Barbed wire and its manufacturing method

Abstract

The present invention aims to provide a barbed wire that does not use expensive materials, has excellent corrosion resistance, is hard to notice at night, and maintains its intrusion prevention effect for a long period of time. Another object of the present invention is to provide a method for producing a rust remover that can easily produce such barbed wire. [Solution] The barbed wire of the present invention is used in intrusion prevention fences and is characterized in that it comprises a base material having an iron or steel wire and a number of barbs attached to the wire, a zinc-containing plating layer formed on the surface of the base material, and a powder paint layer formed on the plating layer, with the powder paint layer having a thickness of 100 μm or more.

Description

[Technical field]

[0001] The present invention relates to barbed wire and a method for manufacturing barbed wire, and more particularly to barbed wire used in intrusion prevention fences that prevent intruders from entering facilities, and a method for manufacturing the same. [Background technology]

[0002] Conventionally, in facilities where it is necessary to restrict access to unauthorized persons (for example, military facilities, nuclear power plants, oil refineries, etc.), intrusion prevention fences made of barbed wire are used to prevent intrusion by unauthorized persons. Such intrusion prevention fences are obtained by stretching barbed wire wound in a spiral shape. Then, the intrusion prevention fence is laid in the facility.

[0003] The installed intrusion prevention fence needs to maintain its intrusion prevention effect for a long period of time. Therefore, it is desirable to use barbed wire that is resistant to rust and has excellent durability for a long period of time. A typical barbed wire is composed of an iron core material and a barb material, and the surface of the core material and the barb material is zinc-plated to prevent corrosion. Such barbed wire has the advantage of being inexpensive and easy to process into a desired shape, but has the problem that the zinc plating peels off over time and the corrosion resistance is insufficient. Normally, the product life of iron barbed wire is about 2 to 3 years. In addition, when the barbed wire is exposed to seawater or sea air, the life of the barbed wire is further shortened due to salt damage. Furthermore, since the barbed wire that is zinc-plated is easily light-reflective, it is easily noticed by intruders at night, and the intrusion prevention effect is insufficient.

[0004] Barbed wires using titanium or stainless steel as a core material, which has a higher corrosion prevention effect, are also used. However, titanium barbed wires are very expensive, so when an intrusion prevention fence is laid over a wider area, the cost of laying the intrusion prevention fence becomes too high. In addition, titanium barbed wires are less rigid and more easily deformed than iron barbed wires, so they do not provide sufficient intrusion prevention effect. In addition, stainless steel barbed wires are more likely to reflect light than iron barbed wires. Furthermore, it is difficult to apply coating agents such as matting agents to stainless steel barbed wires, so it is difficult to suppress light reflection. Therefore, stainless steel barbed wires are easily noticed by intruders at night, and the intrusion prevention effect is insufficient.

[0005] Also, from the viewpoint of improving corrosion resistance, barbed wires using resin materials instead of metal materials as the constituent materials of the core material and barb material are known (for example, Patent Document 1). However, barbed wires made of resin materials are inferior to barbed wires made of metal materials in properties such as impact resistance, abrasion resistance, weather resistance, and heat resistance, and there is a problem that they do not provide sufficient intrusion prevention effect. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Publication number 7-9629 Summary of the Invention [Problem to be solved by the invention]

[0007] The object of the present invention is to provide a barbed wire that does not use expensive materials, has excellent corrosion resistance, is hard to notice at night, and maintains its intrusion prevention effect for a long period of time. Another object of the present invention is to provide a method for manufacturing such barbed wire that can easily manufacture such barbed wire. [Means for solving the problem]

[0008] These objects can be achieved by the present invention as set forth below in (1) to (13). (1) Barbed wire used in intrusion prevention fences, A base material having an iron or steel wire and a plurality of barbs attached to the wire; a zinc-containing plating layer formed on the surface of the base material; A powder coating layer formed on the plating layer, A barbed wire characterized in that the powder coating layer has a thickness of 100 μm or more.

[0009] (2) The barbed wire according to (1) above, wherein the thickness of the plating layer is 20 μm or more and 80 μm or less.

[0010] (3) The barbed wire according to (1) or (2) above, in which, when the thickness of the powder coating layer is T1 [μm] and the thickness of the plating layer is T2 [μm], the relationship of 1.25≦T1 / T2≦8 is satisfied.

[0011] (4) The barbed wire according to (1) or (2) above, wherein the powder coating layer contains inorganic particles and a thermosetting resin.

[0012] (5) The barbed wire according to (4) above, wherein the inorganic particles contain silica, barium sulfate and calcium carbonate.

[0013] (6) The barbed wire according to (4) above, wherein the thermosetting resin contains a thermosetting polyester resin.

[0014] (7) A method for manufacturing barbed wire for use in intrusion prevention fences, comprising the steps of: preparing a base material by attaching a plurality of barbs to an iron or steel wire; forming a zinc-containing plating layer on a surface of the base material; and forming a powder coating layer on the plating layer to obtain the barbed wire. A method for manufacturing barbed wire, characterized in that the powder paint layer has a thickness of 100 μm or more.

