Electric resistance layer

Abstract

To provide means for preventing an isolation layer from separating or cracking, and also for surely insulating with almost no pinholes, by a simple configuration.SOLUTION: An electric resistance layer 50 includes a second phosphate layer 40 obtained through a phosphate conversion treatment to a metal plating part 30 applied to a conductive part 22 present in a first phosphate layer 20 disposed on a surface of a base material 10. With the phosphate layer formed over an entirety of the base material 10, the conductive part 22 such as a pinhole is eliminated, and an electric resistance layer having insulation properties can be formed, not only with high electrical resistance but also with high dielectric strength. The electric resistance layer 50 can also be prevented from separating or cracking against the base material 10, and a degradation under a high-temperature and high-humidity environment or the like can also be prevented.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an electrical resistance layer formed on the surface of a base material. [Background technology]

[0002] Conventionally, a multilayer printed wiring board formed by alternately laminating conductor layers and insulating layers has been proposed (see, for example, Patent Document 1). The insulating layer of this multilayer printed wiring board is formed by stacking a thermosetting resin layer and a liquid crystal polymer resin layer.

[0003] Also, a thin metal package has been proposed in which an insulating layer is formed by directly changing the surface of the base metal constituting the base member through a chemical reaction, and pattern electrodes are formed on the insulating layer (see, for example, Patent Document 2). The insulating layer here is made of insulating metal compounds such as metal oxides and metal hydroxides that are generated directly from the base metal, and is an anodic oxide film or the like provided by anodizing the base member. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-216841 A [Patent Document 2] JP 2013-128037 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, conventional insulating layers have various problems. For example, an insulating layer made of a resin has a different thermal expansion coefficient from that of a conductor layer, which may cause problems such as peeling of the insulating layer from the conductor layer and the occurrence of cracks. In addition, since the insulating layer made of resin does not have sufficient heat resistance or weather resistance, it deteriorates quickly due to repeated thermal expansion and contraction, wetting and drying in high temperature and humid environments, etc., which may cause peeling of the insulating layer from the conductor layer and the occurrence of cracks.

[0006] Also, as in Patent Document 2, when an insulating film is formed by chemically reacting the surface of a base metal, defects such as peeling and cracking due to differences in thermal expansion coefficients, and peeling and cracking due to heat resistance and weather resistance can be prevented to a certain extent, but the thickness of the insulating film is uneven, and insulation breakdown is likely to occur in the thin parts. In addition, the insulating film has many so-called pinholes that become conductive parts along with the thin parts. Although only a very small current can flow through each of these conductive parts, since there are many of them, the total value of the small currents as a whole of the insulating film becomes the current flowing through the insulating film. Therefore, if a conductive layer or conductive pattern is formed on an insulating film having such defects, electrons will flow between the conductive layer and the conductive base material, causing electricity to flow, and the circuit will not function normally. Therefore, there is a problem that, although it is an insulating film, a relatively large current flows through it, making it very difficult to use it as an insulating film.

[0007] The present invention was made through intensive research by the inventors in consideration of the above problems, and has an object to provide an electrical resistance layer with a simple structure that prevents peeling or cracking of the insulating layer and is reliably insulated. [Means for solving the problem]

[0008] The electrical resistance layer of one embodiment of the present invention has a second phosphate layer formed by phosphate treatment of a metal plating portion applied to a conductive portion present in a first phosphate layer provided on the surface of a base material. The electrical resistance layer according to another embodiment of the present invention comprises a metal oxide formed by oxidizing a metal plating applied to a conductive portion present in a phosphate layer provided on the surface of a base material.

[0009] The electrical resistance layer has an appropriate resistance value obtained by subjecting the conductive portion remaining in the second phosphate layer to metal plating and the phosphate treatment in at least one stage.

[0010] The electrically resistive layer may include a first phosphate layer selected from the group consisting of a manganese phosphate layer, a zinc manganese phosphate layer, and a zinc phosphate layer.

[0011] The electrically resistive layer, the first phosphate layer and the second phosphate layer, constitute an insulating layer that insulates the entire surface of the base material.

[0012] The electrically resistive layer comprises a conductive layer formed on the insulating layer.

[0013] The electrical resistance layer has a withstand voltage performance exceeding a predetermined voltage applied to the conductive layer by the insulating layer.

[0014] The electrically resistive layer is such that the conductive layer includes a conductive pattern. Effect of the Invention

[0015] According to the present invention, it is possible to provide an electrical resistance layer that is reliably insulated and prevents the occurrence of peeling or cracking of the insulating layer, by a simple manufacturing method. [Brief description of the drawings]

[0016] [Figure 1] 1 is a diagram showing a base material to which an insulating layer forming method according to an embodiment of the present invention is applied; [Diagram 2] 4 is a diagram showing a base material after a second step in the insulating layer forming method according to the embodiment. FIG. [Diagram 3] 4 is a diagram showing a base material after a third step in the insulating layer forming method according to the embodiment. FIG. [Figure 4] FIG. 13 is a diagram showing a phosphate layer when an oxidation treatment is performed in the third step. [Diagram 5] FIG. 2 is a diagram showing a base material on which a metal plating portion is formed in a preliminary step. [Figure 6] FIG. 13 shows a conductive portion that exists after the third process. [Figure 7] FIG. 13 shows the formation of a phosphate layer when the second and third steps are carried out again. [Figure 8] FIG. 2 is a diagram showing an iron-plated portion formed by dry plating. [Figure 9]FIG. 2 is a diagram showing a phosphate layer formed on an iron-plated portion. [Figure 10] FIG. 2 is a diagram showing a conductive layer formed on an insulating layer. [Figure 11] FIG. 2 is a diagram showing a measurement block. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The following describes an example of an embodiment of the method for forming an insulating layer according to the present invention, which is a method for forming an insulating layer by self-selective blocking of fine conductive parts. In this embodiment, the target base material for forming the insulating layer is a metal that is a good conductor, but the present invention is not limited to this, and the method can be appropriately set to an electrically resistive base material or an electrically insulating base material.

