JP7014414B2 - Plating fiber and electric wire - Google Patents

Description

The present invention relates to a plated fiber having a plated film on the fiber and an electric wire using the plated fiber.

Conventionally, it has been known that a plated fiber having a metal plating film formed on the fiber is used for an electromagnetic shield cloth, an antistatic cloth, a conductive cloth, a light-shielding cloth and the like.

Further, in recent years, it has been studied to reduce the weight and cost of electric wires by replacing copper wires as electric wires with plated fibers having a copper plating film formed on the fibers (Patent Documents 1 and 1). 2).

However, since the copper plating film is easily oxidized and easily worn, the plated fibers are liable to deteriorate with time such as discoloration and increase in resistance value.

Therefore, a tin-plated film formed in contact with the copper-plated film has also been studied (Patent Document 3). Since tin has a higher ionization tendency than copper, it is more easily oxidized than copper, but unlike copper, the oxide film is less likely to discolor and remains white. In addition, since tin acts as a sacrificial anode of copper, it has the function of delaying the oxidation of copper and the increase in resistance value. Therefore, it can be expected to prevent the deterioration of the plated fiber over time. Further, the tin-plated film has an advantage that it has good solderability.

However, according to the study of the present inventor, when a tin-plated film was formed in contact with the copper-plated film and subjected to a salt spray test, the color changed to red-black in the observation after one cycle, and the resistance value was also high. It was found that the increase was unmeasurable and did not meet the above expectations. It is considered that this is because the copper in the copper plating film diffuses into the tin plating film.

Japanese Patent Application Laid-Open No. 2003-171869 Japanese Unexamined Patent Publication No. 2009-2428839 Japanese Unexamined Patent Publication No. 2012-87434

Therefore, an object of the present invention is to prevent deterioration over time such as discoloration and increase in resistance value of a plated fiber having a copper plating film on a non-metal fiber and an electric wire using the plated fiber.

In the present application, "on top of ..." means in contact with ... or through another membrane.
In the present application, the "nickel-based plating film" means a nickel plating film, a nickel alloy plating film, or a nickel composite plating film.

(1) The plating fiber of the reference invention is characterized by including a non-metal fiber, a copper plating film formed on the non-metal fiber, and a nickel-based plating film formed on the copper plating film. ..

[Action]
The nickel-based plating film suppresses the diffusion of copper in the copper plating film. Further, the nickel-based plating film protects the copper plating film from oxidation and wear, and the nickel-based plating film itself is less likely to be oxidized and worn than the copper plating film. As a result, it is possible to prevent deterioration over time such as discoloration of the plated fiber, increase in resistance value, and wear.

(2) The plating fiber of the present invention is a non-metal fiber, a copper plating film formed on the non-metal fiber, a nickel-based plating film formed on the copper plating film, and a nickel-based plating film. A plating fiber containing a tin-plated film formed on the surface of the plating fiber.
The tin-plated film is the outermost layer as a plating layer for plating fibers.
The nickel-based plating film is for suppressing the copper of the copper plating film from diffusing into the tin plating film, and has a film thickness of 0.1 μm or more.
The plated fiber is characterized in that there is no discoloration in the observation after 3 cycles of the salt spray test according to JIS Z2371, and there is no increase in resistance value as compared with that before the salt spray test .

[Action]
The nickel-based plating film suppresses the diffusion of copper in the copper plating film into the tin plating film. Further, since the tin-plated film can suppress the diffusion of copper into tin by sandwiching it between the copper-plated film and the tin-plated film, the plated fiber is less likely to cause deterioration over time such as discoloration and increase in resistance value.

(3) The electric wire of the present invention is characterized in that it is constructed by using the plated fiber of (2) above .

According to the present invention, it is possible to prevent deterioration over time such as discoloration and increase in resistance value of a plated fiber having a copper plating film on a non-metal fiber and an electric wire using the plated fiber.