[0015] (8) The step of forming the powder coating layer comprises: preparing a powder coating; spraying the powder paint onto the plating layer to adhere the powder paint onto the plating layer; The method for manufacturing barbed wire described in (7) above, further comprising a step of heating the powder paint to form the powder paint layer.

[0016] (9) The step of applying the powder paint includes a step of spraying the powder paint onto the plating layer using an electrostatic powder sprayer having a discharge port and a corona electrode at the discharge port; The method for manufacturing barbed wire described in (8) above includes a step of applying a voltage to the corona electrode of the electrostatic powder sprayer to generate an electric field between the electrostatic powder sprayer and the plating layer, thereby charging the powder paint.

[0017] (10) The method for manufacturing barbed wire according to (9) above, wherein the step of forming the powder coating layer is carried out at 200 to 285°C.

[0018] (11) A method for manufacturing barbed wire as described in (7) above, wherein the step of preparing the base material includes the steps of preparing a long plate material on which the barbs are formed, and wrapping and fixing the wire in the plate material.

[0019] (12) The base material is formed into a cylindrical shape by winding the wire in a spiral shape, The method for manufacturing barbed wire according to any one of (7) to (11) above, wherein the step of forming the plating layer and the step of forming the powder coating layer are performed on the cylindrical base material.

[0020] (13) The barbed wire is formed into a cylindrical shape, The length of the cylindrical base material is the same as the length of the cylindrical barbed wire; The method for manufacturing barbed wire described in (12) above, wherein the diameter of the cylindrical base material is the same as the diameter of the cylindrical barbed wire. Effect of the Invention

[0021] According to the present invention, a barbed wire having a surface formed with a powder coating layer having a thickness of 100 μm or more in addition to a zinc-containing plating layer can be obtained, which makes it difficult for the barbed wire to rust and has reduced light reflection. This barbed wire has excellent corrosion resistance, is hard to notice at night, and maintains its intrusion prevention effect for a long period of time. [Brief description of the drawings]

[0022] [Figure 1] FIG. 1(a) is a photograph showing a preferred embodiment of the helically wound barbed wire of the present invention, and FIG. 1(b) is a partially enlarged photograph of FIG. 1(a). [Diagram 2] Figure 2 is a diagram for explaining the process of preparing a base material, where Figure 2(a) is a diagram showing a barbed plate material on which barbs have been formed, Figure 2(b) is a diagram showing a state in which a wire has been placed in the center of the barbed plate material, and Figure 2(c) is a diagram showing the state in which the barbed plate material has been processed from the state in Figure 2(b) so that the wire is wrapped in it. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the barbed wire and the method for manufacturing the barbed wire of the present invention will be described in detail with reference to the accompanying drawings. 1. Barbed wire First, the barbed wire of the present invention will be described. Fig. 1(a) is a photograph showing a preferred embodiment of the barbed wire of the present invention wound in a spiral shape, and Fig. 1(b) is a partially enlarged photograph of Fig. 1(a).

[0024] The barbed wire 1 of this embodiment has a base material, a plating layer formed on the surface of the base material, and a powder coating layer formed on the plating layer. Such barbed wire 1 is used as an intrusion prevention fence installed around a facility where it is necessary to restrict access to unauthorized persons in order to prevent unauthorized persons from invading. The barbed wire 1 is wound in a spiral shape and formed into a cylindrical shape. As shown in FIG. 1(a), such barbed wire 1 is transported to the site where it is to be laid in a wound state. After arriving at the site, the barbed wire 1 is stretched in a direction perpendicular to the winding direction of the barbed wire 1 to form a spiral shape, so that it can be used as an intrusion prevention fence. In addition, multiple barbed wires 1 can be prepared, and ends of the barbed wires 1 that have been stretched to form a spiral shape can be joined together, or these barbed wires 1 can be stacked in the height direction to be used as an intrusion prevention fence. Each component that constitutes the barbed wire 1 will be described below.

[0025] (base material) The base material of the barbed wire 1 has a wire 2 and a plurality of barbs 3 attached to the wire 2. The shape of the base material is the same as the shape of the barbed wire 1 shown in Figures 1(a) and (b).

[0026] The wire 2 is made of iron or steel. The wire 2 preferably has a wire diameter that allows the barbed wire 1 to have sufficient strength while being difficult for intruders to notice at night. Specifically, the wire diameter of the wire 2 is preferably about 1.0 to 4.0 mm, more preferably about 1.5 to 3.5 mm, and even more preferably about 2.0 to 3.0 mm. If the wire diameter of the wire 2 is within the above range, it is possible to obtain an intrusion prevention fence that has sufficient strength while being difficult for intruders to notice at night and that exhibits a high intrusion prevention effect. Furthermore, the cross-sectional shape of the wire 2 is not particularly limited, but may be any shape, such as a circle, an ellipse, a rectangle, a square, a triangle, or any other polygon.