[0018] The method for forming an insulating layer of the present invention includes a first step of forming a high resistance layer on a base material by surface treatment, a second step of forming a metal plating portion capable of forming a high resistance layer on the base material that has been subjected to the first step, and then a further step of forming a high resistance layer. Conventionally, simply forming a high resistance layer on a base material inevitably results in the formation of fine conductive portions such as so-called pinholes through which electricity can pass, portions where the high resistance layer is thin, and portions in which fine conductors exist continuously or intermittently in the high resistance layer and can pass electricity when a voltage is applied, resulting in insufficient insulation. However, the present invention reduces the fine conductive portions by blocking the fine conductive portions with metal plating and then performs a process of forming a high resistance layer there, thereby realizing high insulation.

[0019] The first step of the present invention is to form a high resistance layer on the base material. Examples of the step of forming a high resistance layer include chemical conversion treatment and phosphate conversion treatment in which a metal oxide layer is formed on the surface of the base material using a rust accelerator and / or rust-inducing agent containing an acidic liquid such as hydrochloric acid or salt water.

[0020] The method for forming an insulating layer using a phosphating chemical conversion treatment is a method comprising at least the first to third steps. That is, the method comprises the first step of performing a phosphating chemical conversion treatment on a base material, the second step of forming a metal plated portion self-selectively on the fine conductive portions present in the phosphating layer formed in the first step to block them, and the third step of performing a phosphating chemical conversion treatment on the metal plated portion to insulate the metal plated portion. In the second step, iron is precipitated mainly around the conductive portions (fine conductive portions) remaining in the phosphating layer described below, preferably only in the conductive portions. As a result, the iron plated portion is formed so as to select only the conductive portions in the phosphating layer, and this is referred to as self-selective blocking of fine conductive portions by the iron plated portion.

[0021] In addition, since the base material is subjected to phosphating treatment, the base material here is a metal that can be subjected to phosphating treatment, such as iron or an iron alloy, tin or a tin alloy, zinc or a zinc alloy, nickel or a nickel alloy, aluminum or an aluminum alloy, etc.

[0022] 1 shows a base material 10 to which the insulating layer forming method according to this embodiment is applied, with (a) showing the base material before a first step and (b) showing the base material after the first step. The first step is a step of performing a phosphating treatment to form a high resistance layer (a layer having insulating properties) having high electrical resistivity on the base material 10. The phosphating treatment to form an insulating layer uses a phosphating treatment solution that generates phosphates such as zinc phosphate, manganese phosphate, and zinc manganese phosphate on the surface of the base material.

[0023] The first step may include a degreasing step, a water-washing step, a water-washing step after the phosphating step, a pure water-washing step, a drying step, and the like in addition to the phosphating step, and these steps are carried out by using known methods.

[0024] In the phosphating process, the surface of the base material is brought into contact with the phosphating solution by spraying or immersion, forming a phosphating layer 20 on the surface of the base material 10 as shown in FIG.

[0025] The phosphating treatment can be carried out, for example, by immersing the material in a phosphating treatment solution, in which case the temperature of the solution is preferably 95°C or higher. Another method is to carry out cathodic electrolysis in the phosphating treatment solution. In this case, the current density is 1 to 100 A / dm 2 It is preferable that the liquid temperature is 90°C or less. 2 If the current is less than 100 A / dm, the crystals that form the appropriate phosphate chloride layer (called phosphate crystals) will not be formed. 2 If the current density exceeds this value, hydrogen gas will be generated intensively on the surface of the base material 10 during the cathodic electrolytic treatment, making it difficult for a phosphate layer to grow on the surface of the base material 10. In any case, the treatment time is preferably 5 to 60 minutes, and more preferably 10 to 20 minutes.

[0026] The phosphating chemical treatment solution contains phosphate ions as an essential component, and at least one metal ion selected from the group consisting of magnesium ions, aluminum ions, calcium ions, manganese ions, iron ions, cobalt ions, nickel ions, copper ions, and zinc ions. The phosphating chemical treatment solution preferably contains 3 to 50 g / L of phosphate ions, for example. If the content is less than 3 g / L, the rate at which the phosphating layer is formed slows down. If the content of phosphate ions exceeds 50 g / L, the concentration becomes high, which is a disadvantage in that more phosphate ions are carried away.

[0027] Nitrate ions may be added to the phosphating chemical treatment solution to improve its stability and promote polarization in cathodic electrolysis, and nitrite ions, hydrogen peroxide, and chlorate ions may be added as oxidation promoters. Carbon, stainless steel, platinum, titanium alloys, titanium-platinum coated alloys, etc. are used as electrodes for electrolysis.

[0028] In addition, a surface conditioning step may be performed before the phosphating conversion treatment step, which activates the surface of the base material and creates nuclei for phosphate crystal precipitation. The surface conditioner used when performing the surface conditioning step is appropriately selected depending on the phosphate, and may be any of liquid, gel, fluid, etc. According to the surface conditioning step, for example, a component that becomes the nucleus of the phosphate crystal adheres to the surface of the base material 10. Therefore, the phosphate crystals are generated and grow from the component that becomes the nucleus. Furthermore, by performing the surface conditioning step, the phosphate crystals become dense crystals, and the conversion reaction is more likely to occur. Therefore, the processing time of the conversion treatment step is shortened compared to the case where the surface conditioning step is not performed.

[0029] The phosphate layer 20 formed on the surface of the base material 10 has many conductive parts 22 through which extremely small currents flow, such as thin parts that are fine conductive parts and pinholes, similar to the insulating layer formed by chemically reacting the surface of the base metal in Patent Document 2. Such conductive parts 22 are filled with the phosphate layer and insulated by carrying out the second and third steps described below.

[0030] Next, the second step performed after the first step will be described. Fig. 2 is a diagram showing the base material 10 after the second step in the method for forming an insulating layer according to this embodiment. The second step is a step of forming an iron-plated portion as an upper layer of the phosphate layer 20. Here, the formation of an iron-plated portion will be described, but the present invention is not limited to this. Any metal-plated portion may be used as long as it has good adhesion to a phosphate layer such as a zinc-plated portion, a tin-plated portion, or a nickel-plated portion, and is mainly composed of a material that can be subjected to a phosphate chemical treatment in the third step described below.

