  At an extremely low temperature (−40 ° C.), the elongation at break after thermal aging in a state of contact with a copper plate is preferably 140% or more. More preferably, it is 150% or more. Moreover, at room temperature (25 ° C.), the elongation at break after thermal aging in a state of contact with the copper plate is preferably 250% or more. More preferably, it is 300% or more.

  The elongation at break after thermal aging in contact with the copper plate is preferably maintained high not only at a very low temperature (−40 ° C.) and room temperature (25 ° C.) but also at a low temperature (0 ° C.). Specifically, it is preferably 200% or more at a low temperature (0 ° C.). More preferably, it is 250% or more, More preferably, it is 300% or more.

  The elongation at break after thermal aging in contact with the copper plate is 140% or higher at extremely low temperature (−40 ° C.), 250% or higher at room temperature (25 ° C.), and 200% or higher at low temperature (0 ° C.). The cracking of the film is particularly easily suppressed, and the anticorrosion function of the film, which suppresses the intrusion of salt water into the electrical connection portion, is particularly excellent.

  The resin composition for forming the coating film according to the first embodiment further has an equilibrium elastic modulus of 0.30 MPa or less after being formed into a sheet and left in contact with a copper plate at 120 ° C. for 168 hours. It is preferable. More preferably, it is 0.25 MPa or less. The equilibrium elastic modulus can be calculated from the measurement result of the storage elastic modulus in dynamic viscoelasticity. The storage elastic modulus can be measured using a resin composition formed into a sheet having a predetermined thickness. Using a dynamic viscoelasticity measuring device, the storage elastic modulus is measured while changing the temperature within a predetermined range. From the relationship between storage elastic modulus and temperature, the equilibrium elastic modulus in the equilibrium state is obtained. The storage elastic modulus is an index representing the elastic property of the material, and the storage elastic modulus component is caused by the cross-linking point in the rubber-like elastic region. The equilibrium elastic modulus, which is the storage elastic modulus component of the rubber-like elastic region, is related to the crosslink density of the material.

  When the equilibrium elastic modulus, which is an index of the crosslinking density, is 0.30 MPa or less, the number of crosslinking points is relatively large, and thus the heat resistance is excellent. In other words, because it is excellent in heat aging characteristics, even in an environment where vibrations and cooling cycles occur, it is difficult for the coating to crack, and the anticorrosion function of the coating can be maintained, which suppresses the ingress of salt water into the electrical connection part, Excellent anticorrosion performance. When the equilibrium elastic modulus is 0.25 MPa or less, the cracking of the film is particularly easily suppressed, and the anticorrosion function of the film is particularly excellent in that it prevents salt water from entering the electrical connection portion. On the other hand, the lower limit value of the equilibrium elastic modulus is not particularly limited from the viewpoint of excellent heat aging characteristics, but from the viewpoint of anticorrosion performance, the equilibrium elastic modulus is preferably 0.15 MPa or more.

  According to the first embodiment, the resin composition for forming the coating film further has an elongation at break measured in accordance with JIS K7113 at an initial stage before receiving a thermal history in a state of being formed into a sheet shape at −40 ° C. It is preferably 130% or more at 25 ° C. and 200% or more at 25 ° C. If it does so, it is excellent in the elongation at break after heat aging.

  At an extremely low temperature (−40 ° C.), the initial breaking elongation is more preferably 200% or more. More preferably, it is 240% or more. Further, at room temperature (25 ° C.), the initial elongation at break is preferably 300% or more. More preferably, it is 400% or more.

  The initial elongation at break is preferably maintained high not only at very low temperatures (−40 ° C.) and room temperature (25 ° C.) but also at low temperatures (0 ° C.). Specifically, it is preferably 200% or more at a low temperature (0 ° C.). More preferably, it is 250% or more, More preferably, it is 300% or more.