[0027] Furthermore, the length of the wire 2 is not particularly limited, but from the viewpoint of being easily transportable and being able to install an intrusion prevention fence of sufficient length even with a small number of sets of barbed wire 1, it is preferable that the length be approximately 150 to 300 m, and more preferably approximately 200 to 270 m.

[0028] The barbed object 3 is a razor blade (a razor blade) made of iron or steel, a barbed wire having a sharp tip, or the like. In particular, by using a laser blade as the barbed object 3, it is possible to significantly deter intruders from entering the facility psychologically, thereby enhancing the intrusion prevention effect. In this embodiment, a case where a laser blade, which has a high intrusion prevention effect, is used as the barbed object 3 will be described.

[0029] As shown in FIG. 1(b), the barbed bodies (razor blades) 3 are provided symmetrically with respect to the wire 2 in the radial direction of the wire 2. The barbed bodies 3 are provided at predetermined intervals along the longitudinal direction of the wire 2. The blade thickness of the barbed bodies 3 is preferably about 0.3 to 0.8 mm, more preferably about 0.4 to 0.7 mm, and even more preferably about 0.45 to 0.6 mm. If the blade thickness of the barbed bodies 3 is within the above range, the barbed bodies 3 will have sufficient durability and the barbed wire 1 will have a high intrusion prevention effect.

[0030] Furthermore, the blades of the barbed bodies 3 are preferably about 5 to 15 mm in the longitudinal direction of the wire 2, more preferably about 7 to 12 mm, and even more preferably about 9 to 11 mm. If the longitudinal length of the barbed bodies 3 is within the above range, the intrusion prevention effect of the barbed wire 1 can be further improved. Furthermore, the predetermined interval (pitch) of the barbed bodies 3 is preferably about 17 to 35 mm, more preferably about 20 to 30 mm, and even more preferably about 23 to 27 mm. If the pitch of the barbed bodies 3 is within the above range, the intrusion prevention effect of the barbed wire 1 can be further improved.

[0031] (Plating layer) In this embodiment, a zinc-containing plating layer is formed on the surface of the base material 10 having the plurality of barbed members 3 attached to the wire 2 described above. The metal material constituting the plating layer may be zinc or a zinc alloy of zinc with various metals such as nickel, aluminum, iron, etc. In particular, it is preferable that the plating layer is composed of zinc alone, since zinc has a high affinity with the iron and steel constituting the base material 10 and can form a plating layer that is firmly adhered to the surface of the base material 10.

[0032] The thickness of the plating layer formed on the surface of the base material 10 is preferably about 20 μm or more and 80 μm or less. If the thickness of the plating layer is within the above range, the plating layer can be firmly adhered to the surface of the base material 10 and the durability of the plating layer can be increased. If the durability of the plating layer is increased and peeling from the base material 10 is suppressed, the base material 10 can maintain a state covered with the plating layer and the powder paint layer for a long period of time. As a result, a barbed wire 1 having excellent corrosion resistance and a long product life can be obtained. In addition, if the thickness of the plating layer is within the above range, the luster derived from the base material 10 can be suppressed, making the barbed wire 1 less noticeable at night. In addition, from the viewpoint of enhancing the above effects, the thickness of the plating layer is more preferably about 22 μm or more and 70 μm or less, and even more preferably about 23 μm or more and 60 μm or less.

[0033] (powder coating layer) A powder coating layer formed by powder coating is formed on the plating layer. Powder coating is used as a method for forming such a powder coating layer. Since the powder coating uses a solvent-free powder coating, there is no environmental problem or risk of disaster caused by the solvent as in the case of a coating method using a solvent-containing paint. In addition, there is an advantage that the paint loss can be greatly reduced because the paint sprayed in excess during the process can be collected and reused. Specific powder coating processes will be described later.

[0034] The powder coating layer formed by the powder coating process is formed thicker than the plating layer formed by the plating process. Specifically, in this embodiment, the powder coating layer has a thickness of 100 μm or more. Generally, the thickness of the plating layer formed by plating is at most several tens of microns, and it is not possible to obtain a thickness of 100 μm or more. On the other hand, in the present invention, by forming a powder coating layer on the plating layer using a powder coating, the base material 10 can be covered with a thick coating, the corrosion resistance of the barbed wire 1 can be improved, and the product life can be dramatically extended. In addition, by making the coating of the base material 10 thicker, the gloss derived from the base material 10 can be suppressed. That is, since a zinc-containing plating layer and a powder coating layer having a thickness of 100 μm or more are formed on the surface of the barbed wire 1, the barbed wire 1 has excellent corrosion resistance, is difficult to notice at night, and maintains an intrusion prevention effect for a long period of time.