[0031] Furthermore, the iron-plated portion may be any plating containing at least iron as a main component, such as a pure iron-plated portion, an iron-carbon alloy-plated portion, an iron-based alloy-plated portion (Fe-W, Fe-Ni, Fe-P, Fe-Zn, Fe-Ni-Mo, Fe-Co, Fe-Cr, Fe-Cr-Ni, etc.), etc.

[0032] Such iron-plated portions can be produced by various plating methods, such as dry plating methods such as physical vapor deposition (PVD) and chemical vapor deposition (CVD), hot-dip plating, and thermal spraying. However, it is preferable to use wet plating methods such as electrolytic plating or electroless plating, which will be described later.

[0033] Formation of the iron-plated portion by electrolytic plating can be carried out by a known method, for example, a sulfate bath or a borofluoride bath. When electrolytic plating is carried out, an anode is immersed in a plating solution, and at the same time, a base material 10 (cathode) is immersed so as to face the anode with a gap therebetween.

[0034] The anode is an iron metal plate. For example, two anodes may be prepared and immersed in the plating solution so that they face each other with a gap between them. In this case, it is preferable to immerse the base material 10 in the plating solution between the two anodes so that it faces each anode with a gap between them.

[0035] The temperature of the plating solution is preferably in the range of 20°C to 38°C when a sulfate bath is used. While maintaining the temperature of the plating solution within a predetermined range, electroplating is performed at a constant current to form an iron-plated portion. The current density is, for example, 2.5 to 10 A / dm when a sulfate bath is used. 2 That would be good.

[0036] By electroplating using the above method, iron is precipitated on the conductive parts 22 in the phosphate layer 20 to form the iron-plated parts 30, as shown in Fig. 2. That is, since electroplating forms plating on parts that are electrically conductive, the iron-plated parts 30 are formed around the conductive parts 22 through which current flows in fine conductive parts in the insulating phosphate layer 20 (for example, pinholes or parts where the layer is thin and dielectric breakdown is likely to occur).

[0037] Next, the third step will be described. Fig. 3 is a diagram showing the base material 10 after the third step in the method for forming an insulating layer according to this embodiment. The third step is a step of forming a second phosphate layer 40 on the iron-plated portion 30.

[0038] The second phosphate layer 40 here can be formed by carrying out a phosphating chemical treatment similar to that in the first step. The second phosphate layer 40 is formed as an upper layer of the iron-plated portion 30. That is, the phosphating chemical treatment is almost ineffective against the already formed phosphating layer 20, and almost no phosphate crystals precipitate. In contrast, the phosphating chemical treatment is effective against the iron-plated portion 30, and as shown in FIG. 3(a), phosphate crystals precipitate on the surface of the portion where the iron-plated portion 30 is formed. As the phosphating chemical treatment progresses, the second phosphate layer 40 is formed so as to cover the portion where the iron-plated portion 30 was formed, as shown in FIG. 3(b).

[0039] Therefore, phosphate crystals precipitate in the areas that were previously the conductive portions 22 of the phosphate layer 20 formed in the first step and where the iron-plated portions 30 are formed, forming a second phosphate layer 40 that spontaneously and selectively fills in the areas that were previously the conductive portions 22 of the phosphate layer 20 formed in the first step. This causes the conductive portions 22 of the phosphate layer 20 to be blocked by the second phosphate layer 40, and as a result, the entire surface of the base material 10 can be covered with an insulating layer made of a substantially uniform phosphate layer with almost no conductive portions 22.

[0040] In addition, since the insulating layer of the present invention has almost no conductive portions 22, it can be said to be a surface insulating layer in which the phosphate layer is insulated throughout.

[0041] The second phosphating layer 40 does not necessarily have to be the same as the phosphating treatment in the first step, and may be a different phosphating treatment. For example, a treatment to form a manganese phosphate layer may be carried out as the phosphating treatment in the first step, and a treatment to form a zinc-manganese phosphate layer may be carried out as the phosphating treatment in the third step.

[0042] As described above, according to the method for forming an insulating layer of this embodiment, the base material is subjected to surface treatment in the order of phosphating, electroplating to form an iron-plated portion, and phosphating. This allows the phosphating layer to fill (close) pinholes and thin conductive parts that occur in the phosphating layer formed first. This allows the formation of an insulating layer with extremely high insulating properties, and the surface of the base material to be highly insulated. Moreover, since this insulating layer is not formed of resin, it is possible to prevent peeling or cracking of the insulating layer due to the difference in thermal expansion coefficient between the base material and the insulating layer, and to suppress the decrease in strength due to deterioration under high temperature, high humidity, and other environments.

[0043] In the second step, the iron-plated portion may be formed by electroless plating. In this case, a plating solution for autocatalytic (reduction) electroless plating is used, and the temperature of the plating solution is set to 70 to 100° C., preferably 85 to 95° C. This also allows the iron-plated portion to be formed in the conductive portion that has become a pinhole, and by further performing the third step, the conductive portion that has become a pinhole can be sealed with a phosphate layer, and the surface of the base material can be covered with the phosphate layer as an insulating layer.

[0044] In addition, it is desirable to set the thickness of the iron plating to be equal to or less than the limit of the thickness that the phosphate layer formed in the subsequent third step can achieve, because if the thickness of the iron plating is too thick, iron molecules of the iron plating that exceed the layer thickness that the phosphate layer can achieve in the third step will remain without being phosphated, and the remaining iron molecules may form fine conductive parts.

[0045] Of course, the thickness of this iron plating can be controlled by time control. The iron plating time is, for example, 1 to 60 minutes, preferably 2 to 10 minutes. However, the suitable iron plating time can vary depending on the size and number of fine conductive parts generated in the phosphate chloride layer generated in the first process.