  When the initial elongation at break is 200% or more at extremely low temperature (−40 ° C.), 400% or more at room temperature (25 ° C.), and 300% or more at low temperature (0 ° C.), the elongation at break after heat aging is particularly excellent. .

  The resin composition for forming the coating film according to the second embodiment has an elongation at break measured according to JIS K7113 after being left in a state of 120 ° C. for 168 hours in a state of being formed into a sheet shape and in contact with a copper plate. It is 130% or more at -40 ° C and 210% or more at 25 ° C. As described above, the high elongation at break at extremely low temperatures (−40 ° C.) and room temperature (25 ° C.) after thermal aging in contact with the copper plate causes the deterioration of the coating film made of the resin composition. When the copper and the film that generate copper ions come into contact with each other, the film is less susceptible to cracking in an environment where vibration and cooling cycles occur, and the anticorrosive function of the film is maintained to prevent salt water from entering the electrical connections. can do.

  In the resin composition for forming the film according to the second embodiment, a preferable value as the elongation at break after thermal aging in a state of contact with the copper plate is the resin composition for forming the film according to the first embodiment. In a product, it is the same as the preferable value described as the elongation at break after thermal aging in a state of contact with a copper plate.

  Similarly to the resin composition forming the coating film according to the first embodiment, the resin composition forming the coating film according to the second embodiment is further formed into a sheet shape and brought into contact with a copper plate. It is preferable that the equilibrium elastic modulus after standing at 168 ° C. for 168 hours is 0.30 MPa or less. More preferably, it is 0.25 MPa or less. Furthermore, the elongation at break measured in accordance with JIS K7113 at the initial stage before receiving the thermal history in the state of being formed into a sheet shape is 130% or more at −40 ° C. and 200% or more at 25 ° C. preferable. Moreover, the value preferable as an initial breaking elongation is the same as the preferable value described as an initial breaking elongation in the resin composition which forms the said film based on 1st embodiment.

  The resin composition for forming the coating film according to the third embodiment has an equilibrium elastic modulus of 0.30 MPa or less after being formed into a sheet and left in contact with a copper plate at 120 ° C. for 168 hours. More preferably, it is 0.25 MPa or less. When the equilibrium elastic modulus, which is an index of the crosslinking density, is 0.30 MPa or less, the number of crosslinking points is relatively large, and thus the heat resistance is excellent. In other words, because it is excellent in heat aging characteristics, even in an environment where vibrations and cooling cycles occur, it is difficult for the coating to crack, and the anticorrosion function of the coating can be maintained, which suppresses the ingress of salt water into the electrical connection part, Excellent anticorrosion performance. When the equilibrium elastic modulus is 0.25 MPa or less, the cracking of the film is particularly easily suppressed, and the anticorrosion function of the film is particularly excellent in that it prevents salt water from entering the electrical connection portion. On the other hand, the upper limit of the equilibrium elastic modulus is not particularly limited from the viewpoint of excellent heat aging characteristics, but from the viewpoint of anticorrosion performance, the equilibrium elastic modulus is preferably 0.15 MPa or more.

  In the present invention, the resin composition for forming the coating film has desired characteristics depending on the type / structure / molecular weight of the resin, the type / blending amount of the polymerization initiator, the type / blending amount of the crosslinking agent, and the addition of additives. It can have.

  The resin contained in the resin composition for forming the film is not particularly limited as long as the resin composition has a specific physical property value, but it has excellent heat resistance. Therefore, the resin composition constituting the coating film preferably contains a curable resin. In this case, the film becomes a cured product. When the film is a cured product, the value of elongation at break and the value of equilibrium elastic modulus are values after curing. Examples of the curable resin include a photocurable resin that is cured by irradiation with light such as ultraviolet rays, a thermosetting resin, and a moisture curable resin. Among these, a photocurable resin is preferable from the viewpoint of excellent curing speed. In the resin composition containing a curable resin, a polymerization initiator may be added. Examples of the polymerization initiator include a photopolymerization initiator and a thermal polymerization initiator.