[0035] In this embodiment, the powder paint forming the powder paint layer contains inorganic particles, a thermosetting resin, and a curing agent for curing the thermosetting resin. Inorganic particles include silica (SiO 2 ), barium sulfate (BaSO 4 ), calcium carbonate (CaCO 3 ), titanium dioxide (TiO 2 ), aluminum oxide (Al 2 O 3 ), copper oxide (CuO), zinc oxide (ZnO), tin oxide (SnO 2 ), cerium oxide (CeO 2 ), iron oxide (Fe 2 O 3 ), magnesium oxide (MgO), barium oxide (BaO), calcium oxide (CaO), potassium oxide (K 2 O), sodium oxide (Na 2 O), zirconium oxide (ZrO 2 ), Magnesium carbonate (MgCO 3 ), magnesium sulfate (MgSO 4Among these, it is preferable that the inorganic particles contain silica particles, barium sulfate particles, and calcium carbonate particles.

[0036] Silica particles are SiO 2 The particles may be crystalline or amorphous as long as they are mainly composed of silica. The silica particles may be particles obtained by crushing quartz, or particles manufactured using silicon compounds such as water glass and alkoxysilane as raw materials. In particular, silica particles obtained by crushing quartz have a wider particle size distribution than silica particles obtained by a synthetic method, and therefore exhibit a matte effect that suppresses the gloss of the base material 10. Therefore, by using silica particles obtained by crushing quartz, the barbed wire 1 can be made less noticeable. In addition, the fluidity of the powder paint is improved by including silica particles in the powder paint. As a result, even when the powder paint layer is formed relatively thick, the thickness of the powder paint layer can be made more uniform, and the corrosion resistance of the barbed wire 1 can be further improved.

[0037] The average particle size of the silica particles is preferably about 5 nm to 120 nm, more preferably about 10 nm to 100 nm, and the content of the silica particles is preferably about 0.1 mass % to 5.0 mass %, more preferably about 0.1 mass % to 3.0 mass %, based on the total mass of the powder coating, from the viewpoint of improving the flowability of the powder coating. Furthermore, the silica particles may be subjected to a hydrophobic treatment using a silane coupling agent or the like in order to improve the affinity with the thermosetting resin.

[0038] The barium sulfate particles may be particles mainly composed of elutriated barium sulfate (baryte powder), which is a crushed product of barite mineral, a natural mineral called barite, or particles mainly composed of precipitated barium sulfate produced by chemical reaction. Such barium sulfate particles have an effective matting function. By including barium sulfate particles in the powder paint, the gloss of the base material 10 and the gloss of the powder coating layer itself can be suppressed, making the barbed wire 1 less noticeable.

[0039] The average particle size of the barium sulfate particles is preferably about 10 nm to 100 nm, more preferably about 15 nm to 90 nm. The content of the barium sulfate particles is preferably about 5 mass % to 25 mass %, more preferably about 10 mass % to 20 mass % based on the total mass of the powder paint, from the viewpoint of making the barbed wire 1 less noticeable.

[0040] The calcium carbonate particles may be particles made of light calcium carbonate (precipitated calcium carbonate) chemically produced using limestone as a raw material, or may be particles made of heavy calcium carbonate produced by crushing and classifying limestone. Such calcium carbonate particles have an effective matting function. By including calcium carbonate particles in the powder coating, the gloss derived from the base material 10 and the gloss of the powder coating layer itself can be suppressed, making the barbed wire 1 less noticeable. In addition, calcium carbonate (heavy calcium carbonate) particles obtained by crushing limestone have a wider particle size distribution than light calcium carbonate particles produced chemically, so that the gloss of the base material 10 can be more suppressed. Therefore, it is preferable to use heavy calcium carbonate particles from the viewpoint of making the barbed wire 1 less noticeable.

[0041] The average particle size of the calcium carbonate particles is preferably about 10 nm to 100 nm, and more preferably about 15 nm to 90 nm. From the viewpoint of making the barbed wire 1 less noticeable, the content of the calcium carbonate particles is preferably about 5 mass % to 25 mass %, and more preferably about 10 mass % to 20 mass %, based on the total mass of the powder paint.

[0042] The powder paint contains a thermosetting resin. When the powder paint contains a thermosetting resin, the powder paint is applied onto the plating layer of the base material 10 by, for example, an electrostatic powder coating method, and is heated, whereby the thermosetting resin is cured to form a powder paint film. As the thermosetting resin, various resins such as thermosetting polyester resin, thermosetting (meth)acrylic resin, thermosetting fluorine-based resin (e.g., fluoroethylene-vinyl ether (FEVE) copolymer resin, etc.), epoxy resin, epoxy-polyester resin, etc. can be used. Among these thermosetting resins, it is preferable to use thermosetting polyester resin from the viewpoint of particularly excellent corrosion resistance, weather resistance, and water resistance.

[0043] The content of the thermosetting resin is preferably about 25% by mass to about 90% by mass, more preferably about 30% by mass to about 85% by mass, and even more preferably about 35% by mass to about 80% by mass, based on the total mass of the powder coating. If the content of the thermosetting resin is within the above range, the powder coating layer can be firmly adhered to the plating layer, and the durability (corrosion resistance, weather resistance, etc.) of the powder coating layer can be further improved.