1A and 1B show a quarter portion of a cross section of one filament of the plated fiber plated in the examples, FIG. 1A is a cross-sectional view of Examples 1 to 4, and FIG. 1B is a cross-sectional view of Example 5. c) is a cross-sectional view of Comparative Example 1. FIG. 2 is a perspective view of a non-metal fiber (which can be used as an electric wire after the plating treatment) to be plated in the embodiment.

<1> Non-metal fiber The non-metal fiber is not particularly limited, but the following (a), (b) and (c) can be exemplified.
(A) Organic fiber / synthetic fiber: polyester fiber (polyethylene terephthalate (PET) fiber, polybutylene terephthalate (PBT) fiber, etc.), polyolefin fiber (polyethylene (PE) fiber, polypropylene (PP) fiber, etc.), vinylon fiber, Rayon fiber, nylon fiber, polycarbonate fiber, polyacetal fiber, acrylic fiber, polyamide fiber, aramid fiber, etc.
-Natural fibers: cotton, linen, silk, bamboo, etc.
(B) Inorganic fiber Glass fiber, mineral fiber, ceramic fiber, silica fiber, etc.
(C) As the fibers of the plated fibers used as electric wires, para-aramid fibers having high tensile strength, PBO (poly (p-phenylenebenzobisoxazole)) fibers, polyarylate fibers, ultra-high molecular weight polyethylene fibers and the like are preferable. Further, fibers having a tensile strength of 15 cN / dtex or more are preferable, but fibers having a low tensile strength of, for example, 6 to 8 cN / dtex can be dealt with by using thick fibers having a fineness of 100 dtex or more.
The non-metal fiber may be a monofilament or a multifilament (a bundle of a plurality of filaments). The diameter of one filament is not particularly limited, and can be exemplified by 10 to 200 μm. In the case of multifilament, the diameter of one filament is preferably 10 to 25 μm.

<2> Pretreatment For non-metal fibers, it is preferable to perform a pretreatment for the purpose of improving plating adhesion and the like before the plating treatment. The pretreatment is not particularly limited, but the following (a) and (b) can be exemplified.
(A) Wet pretreatment Alkaline etching → neutralization → surface adjustment → catalyst application → activation can be performed in this order.
The surface adjustment can be performed, for example, by immersing in a cationic surfactant solution.
The catalyst application can be carried out, for example, by immersing in a tin-palladium colloid.
Activation is, for example, the step of immersing in an acid or alkaline solution to dissolve the colloidal stannous chloride.
(B) Dry pretreatment Supercritical nucleation → heat treatment (reduction) can be performed in this order.
Supercritical nucleation can be performed by placing a palladium complex that is in a supercritical state at high temperature and high pressure in a chamber and adhering palladium to the fiber in the supercritical state.

<3> Conductivity-imparting film For the next electroplating, it is preferable to form a metal continuity-imparting film in contact with the surface of the non-metal fiber after the pretreatment.
The film thickness of the conductivity-imparting film is not particularly limited, but is preferably 0.1 to 1 μm.
The continuity-imparting film can be formed by, for example, electroless plating of copper or the like.

<4> Copper plating film The thickness of the copper plating film is not particularly limited, but is preferably thicker than other plating films because it is the main conductive film of the plating fiber, for example, 0.5 to 4 μm is preferable. It is more preferably ~ 3.5 μm.
Further, when a wire is formed by using a plurality of plated fibers of the present invention, it is preferable that the resistance value of the wire is 0.2 to 20 Ω / m.
The copper plating film can be formed by electroplating or the like.