  In the resin composition containing the curable resin, a component having excellent flexibility can be blended from the viewpoint of improving the elongation at break. Examples of such components include thermoplastic elastomers, rubbers, plasticizers, and the like.

  The resin composition forming the coating is preferably liquid at 25 ° C. from the viewpoint of excellent workability. Moreover, it is preferable that the viscosity in 25 degreeC measured based on JISZ8803 is in the range of 1000-10000 mPa * s. In this case, the resin composition can be adjusted to a liquid state using a solvent, but from the viewpoint of not using a solvent, the curable resin (before curing) contained in the resin composition for forming the film is used. Is preferably liquid at 25 ° C. Moreover, it is preferable that the viscosity in 25 degreeC measured based on JISZ8803 is in the range of 1000-10000 mPa * s.

  Examples of the photocurable resin include (meth) acrylic resins. The (meth) acrylic monomer of the (meth) acrylic resin 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.

  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.

  The photopolymerization initiator is not particularly limited as long as it is a compound that absorbs ultraviolet rays to initiate radical polymerization, and a conventionally known photopolymerization initiator can be used. Specifically, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-2-phenylacetophenone, xanthone, fluorenone, benzaldehyde, fluorene, anthraquinone, ethylanthraquinone, triphenylamine, carbazole, 3-methylacetophenone, 4-chloro Benzophenone, 4,4′-dimethoxybenzophenone, 4,4′-diaminobenzophenone, Michler's ketone, benzoin propyl ether, benzoin ethyl ether, benzyl dimethyl ketal, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropane- 1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, thioxanthone, diethylthioxanthone, 2-isopropylthioxanthone, 2-c Rothioxanthone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis- (2,6-dimethoxybenzoyl) ) -2,4,4-trimethylpentylphosphine oxide. These may be used alone or in combination of two or more.

  As thermal polymerization initiators, azoisobutyl nitrile (AIBN), benzoyl peroxide (BPO), lauroyl peroxide, acetyl peroxide, methyl ethyl ketone peroxide, cumene hydroperoxide, di-tert-butyl peroxide, tert-butyl peroxide Examples thereof include peroxides such as benzoate and cyclohexanone peroxide.

  Although content of a polymerization initiator is not specifically limited, From viewpoints, such as sclerosis | hardenability of a resin 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%.

  The resin composition for forming the film may contain an additive as long as the present invention is not inhibited. Additives include tackifiers, hydroquinone, mercaptans and other stabilizers, molecular weight regulators, viscosity modifiers such as fine silica, leveling agents, antioxidants, metal deactivators, flame retardants, flame retardant aids , Coloring pigments, dyes, dispersants and the like.

  Next, an example of the covered electric wire with a terminal of the present invention will be described with reference to the drawings. 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 terminal-equipped covered electric wire 1 is configured such that the electric wire conductor 3 of the covered electric wire 2 in which the electric wire conductor 3 is covered with the insulating coating (insulator) 4 and the terminal fitting 5 are electrically connected by the electric connection portion 6. 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. The terminal fitting 5 can be formed (processed) into a predetermined shape by pressing a metal plate.

  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 terminal-attached covered electric wire 1, the range indicated by the alternate long and short dash line is covered with the coating 7 of the resin composition. Specifically, among the portions exposed from the insulation coating 4 of the wire conductor 3, the insulation coating 4 after the rear end of the portion exposed from the insulation coating 4 of the wire conductor 3 from the surface of the terminal fitting 5 ahead of the tip. The range up to the surface of is covered with the coating 7. That is, the tip 2 a side of the covered electric wire 2 is covered with the coating 7 so as to slightly protrude from the tip of the electric wire conductor 3 to the connection portion 51 side of the terminal fitting 5. The tip 5 a side of the terminal fitting 5 is covered with the coating 7 so as to protrude slightly from the end of the insulation barrel 53 to the insulating coating 4 side of the covered electric wire 2. As shown in FIG. 2, the side surface 5 b of the terminal fitting 5 is also covered with the coating 7. In addition, the back surface 5c of the terminal metal fitting 5 may not be covered with the film 7, and may be covered. The peripheral end of the coating 7 is composed of a portion that contacts the surface of the terminal fitting 5, a portion that contacts the surface of the wire conductor 3, and a portion that contacts the surface of the insulating coating 4.