[0044] The powder coating also contains a curing agent that corresponds to the type of thermosetting reactive group of the thermosetting resin. The curing agent is not particularly limited, but in the case where a thermosetting polyester resin is used as the thermosetting resin, for example, triglycidyl isocyanurate, β-hydroxyalkylamide, various epoxy resins (e.g., polyglycidyl ether of bisphenol A, etc.), epoxy group-containing acrylic resins (e.g., glycidyl group-containing acrylic resins, etc.), polyglycidyl ethers of various polyhydric alcohols (e.g., 1,6-hexanediol, trimethylolpropane, trimethylolethane, etc.), polyglycidyl esters of various polyvalent carboxylic acids (e.g., phthalic acid, terephthalic acid, isophthalic acid, hexahydrophthalic acid, methylhexahydrophthalic acid, trimellitic acid, pyromellitic acid, etc.), various alicyclic epoxy group-containing compounds (e.g., bis(3,4-epoxycyclohexyl)methyl adipate, etc.), etc. can be used. The content of the curing agent is preferably about 0.5% by mass or more and 15% by mass or less, and more preferably about 1% by mass or more and 10% by mass or less, based on the total mass of the powder coating.

[0045] The powder coating may also contain a thermoplastic resin. Examples of such thermoplastic resins include various thermoplastic resins such as polyethylene resin, vinyl resin such as polyvinyl chloride resin, polyamide resin, and fluororesin. Among these thermoplastic resins, it is preferable to use polyethylene resin. By including polyethylene resin in the powder paint, the powder paint layer is given appropriate flexibility, and it is possible to prevent cracks and the like from occurring in the powder paint layer. In addition, since polyethylene has almost no water absorption, it does not deteriorate the weather resistance and water resistance of the powder paint layer. Therefore, by using a powder paint containing polyethylene resin, a barbed wire 1 with better durability can be obtained.

[0046] The content of the thermoplastic resin is preferably about 0.5% by mass to about 15% by mass, more preferably about 1% by mass to about 10% by mass, based on the total mass of the powder coating. If the content of the thermoplastic resin is within the above range, a barbed wire 1 having better durability can be obtained.

[0047] In addition to the above components, the powder coating may contain other components such as additives such as a curing accelerator or curing catalyst, a surface conditioner, a plasticizer, an ultraviolet absorber, an antioxidant, a pigment dispersant, and an impact resistance improver.

[0048] The powder coating material described above can be obtained, for example, as follows. That is, the inorganic particles, thermosetting resin, curing agent, and other additives used as necessary are mixed uniformly by a mixer such as a Henschel mixer, a super mixer, a ball mill, or a Banbury mixer. Next, the mixture obtained is melt-kneaded by a kneader such as an extruder or a heat roll in a temperature range in which the curing reaction of the thermosetting resin does not occur, and other components are uniformly dispersed in the molten thermosetting resin. Thereafter, the mixture obtained is molded into pellets. The obtained pellets are pulverized by an impact pulverizer such as a hammer mill, an airflow pulverizer such as a jet mill, or the like, and then classified to obtain the powder coating material described above.

[0049] In addition, in order to achieve sufficient corrosion resistance and inconspicuousness at night while keeping the manufacturing costs of the barbed wire 1 low, the thickness of the powder paint layer is preferably greater than or equal to 100 μm and greater than or equal to 150 μm, and more preferably greater than or equal to 100 μm and greater than or equal to 120 μm.

[0050] Furthermore, when the thickness of the powder coating layer is T1 [μm] and the thickness of the plating layer is T2 [μm], it is preferable that the relationship of 1.25≦T1 / T2≦8 is satisfied, it is more preferable that the relationship of 1.5≦T1 / T2≦6 is satisfied, and it is even more preferable that the relationship of 2≦T1 / T2≦4 is satisfied. When the thicknesses of the powder coating layer and the plating layer satisfy the above conditions, the durability of the plating layer and the powder coating layer as a whole is increased, and the product life of the barbed wire 1 can be extended.

[0051] As described above, the barbed wire 1 is wound in a spiral shape to form a cylindrical shape. The diameter of the wound wire of the barbed wire 1 can be changed as appropriate depending on the site where it is laid, but can be, for example, about 500 to 1200 mm. The length of the wound iron wire when stretched in a direction perpendicular to the winding direction is not particularly limited, but may be, for example, about 10 to 15 m. The weight of the barbed wire 1 having a diameter of 600 mm and a length of 13 m when stretched out is about 11.5 kg. The weight of the barbed wire 1 having a diameter of 1000 mm and a length of 13 m when stretched out is about 19 kg.

[0052] 2. How barbed wire is made Next, a method for manufacturing the above-mentioned barbed wire 1 will be described. The method for manufacturing the barbed wire 1 includes a step (first step) of preparing a base material 10 by attaching a number of barbs 3 to an iron or steel wire 2, a step (second step) of forming a zinc-containing plating layer on the surface of the base material 10, and a step (third step) of forming a powder paint layer on the plating layer to obtain the barbed wire 1. Each step will be described in detail below.