[0046] In the above embodiment, the phosphating process is described as being performed in the first and third steps, but an oxidation process may be used if a high resistance layer can be formed. That is, the phosphating process is performed in the first step, and the oxidation process is performed in the third step. FIG. 4 shows the phosphating layer when the oxidation process is performed in the third step. When the phosphating layer 20 has conductive parts 22 in which iron plating parts 30 are formed scattered as shown in FIG. 4(a), the iron plating parts 30 are oxidized by the oxidation process. As a result, as shown in FIG. 4(b), the iron plating parts become metal oxides 42 equivalent to a high resistance layer, like the phosphating layer. Therefore, the surface of the iron plating parts formed in the second step is oxidized to metal oxides 42, and as a result, it becomes possible to insulate the conductive parts 22.

[0047] In the third step, an oxidation treatment may be further performed after the phosphating treatment. The oxidation treatment may be performed by any of a variety of methods, such as by subjecting the base material 10 to an anodized layer formation treatment, by heating the base material 10 under high-concentration oxygen, or by immersing the base material 10 in an oxidation (accelerated) treatment solution.

[0048] In addition, in order to perform the phosphating treatment in the first and third steps, the case where the base material is a metal that can be phosphating treated has been described as an example. However, when the base material is a metal that is difficult to phosphating (e.g., copper or some stainless steels), a process of forming a metal plating portion 15 for which phosphating treatment is effective may be performed on the base material 10 as shown in FIG. 5(a) as a preliminary process before the first step. In this way, by performing the first step, a phosphating layer 20 can be formed on the metal plating portion 15 as shown in FIG. 5(b). Next, by performing the second step, an iron plating portion 30 can be formed on the phosphating layer 20 as shown in FIG. 5(c). Then, by performing the third step, a phosphating layer 40 can be formed as an upper layer of the iron plating portion 30 as shown in FIG. 5(d). As a result, even if the base material 10 is difficult to phosphating, by forming the metal plating portion 15 directly on the base material 10, an insulating layer can be formed by the above-mentioned first to third steps. Of course, the base material is not limited to metal, but may be resin, ceramic, glass, etc. In this case, a layer that can be subjected to conductive surface modification, treatment, plating, etc., i.e., phosphate chemical conversion treatment, is formed in advance on the surface of the base material.

[0049] Therefore, the method for forming an insulating layer according to the present invention can be applied even to a base material that is difficult to treat with a phosphate chemical conversion treatment. The metal-plated portion to be applied to the preliminary step can be, for example, an iron-plated portion, a tin-plated portion, a zinc-plated portion, or the like, and can be appropriately selected.

[0050] In addition, the plating method in the preliminary process is not particularly limited and can be appropriately selected from dry plating, wet plating, hot-dip plating, etc., but it is preferable to use a method that can form a metal plating portion over the entire base material, such as a physical vapor deposition method, a chemical vapor deposition method, or an electroless plating method using an ionic liquid.

[0051] In the above-described embodiment, the second and third steps may be repeated again after the third step. In this way, if the conductive portion 22 exists even after the third step as shown in Fig. 6, the second step can be performed again to form a metal plating portion on the conductive portion 22. The metal plating portion here is an iron plating portion as in the initial second step, but it may of course be a different metal plating portion, such as a tin plating portion, a zinc plating portion, or a nickel plating portion.

[0052] That is, when the second step is performed again after the third step, an iron-plated portion 35 is formed on the remaining conductive portion, as shown in Fig. 7(a). When the third step is performed again, the iron-plated portion 35 dissolves and a phosphate layer 45 is formed as shown in Fig. 7(b), and as a result, a phosphate layer 45 is formed on the conductive portion 22, making it possible to form an insulating layer with higher insulating properties. Note that the number of times the second step and the third step are repeated is not particularly limited, but by increasing the number of times, the conductive portion 22 can be reduced and the thickness of the layer formed on the base material can also be increased.

[0053] Needless to say, the iron-plated portion in the second step may be formed by dry plating. In that case, the iron-plated portion is formed over the entire base material so as to cover almost the entire phosphate layer including the conductive portion 22, as shown in FIG.

[0054] Next, when the third step is carried out, the surface of the iron-plated portion dissolves and phosphate crystals are precipitated to form a phosphate layer, as shown in Figure 9. At this time, the iron-plated portion may not completely dissolve, but may remain on the originally established phosphate layer, and a new phosphate layer may be formed on top of it. In other words, the phosphate layer may be locally laminated on either side of the iron-plated portion.

[0055] Furthermore, fine conductive parts may also be formed in the phosphate layer formed in the third step, but there is a low possibility that such fine conductive parts will communicate with the fine conductive parts of the phosphate layer formed in the first step. This is because, if the thickness of the iron plating part is set to be equal to or less than the upper limit thickness of the phosphate layer that can be formed by the subsequent phosphating treatment, most of the iron components formed on the phosphate layer formed in advance by the iron plating will be replaced by the phosphate layer, and most of the iron components, which are conductive components, will disappear. In other words, by stacking the phosphate layers through iron plating in multiple stages, the possibility of forming fine conductive parts that may communicate with the base material can be significantly reduced.

[0056] Furthermore, even in the above-mentioned wet plating, if the base material is immersed in the plating solution for a long time, the iron-plated portion formed around the conductive portion can cover the entire phosphate layer, and as a result, as in the case of dry plating, an iron-plated portion can be formed over the entire base material so as to cover almost the entire phosphate layer including the conductive portion 22.

[0057] In this way, when the phosphate chloride layer formed over the entire base material is laminated, the laminated phosphate chloride layer becomes thick, and conductive parts caused by thin thickness can be eliminated, and conductive parts caused by pinholes can also be eliminated, so that an insulating layer having high insulation properties, not only high electrical resistance but also high voltage resistance, can be formed. In addition, peeling and cracking of the insulating layer caused by the difference in thermal expansion coefficient between the base material and the insulating layer can be prevented, and deterioration under high temperature, high humidity, and other environments can be suppressed.