  In this manner, the electrical connection portion 6 is covered with the coating 7 with a predetermined thickness along the outer peripheral shape of the terminal fitting 5 and the covered electric wire 2. Thereby, the exposed part of the wire conductor 3 of the covered electric wire 2 is completely covered with the coating 7, so that it is not exposed to the outside. Therefore, the electrical connection 6 is completely covered with the coating 7. Since the coating 7 is excellent in adhesion to any of the electric wire conductor 3, the insulating coating 4, and the terminal fitting 5, moisture or the like enters the electric wire conductor 3 and the electrical connection portion 6 from the outside and the metal portion corrodes by the coating 7. To prevent. Moreover, since it is excellent in adhesiveness, for example, even when an electric wire is bent in the process from manufacture of a wire harness to attachment to a vehicle, the coating 7, the wire conductor 3, the insulation coating 4, and the terminal at the peripheral edge of the coating 7 It is difficult to form a gap between any of the metal fittings 5, and waterproofness and anticorrosion function are maintained.

  The resin composition forming the coating is applied in a predetermined range. Application | coating of the resin composition which forms the said film can use well-known means, such as a dripping method, the apply | coating method, and an extrusion method. When applying the resin composition for forming the film, the temperature may be adjusted by heating, cooling, or the like.

  The resin composition forming the coating is applied in a predetermined range with a predetermined thickness. The thickness is preferably within a range of 0.01 to 0.1 mm. If the resin composition forming the coating becomes too thick, it is difficult to insert the terminal fitting 5 into the connector. When the resin composition forming the coating becomes too thin, the anticorrosion performance tends to be lowered. In order to obtain a predetermined thickness, it is preferable that the viscosity of the resin composition forming the coating film is within a predetermined range at 25 ° C.

  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 2.

  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. As a metal strand which comprises the electric wire conductor 3, from the viewpoint of weight reduction, the material by which various plating was given to aluminum, aluminum alloy, or these materials is preferable.

  Examples of the material for the insulating coating 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 insulating coating 4. Examples of the additive include a flame retardant, a filler, a colorant and the like.

  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.

  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.

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

(1) Production of covered electric wire For 100 parts by mass of polyvinyl chloride (degree of polymerization 1300), 40 parts by mass of diisononyl phthalate as a plasticizer, 20 parts by mass of calcium bicarbonate as a filler, and calcium zinc-based stabilizer 5 as a stabilizer A polyvinyl chloride composition was prepared by mixing parts by mass at 180 ° C. with an open roll and forming the pellets with a pelletizer.

  Next, using a 50 mm extruder, the polyvinyl chloride composition is 0.28 mm thick around a wire conductor (cross-sectional area 0.75 mm) made of an aluminum alloy twisted wire in which seven aluminum alloy wires are twisted together. Extrusion coated. This produced the covered electric wire (PVC electric wire).

(2) Crimp connection of terminal fittings After stripping the end of the produced coated wire and exposing the wire conductor, cover the male terminal fitting (tab width 0.64mm) made of brass, which is widely used for automobiles It crimped and crimped to the end of the electric wire.

