JP2002260452A - Noncombustible multicore flat insulated wire and manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a noncombustible multicore flat insulated wire, which does not lower mountability to an apparatus and is noncombustible without halogen compounds. SOLUTION: This noncombustible multicore flat insulating wire 10 contains no halogen compounds, wherein a covering tape 12 is formed with a molding resin comprising an ethylene-vinylacetate resin of vinylacetate content of 22-30% by weight and magnesium hydroxide added using an extruding mold 13, and then a plurality of conductors 11 arranged in a line with a given interval are put between both covering tapes 12, and furthermore are laminated and pressure- molded through forming rollers 14 to form an insulating covering, and hereafter the insulating covering is crosslinked by γ ray radiation 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin flame-retardant multi-core flat insulated wire used for electrical wiring of electronic and information equipment.

[0002]

2. Description of the Related Art In recent years, development and recycling of environmentally friendly products have been demanded in various fields from the viewpoint of global environmental protection. For this reason, the generation of highly corrosive halogen gas at the time of incineration of electric wire disposal has come to be regarded as a problem of global environmental pollution in the field of electric wires for wiring in equipment. To increase the flame retardancy of insulated wires,
Although the use of halogen compounds is extremely useful, the development of flame-retardant insulated wires that do not contain halogen compounds is underway.

In addition, various electronic and information devices have been reduced in size and weight, and electric wires for these electric wires have been multi-core flattened by thin-walled insulation, thereby saving space and improving wiring workability. Have been However, a flame-retardant insulating resin containing no halogen compound has a low fluidity and is difficult to coat and form, and thus cannot be used for coating a multi-core flat insulated wire.

Although it is possible to improve the coating moldability by increasing the fluidity of the base resin for coating molding,
The addition of compounding agents to enhance flow properties also changes other properties. For example, when the fluidity of the base resin is increased, the adhesiveness of the resin is also increased, and the separation from the molding roller is deteriorated, so that the molding is also difficult. In addition, the elongation, tensile strength, and the like that the base resin originally has may change, thereby deteriorating device mountability such as connection to an electric terminal, or reducing flame retardancy.

Therefore, when forming a multi-core flat insulated wire from a flame-retardant insulating resin containing no halogen compound, the base resin is extruded into a tape shape. Next, a method in which a plurality of conductors are sandwiched from both sides by an extruded tape-shaped molded body, laminated with a molding roller, and pressure molded is conceivable. However, also in this case, in order to form a thin insulating coating, it is necessary to extrude a thin tape, and it is necessary to consider the fluidity of the base resin, the adhesiveness with a forming roller, and the like.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has been made of a flame-retardant multi-core flat insulated wire which does not contain a halogen compound without deteriorating the mountability to equipment. It is an object to provide a manufacturing method thereof.

[0007]

The flame-retardant multi-core flat insulated wire according to the present invention is a flame-retardant multi-core flat insulated wire containing no halogen compound, and the insulating coating is 22 to 30% by weight of acetic acid. It is formed of a molding resin obtained by adding magnesium hydroxide to an ethylene vinyl acetate resin containing vinyl, and is characterized in that it is crosslinked by γ-ray irradiation.

The method for producing a flame-retardant multi-core flat insulated wire according to the present invention is a method for producing a flame-retardant multi-core flat insulated wire containing no halogen compound, comprising 22 to 30% by weight of vinyl acetate. Forming a coating tape by extrusion molding of a molding resin obtained by adding magnesium hydroxide to ethylene vinyl acetate resin containing, followed by forming a plurality of conductors arranged in a row at a predetermined interval by sandwiching the conductor with the coating tape from both sides It is characterized by laminating with a roller and press-molding to form an insulating coating, and thereafter cross-linking the insulating coating by γ-ray irradiation.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a view schematically showing a method for manufacturing a multi-core flat insulated wire. 10 is a multi-core flat insulated wire, 11 is a conductor, 12 is a covering tape, 13 is a T-die, 14 is a forming roller, and 15 is irradiation-crosslinking. The device is shown. The conductor 11 is a single wire obtained by applying tin plating or the like to a soft copper or aluminum wire, or a stranded wire obtained by twisting a plurality of thin single wires. Covering tape 1
2 is continuously formed in an uncured tape shape by extrusion molding of the T-die 13 using the molding resin according to the present invention.

[0010] The plurality of conductors 11 are arranged in a line at a predetermined pitch and are transported in the direction of the arrow.
The plurality of conductors 11 arranged in a row are transported to the forming roller 14 so as to sandwich both surfaces thereof. The covering tape 12
It is pressed by the forming roller 14, laminated integrally with the conductor 11 therebetween, and formed into a predetermined shape.

FIG. 2 schematically shows the forming roller 14 and a coating forming state. The forming roller 14 is composed of a pair of rollers for pressing both sides of the covering tape 12, and has irregularities 14 a for forming into a predetermined shape on its outer peripheral surface. The forming surface of the forming roller 14 has been subjected to a surface treatment such as fluororesin coating so that the forming surface does not adhere to the covering tape 12. Further, the forming roller 14 is provided with means for heating or cooling as required. Due to the forming roller 14, the conductor 11 is coated on both sides with the covering tape 12.
Are laminated by bonding or fusion to be integrated by the common coating 12a to form the multi-core flat insulated wire 10a.