[0058] The insulating layer is formed by completing the third step described above, but it is also possible to form a conductive layer, a conductive pattern, electronic elements, etc., by subsequent processing. For example, a conductive layer 60 having electrical conductivity may be disposed on an insulating layer 50 (an insulating layer including a phosphate layer 20 and a second phosphate layer 40) shown in Fig. 10. Such a conductive layer 60 can be formed directly on the insulating layer 50 by, for example, lamination printing using a conductive paste, pad printing, painting, plating, inkjet printing, sputtering, spray coating, hot-dip plating, thermal spraying, etc.

[0059] The conductive layer 60 may be formed in various shapes, such as a planar shape, a linear shape, a mesh shape, a geometric pattern, a dot shape, or a combination of these shapes. Therefore, the conductive layer may be formed in a linear shape to form a conductive pattern. Alternatively, the conductive layer may be formed in a planar shape and then patterned to form a conductive pattern. In this case, the patterning may be, for example, etching, cutting, laser processing, masking, or the like, as long as it removes unnecessary portions.

[0060] In addition, an electric element may be formed at the same time as the conductive layer is formed. For example, a coil may be formed by forming the conductive layer in a linear shape and spiraling it along the outer peripheral surface of the base material, or a resistive portion with high electrical resistance may be formed by narrowing the line width or reducing the line thickness of the linear conductive layer. In addition, since an insulating layer exists between the base material and the conductive layer, a capacitor can be formed. Needless to say, a capacitor may be formed by alternately forming insulating layers and conductive layers on the conductive layer.

[0061] In addition, a protective layer may be formed on the conductive layer. For example, the material for the protective layer may be an ionizing radiation curable resin that is cured by light or an electron beam, a thermosetting resin that is cured by generating heat, or a photosensitive resin that is cured by ultraviolet light. Alternatively, a resin layer serving as the protective layer may be formed by a technique such as painting, dipping, or spraying.

[0062] The target components on which the insulating layer is formed include buildings such as residential houses, apartment buildings, and buildings; buildings and structures such as bridges, steel towers, railways, pipelines, plants, power plants, wind power generation equipment, and solar power generation equipment (hereinafter, buildings and structures will be collectively referred to as structures); various components such as building materials and structural materials used therein; industrial machinery such as construction machinery and machine tools, other mechanical devices, and consumables such as fastening members, gears, blades, and holding members that constitute them; or component parts such as springs, bearings, and linear guides; various means of transportation such as rockets, aircraft, submarines, ships, trains, buses, trucks, passenger cars, motorcycles, bicycles, and elevators; and components used in a variety of situations, such as office and household equipment and daily necessities.

[0063] In addition, the insulating layer in each of the above-mentioned embodiments may be provided on the entire surface of the member, or may be provided on a part of the surface of the member. For example, when the above-mentioned patterning is performed, the insulating layer may be formed on the portion where the patterning is performed and its surroundings, and the range in which the insulating layer is formed is appropriately set.

[0064] [Example] The present invention will now be described in more detail with reference to examples, although the present invention is not limited to these examples.

[0065] In the examples and comparative examples, the treatment procedures of the first to third steps, the measurement of insulation properties, the measurement of voltage resistance, and the evaluation of rust prevention properties were carried out as follows.

[0066] [Base material] An SPCC plate having a thickness of 0.475 mm, a width of 30 mm, and a length of 100 mm was used as a base material for forming the insulating layer.

[0067] [First step] A manganese phosphate layer, a zinc manganese phosphate layer, or a zinc phosphate layer was formed on an SPCC plate as a phosphate chloride layer. When forming the manganese phosphate layer, the SPCC plate was immersed in a manganese phosphate treatment solution at 95°C for 11 minutes. The manganese phosphate treatment solution used was one containing phosphoric acid, a manganese compound, and a nickel compound (manufactured by Chemicoat Co., Ltd., product name: Chemicoat No. 618 build-up agent). After immersion in the manganese phosphate treatment solution, the SPCC plate was washed with water.

[0068] [Second process] First, the SPCC plate was immersed in an electroless iron plating solution at 90° C. for 4 minutes. The electroless iron plating solution contained 158.66 g / L of ferrous sulfate (heptahydrate), 120 g / L of sodium hypophosphite, 60 g / L of sodium citrate, and 60 g / L of sodium acetate.

[0069] [Third step] In the third step, the SPCC plate was subjected to the same treatment as in the first step, immersion in the manganese phosphate treatment solution at 95° C. for 11 minutes. After immersion in the manganese phosphate treatment solution, the SPCC plate was washed with water.

[0070] [Insulation measurement] [Needle contact] To confirm the insulation of the surface of the SPCC plate, the resistance was measured. Specifically, the resistance of the manganese phosphate layer was measured using a digital multi-tester (TDB-401) (simply called a tester) made by Ohm Electric Co., Ltd. The probe (contactor) positions were also interchanged when measuring the resistance. That is, the anode probe was placed on the manganese phosphate layer, and the cathode probe was placed on the conductive part of the good conductor of the SPCC plate as the line terminal, and the resistance was measured in both cases.

[0071] [Surface contact] In addition, measurements were performed using planar contact, which is different from needle contact. Planar contact here means that a metal surface (planar contactor) is brought into contact with the manganese phosphate layer. Measurements using planar contact are performed by indirectly contacting the manganese phosphate layer with the anode probe of the tester so that it can be electrically connected via the metal surface.

[0072] Therefore, the anode side probe was attached to the measuring block 74 (see FIG. 11) by inserting it into the measuring block 74 which served as a planar contactor. The tip of the negative side probe was in contact with a conductive part of the SPCC plate with good conductivity other than the manganese phosphate layer. Note that the planar contactor here is in the shape of a block, and is a measuring block 74 separate from the probe, but it goes without saying that it does not necessarily have to be separate, and the probe itself may be a planar contactor.

[0073] As shown in Fig. 11(a), the measurement block 74 has a bottom 76 forming a metal surface. The bottom 76 is in planar contact with the manganese phosphate layer, and the probe 72 is inserted into a hole 78 in the measurement block 74 and the tip is brought into contact with the bottom 76, whereby the probe 72 indirectly contacts the manganese phosphate layer via the bottom 76. Note that the measurement block 74 does not necessarily need to have a hole 78, and it is sufficient if the measurement block 74 is provided integrally with the probe 72 so that the probe 72 is in planar contact. Here, the bottom 76 of the measurement block 74 is circular with a diameter of 10 mm and an area of ​​approximately 78 mm 2 The following was used.