(3) Anticorrosion treatment In the case where a terminal metal fitting is crimped to a coated electric wire, an ultraviolet curable resin composition is applied so as to cover the area shown by the one-dot chain line in FIG. 1 including the electrical connection portion between the electric wire conductor and the terminal metal fitting. Then, the exposed wire conductor and terminal barrel were covered. At this time, a certain amount was applied using a pressure dispenser. Thereafter, the applied ultraviolet curable resin composition was irradiated with ultraviolet rays for 30 seconds to cure the ultraviolet curable resin composition, and a coated electric wire with a terminal was produced. The thickness of the coating is 0.05 mm.

(Measurement of initial elongation at break)
A sheet-like cured product (film thickness 200 μm) of the ultraviolet curable resin composition was prepared, No. 2 dumbbell was prepared as a test piece from the sheet-like cured product, and a shear tensile test was performed in accordance with JIS K7113.

(Measurement of elongation at break after thermal aging)
After preparing a sheet-like cured product (film thickness 200 μm) of the ultraviolet curable resin composition and leaving the sheet-like cured product to stand at 120 ° C. for 168 hours, a No. 2 dumbbell was used as a test piece from the heat-aged sheet-like cured product. A shear tensile test was performed in accordance with JIS K7113.

(Measurement of elongation at break after copper contact thermal aging)
A sheet-like cured product (thickness 200 μm) of an ultraviolet curable resin composition is prepared on a copper plate, and the sheet-like cured product is left at 120 ° C. for 168 hours in contact with the copper plate, and then thermally aged. A No. 2 dumbbell was produced as a test piece from the cured product, and a shear tensile test was performed in accordance with JIS K7113.

(Measurement of equilibrium elastic modulus)
A sheet-like cured product (thickness 200 μm) of an ultraviolet curable resin composition is prepared on a copper plate, and the sheet-like cured product is left at 120 ° C. for 168 hours in contact with the copper plate, and then thermally aged. A sample for measurement (30 mm × 3 mm × 0.2 mm) was cut out from the cured product, and using a dynamic viscoelasticity measuring device (DMA), a load strain of 0.05%, a frequency of 1 to 10 Hz, and a temperature range of 150 to 170 ° C. The storage modulus was measured. From the obtained temperature dependence curve of the storage elastic modulus, the equilibrium elastic modulus at which the storage elastic modulus becomes almost constant regardless of the temperature was obtained.

(Evaluation of anticorrosion performance)
A thermal shock test was performed on the coated electric wire with terminal subjected to the anticorrosion treatment, and it was visually observed whether or not the coating was cracked. The case where it was confirmed that the coating was cracked was designated as “NG”. The thermal shock test was conducted 10 times for each material, and the anticorrosion performance was evaluated from the number of individuals in which cracks were confirmed. It can be said that the smaller the number of individuals in which cracking was confirmed, the better the anticorrosion performance in an environment where vibrations and cooling cycles occur. In the thermal shock test, after holding at -40 ° C. for 30 minutes, a thermal shock by a thermal cycle of holding at 85 ° C. for 30 minutes is applied to the coated electric wire with a terminal subjected to anticorrosion treatment, and this is repeated 500 cycles. .

  From Table 1 (Example 1), the elongation at break after thermal aging of the sheet-like cured product of the ultraviolet curable resin composition is 130% or more at −40 ° C. and 200% or more at 25 ° C. It can be seen that cracks are less likely to occur in the coating of the coated electric wire with terminal to which the anti-corrosion is applied, and the anticorrosion performance is excellent even in an environment where vibration and a thermal cycle occur.

  From Table 2 (Example 2), the elongation at break after thermal aging in a state of contact with the copper plate of the sheet-like cured product of the ultraviolet curable resin composition is 130% or more at −40 ° C. and 210% at 25 ° C. By the above, it turns out that it becomes difficult to produce a crack in the film of the coated electric wire with a terminal to which anticorrosion processing was performed, and it is understood that it is excellent in anticorrosion performance also in the environment where a vibration and a thermal cycle occur.