A specific example of the present invention is a multi-core flat insulated wire having a thickness of about 1 mm and a coating thickness of 0.2 m.
m. The coating thickness t of the coating 12a may be as thin as possible as long as a predetermined electrical insulation resistance and withstand voltage can be obtained. Also, the arrangement pitch p of the conductors 11
It is desirable to adjust the pitch of the electrical connectors and connection terminals to be connected depending on the conductor diameter.

The coating 12a formed on the conductor 11 is softened to facilitate extrusion. Therefore, the coating 12a is soft and easily deformed by heating. In the present invention, after the coating 12a is formed by the forming roller 14, in order to impart a desired hardness to the coating 12a,
Irradiation crosslinking of γ rays is performed by the irradiation crosslinking device 15. The irradiation amount of this irradiation crosslinking is desirably 20 to 200 kGy,
If it is less than 20 kGy, it is not enough to suppress heat deformation, and if it exceeds 200 kGy, it becomes too hard. Coating 12
If a becomes too hard, the mountability such as terminal connection deteriorates.
Note that an electron beam other than γ-ray may be used for irradiation crosslinking.

FIGS. 3 and 4 show other shapes of the multi-core flat insulated wire and the shape of the processed end. FIG. 3 (A)
Multi-core flat insulated wire 10 with one side (bottom in the figure) flat
b. This multi-core flat insulated wire 10b
Can be fixed by applying an adhesive to the flat surface 20 and bonding and fixing the flat surface 20 to a wall surface or the like in the wiring device. Further, by providing the cuts 21 at the connection portions of the conductor coatings, it is possible to easily separate the conductors with the cuts 21.

FIG. 3 (B) shows an end-processed shape of the multi-core flat insulated wire 10b of FIG. 3 (A).
The connection conductor 22 is formed by removing b. Depending on the connection mode, the wire 21 can be separated into single-core insulated wires using the cuts 21 and the conductor spacing can be increased to facilitate electrical connection such as solder connection.

FIG. 4A shows a multi-core flat insulated wire 10c in which the coverings of the respective conductors are integrated by a connecting portion 23 which can be easily separated. Both ends of the connecting portion 23 are provided with cuts 24 that are easy to cut, and by cutting out the connecting portion 23, a single-core insulated wire can be obtained. It is the same as that of FIG. 3A in that it can be separated into single-core insulated wires, but is suitable when the arrangement pitch of the conductors is large.
It is suitable for the insulation displacement terminal connection shown in (1).

FIG. 4B shows a processed end shape of the multi-core flat insulated wire 10c of FIG. 4A. End connection 2
3 is partially removed in a U-shape as indicated by 25 to obtain a connection piece 26 in a state where the end is covered. This connection piece 26
As shown in FIG. 4 (C), the insulation coating 10c is automatically pierced by press-fitting in a direction indicated by an arrow into a well-known press contact terminal 27 frequently used for electrical connection to form an electrical connection. Is done.

FIG. 5 is a schematic view showing a manufacturing flow of the multi-core flat insulated wire of the present invention. First, in step S1, a coating tape is extruded from a molding resin according to the present invention for insulating coating. In step S2, a plurality of conductors arranged in a line at a predetermined interval are sandwiched by the extruded covering tape, and the conductor and the covering tape are integrally laminated with a pair of forming rollers, and are pressed and molded to a predetermined pressure. An insulating coating is formed in the shape. Thereafter, in step S3, irradiation crosslinking with γ-rays is performed to make the formed coating a predetermined hardness.
In step S4, the multi-core flat insulated wire is cut into a predetermined length as necessary, and both ends are processed into a shape adapted to electrical connection.

Next, the resin for molding an insulating coating of the present invention will be described with reference to specific examples. Ethylene vinyl acetate resin (abbreviation: EVA) is used as a base resin of the insulating covering material used in the present invention. The flowability (MI: g / 10 min) is changed by changing the content of vinyl acetate (abbreviation: VA) of the base resin and adjusting the molecular weight. The flowability (MI) measurement method conforms to JIS6370. Also, magnesium hydroxide is added as a flame retardant. Table 1
The γ-ray irradiation amount was changed to 50 kGy, 100 kGy, and 1 g by changing the content of vinyl acetate and the addition amount of magnesium hydroxide.
The characteristics at 50 kGy are shown.

[0020]

[Table 1]

From the results shown in Table 1, when the vinyl acetate content of the base resin is 19% (MI = 150), the flowability of the resin is large, lamination by a molding roller is impossible, and 33% (MI = 30). In (2), the forming roller was sticky, and the lamination could not be performed favorably. When the content of vinyl acetate was 25% or 28%, good results were obtained with good moldability and no stickiness to the forming roller. Therefore, the content of vinyl acetate with respect to the base resin is preferably set to 22 to 30% by weight.
The flowability of the resin is adjusted by the molecular weight. The lower the molecular weight, the greater the stickiness, and the higher the molecular weight, the less the stickiness, and there is no particular correlation with the VA content.