[0074] Generally, the resistance is measured by needle contact, but when the inventors used a commercially available measurement probe to check, they found that different resistance values ​​were measured depending on the contact point of the probe. That is, when the probe contacted the conductive part of the manganese phosphate layer, the resistance was measured as low, but when the probe contacted a part that avoided the conductive part, the resistance was measured as high. Therefore, in this embodiment, in order to confirm whether or not the layer was insulated more objectively than with the general method, the measurement was performed by surface contact.

[0075] Although the other probe was brought into direct contact with the SPCC plate, it goes without saying that it may be electrically connected to the SPCC plate via the measurement block 74. Also, the bottom 76 of the measurement block 74 has been described as being in surface contact with the manganese phosphate layer, but this is not limiting.

[0076] For example, bottom 76 may be capable of covering the manganese phosphate layer over a predetermined area or more and of making point contact with many points of the manganese phosphate layer. That is, bottom 76 may have a plurality of protruding portions on the surface facing the manganese phosphate layer that can make contact with the manganese phosphate layer. Needless to say, bottom 76 may have a shape having both a portion that makes planar contact with the manganese phosphate layer and protruding portions that make point contact with the manganese phosphate layer.

[0077] [Water + surface contact] Since the surface of a typical manganese phosphate layer is non-uniform in thickness and has many fine conductive parts, in addition to measuring the resistance value described above, conductive water was applied between the measurement block 74 and the manganese phosphate layer as a conductive fluid, and the conductive parts were filled with the fluid, and the resistance value was measured.

[0078] [Voltage resistance test] Using a digital insulation resistance meter (MY600 manufactured by Yokogawa Measurement Corporation) as a voltage withstand meter, the electrodes were placed against the SPCC plate and a voltage was applied. The resistance value was measured while gradually increasing the applied voltage in the order of 5 [V], 50 [V], 125 [V], 250 [V], 500 [V], and 1000 [V].

[0079] The effective maximum displayed resistance value of a voltmeter is 100 [MΩ] when an applied voltage is 50 [V], 250 [MΩ] when an applied voltage is 125 [V], 500 [MΩ] when an applied voltage is 250 [V], 2000 [MΩ] when an applied voltage is 500 [V], and 4000 [MΩ] when an applied voltage is 1000 [V].

[0080] The applied voltage when the resistance value was measured below a certain value was taken as the dielectric breakdown voltage (upper limit of withstand voltage). In the withstand voltage test, both the needle contact and surface contact measurement methods were applied. Furthermore, measurements were also performed with the anode probe and cathode probe interchanged in position.

[0081] [Evaluation of rust prevention] To confirm the rust prevention properties, a saltwater immersion experiment was conducted in which the SPCC plate was immersed in a 5 wt% NaCl solution. In the saltwater immersion experiment, the immersion time from immersion in saltwater until rust appeared on the SPCC plate was measured.

[0082] [Comparative Examples 1 and 2, Examples 1 to 9] By the treatments in the first to third steps described above, SPCC plates having manganese phosphate layers with the number of layers shown in Tables 1 and 2 were obtained. The SPCC plate of Comparative Example 1 had zero manganese phosphate layers that had not been treated in the first to third steps. The SPCC plate of Comparative Example 2 had one manganese phosphate layer that had only been treated in the first step.

[0083] The SPCC plates of Examples 1 to 9 were treated in the first to third steps to form any one of 2 to 10 manganese phosphate layers. [Table 1] [Table 2]

[0084] The conductive points (+) in Tables 1 and 2 indicate the measurement results when the anode probe was in contact with a conductive point (such as the surface of the base material of the SPCC plate) and the cathode probe was in contact with the manganese phosphate layer. The conductive points (-) indicate the measurement results when the anode probe was in contact with the manganese phosphate layer and the cathode probe was in contact with a conductive point.

[0085] The results obtained in each comparative example and each example are shown in Tables 1 and 2. The thickness of the SPCC plates in Comparative Example 2 and Examples 1 to 9 was almost constant regardless of the number of manganese phosphate layers. The reason why the tester measurement result in Table 1 is OL is because it exceeded the resistance value of 40 [MΩ] that can be measured by the tester. Furthermore, the resistance value in Table 2 that is marked as dielectric breakdown indicates that dielectric breakdown occurred when the corresponding voltage was applied. Therefore, the dielectric breakdown voltage does not necessarily correspond to the applied voltage.

[0086] Specifically, in the results shown for the conductive point (+) of needle contact in Example 1 in Table 2, dielectric breakdown occurred at an applied voltage of 500 [V]. This is because when the applied voltage was set to 250 [V], the resistance value exceeded 50 [MΩ] and became unmeasurable, so the next time the applied voltage was set to 500 [V], dielectric breakdown occurred. In such cases, the resistance value was recorded as dielectric breakdown and the applied voltage was recorded as 500 [V]. Therefore, the actual dielectric breakdown voltage is considered to be an applied voltage in the range of more than 250 [V] and less than 500 [V].

[0087] It can be seen that Examples 1 to 9 had higher resistance values ​​measured by a tester and significantly improved insulation properties compared to Comparative Examples 1 and 2. This is believed to be because an iron-plated portion was formed in the conductive portion of the manganese phosphate layer formed in the first process, and a manganese phosphate layer was further formed on the iron-plated portion, blocking the previously conductive portion.