  From Table 3 (Example 3), the anticorrosion treatment is performed when the equilibrium elastic modulus after thermal aging in the state of contact with the copper plate of the sheet-like cured product of the ultraviolet curable resin composition is 0.30 MPa or less. It can be seen that the coating of the coated electric wire with terminal is less likely to be cracked, and is excellent in anticorrosion performance even in an environment where vibration and a thermal cycle occur.

  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 5 Terminal fitting 6 Electrical connection 7 Coating

Claims (10)

From the surface of the terminal fitting ahead of the tip of the portion exposed from the insulation coating of the wire conductor, including the electrical connection portion where the terminal fitting and the wire conductor of the covered wire are electrically connected, from the insulation coating of the wire conductor The range from the rear end to the insulating coating surface after the exposed part is covered with the coating of the resin composition,
The resin composition forming the coating film has a breaking elongation measured in accordance with JIS K7113 after standing at 120 ° C. for 168 hours in the state of being formed into a sheet shape, at 130% or more at −40 ° C., and 200 at 25 ° C. %. A covered electric wire with a terminal characterized by being at least%. From the surface of the terminal fitting ahead of the tip of the portion exposed from the insulation coating of the wire conductor, including the electrical connection portion where the terminal fitting and the wire conductor of the covered wire are electrically connected, from the insulation coating of the wire conductor The range from the rear end to the insulating coating surface after the exposed part is covered with the coating of the resin composition,
The resin composition for forming the coating film has a breaking elongation measured in accordance with JIS K7113 of 130% or more at −40 ° C. after being left in a state of 120 ° C. for 168 hours in a state of being formed into a sheet and in contact with a copper plate. A covered electric wire with a terminal, which is 210% or more at 25 ° C. From the surface of the terminal fitting ahead of the tip of the portion exposed from the insulation coating of the wire conductor, including the electrical connection portion where the terminal fitting and the wire conductor of the covered wire are electrically connected, from the insulation coating of the wire conductor The range from the rear end to the insulating coating surface after the exposed part is covered with the coating of the resin composition,
The resin composition for forming the coating film is a coated electric wire with terminal having an equilibrium elastic modulus of 0.30 MPa or less after being left in a state of 120 ° C. for 168 hours in a state of being formed into a sheet shape and in contact with a copper plate .   The resin composition forming the coating film further has an elongation at break measured in accordance with JIS K7113 of 130 at −40 ° C. after standing for 168 hours at 120 ° C. in a state of being formed into a sheet and in contact with a copper plate. 2 or more and 210% or more at 25 ° C. The covered electric wire with a terminal according to claim 1.   The resin composition for forming the coating film further has an equilibrium elastic modulus of 0.30 MPa or less after being formed into a sheet shape and left in contact with a copper plate at 120 ° C for 168 hours. The covered electric wire with a terminal of 1.   The resin composition constituting the coating film further has an elongation at break measured in accordance with JIS K7113 at an initial stage before receiving a heat history in a state of being formed into a sheet shape at 130% or more at -40 ° C, 25 ° C. It is 200% or more in, The covered electric wire with a terminal of any one of Claim 1 to 5 characterized by the above-mentioned.   The resin composition constituting the coating contains a curable resin, the coating is made of a cured product, and the value of the elongation at break or the value of the equilibrium elastic modulus is a value after curing. The covered electric wire with a terminal according to any one of 1 to 6.   The said curable resin is a photocurable resin, The covered electric wire with a terminal of Claim 7 characterized by the above-mentioned.   The terminal according to claim 7 or 8, wherein a viscosity at 25 ° C of the resin composition containing the curable resin measured in accordance with JIS Z8803 is in a range of 1000 to 10,000 mPa · s. Covered electric wire.   The base material of the terminal fitting is made of copper or copper alloy, the base material of the wire conductor is made of aluminum or an aluminum alloy, and the electrical connection portion is a contact portion between different metals. The covered electric wire with a terminal according to any one of Items 1 to 9.

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