Various flame retardants other than halogen compounds are known as flame retardants for imparting flame retardancy, but use of magnesium hydroxide is suitable in consideration of miscibility with a base resin, environmental problems, and the like. . Increasing the amount of magnesium hydroxide reduces the elongation of the insulating coating. Since the elongation rate also decreases with an increase in the amount of γ-ray irradiation, 100% if the amount of irradiation is 150 kGy or less.
In order to secure the above elongation, the amount of magnesium hydroxide added is desirably 210 parts by weight or less. Irradiation dose 200kGy
Below, 200 parts by weight or less is preferable. When the amount of magnesium hydroxide is 120 parts by weight or less, flame retardancy cannot be obtained. The tensile strength has a desired value of 10.4 MPa or more, increases with an increase in the amount of magnesium hydroxide added, does not significantly change depending on the irradiation amount, and has a VA of 22.
There is no particular problem within the content range of ３０30% by weight.

[0023]

As is apparent from the above description, according to the present invention, a flame-retardant multi-core flat insulated wire can be formed without using a halogen compound without impairing device mounting properties such as connection of a pressure contact terminal. can do.

[Brief description of the drawings]

FIG. 1 is a view schematically showing the production of a flame-retardant multi-core flat insulated wire of the present invention.

FIG. 2 is a view showing a state of coating the flame-retardant multi-core flat insulated wire of the present invention.

FIG. 3 is a diagram showing another molded shape and a terminal processed shape of the flame-retardant multi-core flat insulated wire of the present invention.

FIG. 4 is a view showing other formed shapes and end processed shapes of the flame-retardant multi-core flat insulated wire of the present invention.

FIG. 5 is a diagram showing a manufacturing flow of the flame-retardant multi-core flat insulated wire of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Multi-core flat insulated wire, 11 ... Conductor, 12 ... Coating tape, 13 ... T die, 14 ... Forming roller, 15 ... Irradiation crosslinking device.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B29C 47/90 B29C 47/90 5G311 63/02 63/02 5G315 C08J 7/00 CES C08J 7/00 CESSZ 302 302 C08K 3/22 C08K 3/22 C08L 23/08 C08L 23/08 H01B 7/295 H01B 13/00 525G 13/00 525 525D B29K 23:00 // B29K 23:00 105: 16 105: 16 505: 00 505: 00 B29L 9:00 B29L 9:00 31:34 31:34 H01B 7/34 BF term (reference) 4F073 AA12 AA32 BA11 BB01 CA41 4F203 AA10 AB11 AB16 AD03 AD15 AG01 AG03 AH35 DA08 DB02 DB18 DC07 DJ01 DJ05 DJ08 DN06 DW23 DW25 4F207 AA10 AB11 AB16 AD03 AD15 AG01 AG03 AH35 KA01 KA17 KB18 KB20 KJ05 KK81 KK88 KL63 KW23 KW26 KW33 4F211 AA10 AB16 AD03 AD15 AG03 AH35 SA0 7 SD01 SG01 SP04 SW50 4J002 BB061 DE076 FD136 GQ01 5G311 CA01 CB01 CC01 CD03 CF04 5G315 CA03 CB02 CC08 CD04 CD14

Claims (5)

[Claims] 1. A flame-retardant multi-core flat insulated wire not containing a halogen compound, wherein the insulating coating is a molding resin obtained by adding magnesium hydroxide to an ethylene vinyl acetate resin containing 22 to 30% by weight of vinyl acetate. A flame-retardant multi-core flat insulated wire, characterized in that the wire is formed by cross-linking by gamma irradiation. 2. The flame-retardant multi-core flat insulated wire according to claim 1, wherein the magnesium hydroxide is added in an amount of 150 to 200 parts by weight based on 100 parts by weight of the ethylene vinyl acetate resin. 3. The flame-retardant multi-core flat insulated wire according to claim 1, wherein the irradiation amount of the γ-ray irradiation is 20 kGy or more and 200 kGy or less. 4. A method for producing a flame-retardant multi-core flat insulated electric wire which does not contain a halogen compound, comprising: a molding resin in which magnesium hydroxide is added to an ethylene vinyl acetate resin containing 22 to 30% by weight of vinyl acetate. A coating tape is formed by extrusion molding, and then a plurality of conductors arranged in a line at predetermined intervals are sandwiched between the both sides by the coating tape, laminated by a forming roller and pressed and formed to form an insulating coating, Thereafter, the insulating coating is cross-linked by γ-irradiation to produce a flame-retardant multi-core flat insulated wire. 5. The flame-retardant multi-core flat wire according to claim 4, wherein the flame-retardant flat insulated wire is cut into a predetermined length, and both ends are processed so as to be connectable to a press-contact terminal. Manufacturing method of insulated wire.