[0088] In addition, in the needle contact of Comparative Example 2, the resistance value was measured as not measurable (OL: 40 MΩ or more), but in the planar contact, the value was in the range of several KΩ to several MΩ. This is because the manganese phosphate layer (phosphate chloride layer) itself has countless conductive parts, which obviously affect the conductivity (insulation) and voltage resistance. Therefore, the planar contact measurement can detect the conductivity that could not be detected in the measurement of the electrical resistance value using a needle probe because the contact area with the object to be measured is too small and the total number of fine conductive parts is small. That is, in the planar contact measurement, the contact surface of the measurement block 74 has an area significantly larger than the tip of the needle probe, and the total number of fine conductive parts present within the range of this contact surface increases significantly, so that conductivity is expressed through the measurement block 74. As a result, this area effect allows the electrical resistance value of layers such as insulating layers to be measured more accurately, and the presence or absence of fine conductive parts can be accurately determined to accurately confirm the level of insulation.

[0089] Moreover, in Examples 1 to 9, the withstand voltage is improved compared to Comparative Example 2. Furthermore, the increase in the number of layers tends to further improve the withstand voltage. This is believed to be because the withstand voltage is improved by blocking the conductive parts of the manganese phosphate layer. Furthermore, it is believed that the more times the second and third steps are performed, i.e., the more the number of manganese phosphate layers increases, the more the conductive parts of the manganese phosphate layer are blocked, resulting in a decrease in the total number of conductive parts, which can improve the withstand voltage.

[0090] Furthermore, in the evaluation of rust prevention, when the manganese phosphate layer had 10 layers, no rust was observed even after 240 hours, which suggests that there were almost no fine conductive parts on the surface of the manganese phosphate layer. This also suggests that the more times the second and third steps were repeated, i.e., the more the number of manganese phosphate layers increased, the less conductive parts there were in the manganese phosphate layer.

[0091] In addition, in each of the embodiments, the insulating layer formed on the SPCC plate has a withstand voltage performance of at least 250 [V] or more. When the conductive layer 60 described above is used as an electric element and the power source connected to the conductive layer 60 is a lithium ion secondary battery, the voltage of the lithium ion secondary battery is 3.7 [V], so the insulating layer has a withstand voltage performance of several tens of times or more the voltage of the power source voltage. Of course, the insulating layer has a withstand voltage performance equal to or higher than that of primary batteries such as manganese dry batteries, nickel batteries, and lithium batteries, and secondary batteries such as nickel-cadmium batteries and nickel-metal hydride batteries.

[0092] Although not shown in the table, it has been confirmed that even when a zinc phosphate layer or a zinc manganese phosphate layer is formed as the insulating layer instead of a manganese phosphate layer, the withstand voltage tends to improve as the number of layers (which may be considered as the number of times the second and third steps are repeated) increases.

[0093] In addition, it is clear that the resistance value differs greatly depending on the positions of the anode probe and the cathode probe in each example. Specifically, the resistance value is significantly higher when the anode probe is in contact with the manganese phosphate layer (when the cathode probe is in contact with the conductive part with good conductivity) than when the anode probe is in contact with the manganese phosphate layer (when the cathode probe is in contact with the conductive part with good conductivity) compared with the case where the anode probe is in contact with the manganese phosphate layer. From this, it is considered that the member with insulating layer of the present invention, in which a phosphate layer is formed on the base material as in the present invention, has a rectifying effect that makes it easier for the current to flow from the base material side, which is a metal, to the phosphate layer, which is an insulating layer.

[0094] Therefore, by utilizing the rectifying effect, a member in which the phosphate layer 20 is formed on the base material 10 can be used as a rectifying element. That is, a rectifying element is formed by joining the base material 10 as a metal with the phosphate layer 20, and a terminal is provided directly or indirectly on the base material 10, and a terminal is provided directly or indirectly on the phosphate layer 20. The direction of the voltage applied to the rectifying element is not particularly limited, and the terminal provided on the base material 10 may be either the anode or the cathode.

[0095] The conductive fluid used in the above-mentioned insulation measurement is not limited to conductive water, and may be, for example, salt water, silver paste, ionic liquid, etc., but it is preferable to select a conductive fluid that does not cause reactions such as oxidation or dissolution with the base material (SPCC plate).

[0096] The size of the measuring block 74 used for the planar contact is not particularly limited, but the bottom 76 may be made smaller so that the area of ​​the surface of the bottom 76 facing the manganese phosphate layer is smaller than the area of ​​the bottom 76 in FIG. 11(a) as shown in FIG. 11(b). In particular, by making the bottom 76 smaller, the work of filling the gap between the measuring block 74 and the manganese phosphate layer with a conductive fluid can be easily performed. It is preferable to insulate the side surface of the planar contactor, i.e., the measuring block 74, so that the conductive fluid interposed between the measuring block 74 and the surface of the manganese phosphate layer, which is the measurement target portion, does not become conductive even if it overflows between the measuring block 74 and the manganese phosphate layer and contacts the side surface of the measuring block 74.

[0097] The present invention includes the following features.

[0098] The method for forming an insulating layer of the present invention includes a first step of subjecting a base material to a high-resistance layer forming treatment having high electrical resistivity by surface treatment, a second step of subjecting the base material that has undergone the first step to a metal plating portion forming treatment capable of forming a high-resistance layer, and a third step of subjecting the base material that has undergone the second step to a high-resistance layer forming treatment.

[0099] In the insulating layer forming method of the present invention, the second step forms a metal plating on the fine conductive parts of the high resistance layer formed in the first step.

[0100] In addition, in the method for forming an insulating layer of the present invention, the high-resistance layer is a phosphate layer formed by phosphating, and the metal-plated portion is mainly composed of a metal that can be phosphating treated and / or oxidized.

[0101] In the insulating layer forming method of the present invention, the high-resistance layer in the third step is formed by a phosphating chemical treatment and / or an oxidation treatment.

[0102] In addition, the insulating layer formation method of the present invention is a method for forming an insulating layer having a high level of electrical insulation on a base material on which a high-resistance layer cannot be directly formed, and includes a preliminary step of forming a metal plating portion in a layered manner on the base material, a first step of forming a high-resistance layer having high electrical resistivity in the metal plating portion by surface treatment, a second step of forming a metal plating portion capable of forming a high-resistance layer on the base material that has undergone the first step, and a third step of forming a high-resistance layer on the metal plating portion formed in the second step by applying a treatment to form a high-resistance layer on the base material that has undergone the second step.