<5> Nickel-based plating film The nickel-based plating film is a nickel plating film, a nickel alloy plating film, or a nickel composite plating film as described above. The nickel alloy of the nickel alloy plating film is not particularly limited, and examples thereof include a nickel-phosphorus alloy, a nickel-boron alloy, a nickel-chromium alloy, a nickel-cobalt alloy, and a nickel-zinc alloy.
The film thickness of the nickel-based plating film is not particularly limited, but is preferably 0.1 to 1 μm. If it is 0.1 μm or more, the diffusion of copper can be suppressed, and if it is 1 μm or more, the suppleness peculiar to the plated fiber is lost and the production cost is high.
The nickel-based plating film can be formed by electroless plating, electroplating, or the like.

<6> Tin-plated film The thickness of the tin-plated film is not particularly limited, but is preferably 0.1 to 1 μm.
The tin plating film can be formed by electroless plating, electroplating, or the like.

<7> Discoloration inhibitor The plated fiber is preferably formed by applying a discoloration inhibitor in contact with the tin plating film of the outermost layer. The discoloration inhibitor is not particularly limited, and examples thereof include thioether-based, thiol-based, Ni-based organic compound-based, benzotriazole-based, imidazole-based, oxazole-based, tetrazyneden-based, pyrimidine-based, thiadiazole-based, and the like.

<8> Use of plated fiber The use of the plated fiber of the present invention is not particularly limited, but an electric wire is suitable, and the cloth (woven cloth, knitted fabric, non-woven fabric, etc.) is further processed into an electromagnetic shield cloth, an antistatic cloth, and the like. It can also be used for conductive cloth and light-shielding cloth.

Next, examples of the present invention will be described with reference to the drawings. The structure, material, shape and dimensions of each part of the embodiment are examples and can be appropriately changed without departing from the spirit of the invention.

The plated fibers of Examples 1 to 5 and Comparative Example 1 shown in Table 1 below (marked with ◯ are elements included in each example) were prepared (however, Example 5 is a reference example) . Examples 1 to 5 are different from each other in the types of nickel-based plating films, and Example 5 is different from other examples in that there is no tin plating film. The comparative example differs from the example in that there is no nickel-based plating film.

Here, the specifications and forming method of each element will be described in detail.
<1> Non-metal fibers In all cases, the non-metal fibers include para-aramid fibers having a fineness of, for example, 440 dtex-267f (267 filaments are gathered to form one bundle (440 dtex)). It was used. FIG. 1 shows one filament (diameter: 12 μm) in one bundle and a quarter portion of a cross section of a plating film or the like formed on the filament.

<2> Pretreatment In all cases, para-aramid fibers were pretreated by a wet pretreatment method. The wet pretreatment method was carried out using the above-mentioned materials in the order of alkali etching → acid neutralization → surface preparation → catalyst application → activation described above. As shown in FIGS. 1 and 1, a catalyst (palladium nucleus) having a film thickness of about 50 nm was in contact with and adhered to the non-metal fiber.

<3> Conductivity-imparting film In all cases, in order to impart conductivity (necessary for electroplating of the next copper plating film) to para-aramid fibers, the film is in contact with the catalyst and has a film thickness of 0.3 μm. The imparting film was formed by electroless copper plating. The plating solution used is an aqueous solution having the following composition. EDTA-4Na is ethylenediaminetetraacetic acid / tetrasodium.
Copper sulphate 15g / L
Formalin 3g / L
EDTA-4Na 35g / L
Sodium hydroxide 5g / L
Stabilizer Small amount Lubricant Small amount

<4> Copper plating film In all cases, as the main conductive film of the plating fiber, a copper plating film having a film thickness of 3.0 μm was formed by electroplating on the continuity-imparting film. The plating solution used is an aqueous solution having the following composition.
Copper sulfate 200g / L
Sulfuric acid 50g / L

<5> Nickel-based plating film (a) Nickel plating film (electricity)
In Example 1, a nickel plating film having a film thickness of 0.5 μm was formed by electroplating in contact with the copper plating film. The plating solution used is an aqueous solution having the following composition.
Nickel sulfate 240g / L
Nickel chloride 45g / L
Boric acid 30g / L

(B) Nickel-phosphorus alloy plating film (electroless)
In Example 2, a nickel-phosphorus plating film having a film thickness of 0.3 μm was formed by electroless plating in contact with the copper plating film. The plating solution used was the trade name "Top Nicolon P-13" of Okuno Pharmaceutical Industry Co., Ltd.