[0053] (First step) The first step is to prepare a base material 10 by attaching a plurality of barbs 3 to a wire 2. Here, the step of preparing the base material 10 will be described with reference to FIG. Figure 2 is a diagram for explaining the process of preparing a base material, where Figure 2(a) is a diagram showing a barbed plate material on which barbs have been formed, Figure 2(b) is a diagram showing a state in which a wire has been placed in the center of the barbed plate material, and Figure 2(c) is a diagram showing the state in which the barbed plate material has been processed from the state in Figure 2(b) so that the wire is wrapped in it.

[0054] First, a long plate material is prepared for forming the barbs 3. Next, the plate material is pressed using a press cutting machine to cut off the portions of the plate material other than the portions that will become the barbs 3 on both edges. After that, the plate material is cut so that the portions that will become the barbs 3 conform to the specifications of a specified laser blade, thereby obtaining a plate material 30 with barbs as shown in Fig. 2(a). The width of the prepared plate material can be changed appropriately according to the specifications of the barbed members 3 to be formed, but when the diameter of the wire 2 is about 1.0 to 4.0 mm, the width can be about 15 to 25 mm. The barbed plate material 30 thus formed is wound on a tape recoiler and stored in preparation for assembly with the wire 2.

[0055] Next, the wire 2 wound into a coil shape and the barbed plate material 30 wound around a tape recoiler are prepared, and the barbed plate material 30 is pulled out from the tape recoiler while the wire 2 is pulled out at the same time. The wire 2 is placed so that it is positioned at the center of the barbed plate material 30, as shown in Figure 2(b). The distance between both edges 31 of the barbed plate material 30 (the distance between both edges 31 of the barbed plate material 30 in the area where the barbs 3 are not formed) is configured to be larger than the wire diameter of the wire 2. Specifically, the distance between both edges 31 of the barbed plate material 30 is preferably about 2.0 to 2.8 times, and more preferably about 2.2 to 2.5 times, the wire diameter of the wire 2. If the distance between both edges 31 of the barbed plate material 30 is within the above range, even if the wire 2 is slightly misaligned from the center of the barbed plate material 30, a base material 10 with stable mechanical properties such as durability can be obtained.

[0056] In this state, the wire 2 and the barbed plate material 30 are passed through an assembly molding machine, whereby both edges 31 of the barbed plate material 30 are processed to wrap around and secure the wire 2 (Figure 2(c)). Through this processing, the base material 10 for the barbed wire 1 is formed. In addition, when the wire 2 is wrapped in the barbed plate material 30, it is preferable that the distance between the opposing edges 31 of the barbed plate material 30 is smaller than the wire diameter of the wire 2. In other words, it is preferable that a part of the wire 2 is exposed to the outside from the barbed plate material 30 in the base material 10. By configuring it in this way, the mechanical properties such as durability are more stable than in a base material 10 in which the wire 2 is completely covered by the barbed plate material 30.

[0057] The base material 10 thus formed is wound in a spiral shape by using a bobbin machine, stretched and formed into a cylindrical shape, and cut to have the same length and diameter as the barbed wire 1 that will be the product. That is, in this embodiment, the base material 10 prepared in the first step has the same outer shape as the barbed wire 1 that will be the product, and the base material 10 is not cut in the subsequent steps.

[0058] (Second step) The second step is to form a plating layer containing zinc on the surface of the base material 10. The plating layer is formed by a plating process such as hot-dip plating or electroplating. In the hot-dip plating process, the base material 10 is first immersed in molten zinc or zinc alloy. The base material 10 is then pulled out and left at room temperature to form a plating layer on the surface of the base material 10. In the electroplating process, the base material 10 is first immersed in a plating solution of zinc or zinc alloy. Then, a direct current is passed through the plating solution to deposit a plating layer on the surface of the base material 10.

[0059] In the hot-dip plating process, the amount of plating material attached to the surface of the base material 10 is 400 g / m 2 In the electroplating process, the amount of plating material attached to the surface of the base material 10 is 120 to 200 g / m 2 The thickness of the plating layer is about 15 to 30 μm. Therefore, a hot-dip plating process or an electroplating process is selected to form a plating layer on the surface of the base material 10 so as to obtain a plating layer of a desired thickness.

[0060] (Third step) The third step is to form a powder paint layer made of powder paint on the plating layer of the base material 10 to obtain the barbed wire 1. The powder coating layer is formed by powder coating processes such as electrostatic powder coating and fluidized bed coating. In the electrostatic powder coating process, electrically charged powder paint is discharged toward the base material 10. This electrostatically attaches the powder paint to the plating layer of the base material 10 to form a powder paint layer. In the fluidized bed process, a tank filled with fluidized powder paint that has been stirred up by compressed air and a heated base material 10 are first prepared. The heated base material 10 is then placed in the tank filled with the powder paint. This is a method of forming a powder paint layer on the plating layer of the base material 10. Of these treatments, it is preferable to use electrostatic powder coating, which can reduce the amount of powder paint used.