[0103] In addition, in the method for forming an insulating layer of the present invention, the high-resistance layer is a phosphate layer formed by phosphating, and the metal-plated portion is mainly composed of a metal that can be subjected to phosphating and / or oxidation treatment.

[0104] In the insulating layer forming method of the present invention, the high-resistance layer in the third step is formed by a phosphating chemical treatment and / or an oxidation treatment.

[0105] In the method for forming an insulating layer of the present invention, the second step and the third step are alternately repeated.

[0106] In the second step of the insulating layer forming method of the present invention, a metal plating portion is formed by wet plating.

[0107] In the method for forming an insulating layer of the present invention, the metal plating portion contains iron, tin, zinc or nickel as a main component.

[0108] The method for forming an insulating layer of the present invention also includes a step of forming a conductive layer on the outermost high-resistance layer.

[0109] Furthermore, in the method for forming an insulating layer of the present invention, the conductive layer has a planar, linear, mesh, geometrical pattern and / or dotted shape, or a combination thereof.

[0110] In the method for forming an insulating layer of the present invention, the conductive layer forms a conductive pattern.

[0111] In the method for forming an insulating layer of the present invention, the width, thickness and direction of the conductive layer provided on the high resistance layer are set so as to form an electronic element.

[0112] In addition, the member with an insulating layer of the present invention has a phosphate layer formed on the surface of the base material, and a conductive liquid is applied to the surface of the phosphate layer. The anode side probe is brought into contact with the conductive portion and the cathode side probe is brought into contact with the phosphate layer. 2 The resistance value when measured with a surface probe is 190KΩ or more.

[0113] Furthermore, the member with insulation layer of the present invention has an insulation layer composed of a substantially uniform phosphate layer on the surface of the base material.

[0114] Furthermore, the member with an insulating layer of the present invention is a surface insulating layer in which the insulating layer is insulated throughout the entire surface formed by the insulating layer.

[0115] The member with an insulation layer of the present invention has an insulation layer mainly composed of a phosphate layer on the surface of the base material, and metal oxides are scattered in the insulation layer.

[0116] The member with an insulating layer of the present invention has a conductive layer on the insulating layer.

[0117] Furthermore, in the member with an insulating layer of the present invention, the conductive layer has a planar, linear, mesh, geometrical pattern and / or dotted configuration, or a combination thereof.

[0118] In the member with an insulating layer of the present invention, the conductive layer forms a conductive pattern.

[0119] In the member with an insulating layer of the present invention, the width, thickness and direction in which the conductive layer is provided on the high-resistance layer are set so as to form an electronic element.

[0120] Furthermore, in the member with an insulating layer of the present invention, the insulating layer has a withstand voltage performance that exceeds the voltage applied to the conductive layer.

[0121] In addition, the resistance measurement method of the present invention is a resistance measurement method for measuring the resistance value of a high-resistance layer formed on a component, and measures the resistance of the high-resistance layer using a measurement device that covers the high-resistance layer over an area of ​​a predetermined size or more and has a first contactor that makes point contact and / or planar contact with multiple locations on the high-resistance layer, and a second contactor that makes contact with the surface of the component other than the locations where the first contactor makes contact.

[0122] In the resistance measuring method of the present invention, the member has good electrical conductivity, and the second contactor comes into contact with a portion of the member having good electrical conductivity.

[0123] In the resistance measuring method of the present invention, the member is covered with a high resistance layer, and the second contactor is brought into contact with the surface covered with the high resistance layer.

[0124] In addition, in the resistance measurement method of the present invention, the first contactor is a member that is separate from the measuring device and makes point contact with multiple locations on the high resistance layer and / or makes planar contact with the high resistance layer, and the contactor of the measuring device indirectly contacts the high resistance layer via the first contactor.

[0125] In addition, in the resistance measuring method of the present invention, a conductive fluid is placed between the high resistance layer and the first contact.

[0126] In addition, the junction rectifying element of the present invention is a junction rectifying element formed by bonding a metal and a phosphate, and has an anode terminal provided directly or indirectly on the metal, and a cathode terminal provided directly or indirectly on the phosphate.

[0127] In addition, the junction rectifying element of the present invention is a junction rectifying element formed by bonding a metal and a phosphate, and has a cathode terminal provided directly or indirectly on the metal, and an anode terminal provided directly or indirectly on the phosphate.

[0128] Furthermore, in the junction rectifying element of the present invention, the metal is mainly composed of iron, which can be subjected to a phosphate chemical treatment.

[0129] In the junction rectifying element of the present invention, the phosphate is a phosphate chloride layer. [Explanation of symbols]

[0130] 10...base material, 15...metal plated portion, 20, 45...phosphate layer, 22...conductive portion, 30...iron plated portion, 40...second phosphate layer, 42...metal oxide, 50...insulating layer, 60...conductive layer.

Claims

1. 1. An electrical resistance layer comprising a second phosphate layer formed by phosphate treating a metal plating portion applied to a conductive portion present in a first phosphate layer provided on the surface of a base material.

2. 2. The electrical resistance layer according to claim 1, characterized in that the conductive portion remaining in the second phosphate layer is subjected to metal plating and the phosphate treatment in at least one stage, thereby giving the layer an appropriate resistance value.

3. 2. The electrically resistive layer of claim 1, wherein the first phosphate layer comprises one of a manganese phosphate layer, a zinc manganese phosphate layer, or a zinc phosphate layer.

4. 2. The electrical resistance layer according to claim 1, wherein the first phosphate layer and the second phosphate layer constitute an insulating layer that insulates the entire surface of the base material.

5. 5. The electrical resistance layer of claim 4, further comprising a conductive layer formed on the insulating layer.

6. 6. The electrical resistance layer according to claim 5, wherein the insulating layer has a withstand voltage performance exceeding a predetermined voltage applied to the conductive layer.

7. The electrically resistive layer of claim 6 , wherein the conductive layer comprises a conductive pattern.

8. 1. An electrical resistance layer comprising a metal oxide formed by oxidizing a metal plating applied to a conductive portion present in a phosphate layer provided on the surface of a base material.

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