(C) Nickel-phosphorus alloy plating film (electricity)
In Examples 3 and 5, a nickel-phosphorus plating film having a film thickness of 0.4 μm was formed by electroplating on the copper plating film. The plating solution used is an aqueous solution having the following composition.
Nickel sulfate 250g / L
Sodium hypophosphite 40 g / L
Citric acid 15g / L

(D) Nickel-boron alloy plating film (electroless)
In Example 4, a nickel-boron plating film having a film thickness of 0.3 μm was formed by electroless plating in contact with the copper plating film. The plating solution used was the trade name "Top Chemi Alloy 66" of Okuno Pharmaceutical Industry Co., Ltd.

<6> Tin-plated film In Examples 1 to 4, the tin-plated film having a thickness of 0.5 μm was electroplated in contact with the nickel-based plating film and in Comparative Example 1 on the copper-plated film. Formed by. The plating solution used is an aqueous solution having the following composition.
Stannous sulfate 30 g / L
Sulfuric acid 105mlg / L
Appropriate amount of brightener

<7> Anti-tarnish agent In Examples 1 to 4 and Comparative Example 1, the anti-tarnish agent was applied and formed in contact with the tin-plated film and in Example 5 on the nickel-based plating film. The discoloration inhibitor used was "Top Rust Inhibitor Y" manufactured by Okuno Pharmaceutical Industry Co., Ltd.

The plated fibers of Examples 1 to 5 and Comparative Example 1 prepared as described above were subjected to a salt spray test in accordance with JIS Z2371. Each plated fiber was placed in a test tank whose temperature was maintained at 35 ° C., salt water having a concentration of 5% was sprayed, the surface was observed after each test cycle, and the resistance value was measured.

As a result, the plated fiber of Comparative Example 1 was discolored red and black in the observation after one cycle of the test, and the resistance value increased beyond measurement.
On the other hand, the plated fibers of Examples 1 to 5 showed almost no discoloration in the observation after 3 cycles of the test, and the resistance value did not increase from 1 to 1.5 Ω / m before the salt spray test. It is considered that this is because the diffusion of copper was suppressed by forming the nickel-based plating film on the copper plating film.

Since the plated fibers of Examples 1 to 5 have a resistance value in the range of 0.2 to 20 Ω / m in one bundle shown in FIG. 2, they can be particularly preferably used as an electric wire.

The present invention is not limited to the above embodiment, and can be appropriately modified and embodied without departing from the spirit of the invention.

Claims (6)

It includes a non-metal fiber, a copper plating film formed on the non-metal fiber, a nickel-based plating film formed on the copper plating film, and a tin plating film formed on the nickel-based plating film. It is a plated fiber
The tin-plated film is the outermost layer as a plating layer for plating fibers.
The nickel-based plating film is for suppressing the copper of the copper plating film from diffusing into the tin plating film, and has a film thickness of 0.1 μm or more.
The plated fiber is a plated fiber according to JIS Z2371, which is characterized by no discoloration in observation after 3 cycles of the salt spray test and no increase in resistance value as compared with that before the salt spray test . The plated fiber according to claim 1, wherein the thickness of the copper plating film is 0.5 to 4 μm. The plating fiber according to claim 1 or 2, wherein the nickel-based plating film has a film thickness of 0.1 to 1 μm. The plated fiber according to claim 1, 2 or 3, wherein the tin-plated film has a film thickness of 0.1 to 1 μm. An electric wire made by using the plated fiber according to any one of claims 1 to 4. The electric wire according to claim 5, wherein the resistance value of the electric wire is 0.2 to 20 Ω / m.

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