[0061] The electrostatic powder coating process includes a process of spraying the electrically charged powder paint onto the plating layer to adhere (apply) the powder paint onto the plating layer (hereinafter also referred to as the "application process"), and a process of heating the powder paint on the plating layer to form a powder paint layer (hereinafter also referred to as the "baking process"). Each process will be described below.

[0062] <Painting process> In the coating process, a charged powder coating material is sprayed and electrostatically adheres (coats) the powder coating material to the plating layer to form an adhesion layer. Specifically, in the coating process, for example, with an electrostatic field formed between the discharge port of the electrostatic powder sprayer and the plating layer (conductive surface) of the base material 10, charged powder paint is sprayed from the discharge port of the electrostatic powder sprayer, and the powder paint is electrostatically attached to the plating layer of the base material 10 to coat the attachment layer. For example, when a voltage is applied to the plating layer of the grounded base material 10 as the anode and the electrostatic powder sprayer as the cathode, an electrostatic field (electrostatic field) is formed between the two poles. When the powder is sprayed in this state, the powder becomes charged. The charged powder paint flies from the discharge port to the plating layer and electrostatically attaches to the plating layer. This forms a film of the powder paint.

[0063] In this way, in electrostatic powder coating, the powder paint and the plating layer of the object to be coated are charged with opposite polarities. Therefore, even if the shape of the base material 10 is complex, the entire base material 10 can be covered with a film of powder paint via the plating layer. For example, the base of the barbed body 3 is a part that is prone to uneven painting in general painting processes, but by using electrostatic powder coating, uneven painting does not occur even in such a small part. In addition, during the process of forming a powder coating film, the thicker the coating, the weaker its polarity becomes. By utilizing this property, the thinner the coating, the easier it is for the powder coating to adhere, resulting in a uniform coating thickness throughout the entire powder coating layer. Due to the above-mentioned action and effect, the obtained barbed wire 1 has the property that the entirety thereof has excellent corrosion resistance.

[0064] As the electrostatic powder sprayer, for example, a corona gun (a sprayer that sprays powder paint charged by corona discharge), a tribo gun (a sprayer that sprays powder paint by frictional charging), etc. Of these, it is preferable to use a corona gun since it can be used regardless of the material of the paint.

[0065] The corona gun is equipped with a corona electrode at its discharge port. By applying a voltage from an external power source to this corona electrode, an electrostatic field is formed between the corona gun (the corona gun's discharge port) and the plating layer. At the same time, a corona discharge is generated from the corona electrode. The powder paint is charged by ions generated by this corona discharge.

[0066] The voltage applied to the corona electrode can be appropriately changed to obtain the desired thickness of the powder coating layer, but is preferably about 30 to 90 kV, and more preferably about 45 to 85 kV. If the voltage applied to the corona electrode is within the above range, coating unevenness does not occur even in small locations such as the bases of the barbs 3. As a result, a powder coating layer having a uniform thickness of 100 μm or more can be formed more stably and in a short time.

[0067] The amount of powder coating applied to the plating layer of the base material 10 is 100 g / m 2 This allows the thickness of the finally formed powder coating layer to be 100 μm or more.

[0068] <Baking process> In the baking process, the powder paint on the plating layer is heated to form the powder paint layer. Specifically, the particles that make up the powder paint film are melted and hardened by heating, thereby forming the powder paint film. The heating temperature (baking temperature) is selected depending on the type of powder coating. For example, the heating temperature is preferably about 200 to 285° C., more preferably about 220 to 280° C., and even more preferably about 240 to 270° C. The heating time (baking time) is adjusted depending on the heating temperature, and can be, for example, about 10 to 30 minutes.

[0069] Through the above steps, the barbed wire 1 is obtained. After the second step, or after the third step, or after each of the second and third steps, various degreasing treatments and foreign matter removal treatments may be carried out as necessary. The barbed wire and the method for manufacturing barbed wire of the present invention have been described above based on the illustrated embodiment, but the present invention is not limited to this, and each component can be replaced with any component that can perform a similar function, or any component can be added. EXAMPLES

[0070] Next, a specific embodiment of the present invention will be described. 1. Barbed wire manufacturing (Example) <First step> A long plate material with a width of 18 mm and a thickness of 0.5 mm was prepared as the plate material for forming the barbed bodies. This plate material was pressed using a press cutter to cut off the parts other than the parts that would become the barbed bodies on both edges of the plate material. The plate material was then cut so that the parts that would become the barbed bodies had blades of 10 mm and blade spacing of 25 mm. This resulted in a plate material with barbed bodies as shown in Figure 2(a). The resulting plate material with barbed bodies was wound on a tape recoiler.

[0071] Next, a coiled wire with a wire diameter of 2.5 mm was prepared together with the barbed plate material wound around the tape recoiler. As the barbed plate material was pulled out of the tape recoiler, the wire was also pulled out at the same time, and the wire was placed so that it was located in the center of the barbed plate material, as shown in Figure 2(b). In this state, the wire and the barbed plate were passed through an assembly molding machine so that both edges of the barbed plate wrapped around and fixed the wire (Figure 2(c). This process formed the barbed wire base material. The blank thus formed was wound into a spiral shape using a bobbin machine, stretched to form a cylindrical shape, and cut to the same length and diameter as the final barbed wire.

[0072] <Second step> Next, the base material was immersed in a tank filled with molten zinc and heated to 450°C. It was then pulled out and left at room temperature to form a 70μm-thick plating layer on the surface of the base material.

[0073] <Third process> Next, prior to forming a powder coating layer made of a powder coating on the plating layer, a powder coating having the following composition was prepared. ·Quartz (average particle size: 20nm): 1% by mass Polyethylene: 5% by weight Barium sulfate (average particle size: 50 nm): 15% by mass ·Limestone (average particle size: 50nm): 15% by mass Triglycidyl isocyanurate: 2% by mass Thermosetting polyester resin: 62% by mass The powder coating was obtained by stirring and mixing the above materials in a ball mill.

[0074] Next, the base material on which the plating layer was formed was fixed to a dedicated jig connected to earth for electrostatic powder coating. Next, a corona gun was prepared as an electrostatic powder sprayer, and the powder paint having the above composition was filled in. Then, a voltage of 70 kV was applied from an external power source to the corona electrode of the corona gun, and electrostatic powder coating was performed for 100 minutes at 25°C, in which the powder paint was discharged from the discharge port of the corona gun onto the plating layer. As a result, a film of the powder paint was formed on the plating layer.

[0075] Next, the base material with the powder paint film formed thereon was heated at 270°C for 20 minutes to form a powder paint layer with a thickness of 110 µm on the plating layer, thereby obtaining barbed wire.

[0076] 2. Salt spray test evaluation The barbed wire obtained in the above example was placed in a test tank. In accordance with the KS standard: KS D 9502, the temperature in the test tank was kept at 35°C, and a 5% NaOH aqueous solution was sprayed onto the barbed wire for 1000 consecutive hours using a sprayer. As a result, it was confirmed that no red rust was formed on the barbed wire of the embodiment after 1000 hours had passed.

Claims

1. A barbed wire used in an intrusion prevention fence, A base material having an iron or steel wire and a plurality of barbs attached to the wire; a zinc-containing plating layer formed on the surface of the base material; A powder coating layer formed on the plating layer, The powder coating layer contains inorganic particles and a thermosetting resin, A barbed wire characterized in that the powder coating layer has a thickness of 100 μm or more.

2. 2. The barbed wire according to claim 1, wherein the plating layer has a thickness of 20 μm or more and 80 μm or less.

3. 3. The barbed wire according to claim 1 or 2, wherein when the thickness of the powder coating layer is T1 [μm] and the thickness of the plating layer is T2 [μm], the relationship of 1.25≦T1 / T2≦8 is satisfied.

4. 2. The barbed wire of claim 1, wherein the inorganic particles include silica, barium sulfate and calcium carbonate.

5. 2. The barbed wire of claim 1, wherein the thermosetting resin comprises a thermosetting polyester resin.

6. A method for manufacturing barbed wire for use in an intrusion prevention fence, comprising the steps of: preparing a base material by attaching a plurality of barbs to an iron or steel wire; forming a zinc-containing plating layer on a surface of the base material; and forming a powder coating layer on the plating layer to obtain the barbed wire. The step of forming the powder coating layer includes: preparing a powder coating; spraying the powder paint onto the plating layer to adhere the powder paint onto the plating layer; and heating the powder coating to form the powder coating layer. The step of applying the powder paint includes a step of spraying the powder paint onto the plating layer using an electrostatic powder sprayer having a discharge port and a corona electrode at the discharge port; applying a voltage to the corona electrode of the electrostatic powder sprayer to generate an electric field between the electrostatic powder sprayer and the plating layer, thereby charging the powder paint; A method for manufacturing barbed wire, characterized in that the powder paint layer has a thickness of 100 μm or more.

7. The method for manufacturing barbed wire according to claim 6, wherein the step of forming the powder coating layer is carried out at 200 to 285°C.

8. The method for manufacturing barbed wire according to claim 6, wherein the step of preparing the base material includes the steps of preparing a long plate material on which the barbs are formed, and wrapping and fixing the wire with the plate material.

9. The base material is formed into a cylindrical shape by winding the wire in a spiral shape, The method for manufacturing barbed wire according to any one of claims 6 to 8, wherein the step of forming the plating layer and the step of forming the powder coating layer are performed on the cylindrical base material.

10. The barbed wire is wound into a cylindrical shape, The length of the cylindrical base material is the same as the length of the cylindrical barbed wire; The method for manufacturing barbed wire according to claim 9, wherein the diameter of the cylindrical base material is the same as the diameter of the cylindrical barbed wire.

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