Method for continuously producing sheet having structure in which entire surface of fabric or nonwoven fabric is covered with coating formed by collection of powder of any one material of metal, alloy, metal oxide, and nitride, the powder having micron-sized particle diameter and being joined by friction welding

Abstract

To continuously produce a sheet, ensure that the produced sheet is nonflammable and has mechanical strength as a sheet, enable the sheet to be cut, and allow the cut sheet to be pressure-bonded to a base material or a component.SOLUTION: A plurality of cylindrical rollers, each having a length equal to the container width and having the same diameter, is arranged in parallel to the container width with spacing from each other. A collection of powder of any one of a metal, an alloy, a metal oxide, and a nitride, and an alcohol having viscosity of 3-11 mPa s at 20°C are filled into the container. All rollers except for the first and last rollers are immersed in the suspension. Thereafter, a fabric or a nonwoven fabric drawn from a textile material is sequentially brought into contact with the plurality of cylindrical rollers and further compressed by being sandwiched in a gap between two work rolls of a multi-stage rolling machine. This enables continuous production of a sheet having a structure in which the entire surface of the fabric or nonwoven fabric is covered with a coating formed by a collection of powder joined by friction welding.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a manufacturing method for continuously manufacturing a sheet in which the entire fabric or non-woven fabric is covered with a film formed by a collection of one type of powder made of any of metals, alloys, metal oxides, or nitrides having a micron size and joined by friction welding, by continuously performing all processes consisting of the following three processes. In the first step, a plurality of columnar rollers that rotate at the same peripheral speed with a rotation time per rotation longer than 20 seconds are provided in a container having a width wider than the width of the sheet to be manufactured and a length equal to the length where a plurality of columnar rollers are provided, parallel to each other and spaced apart on the side surface forming the width of the container. After that, a collection of one type of powder made of any of metals, alloys, metal oxides, or nitrides having a micron size and having a weight greater than the weight required for continuously manufacturing the sheet, and an alcohol having a viscosity of 3 - 11 mPa·s at 20°C are used. The smaller the size of the powder, the more inferior the symmetry of the powder shape, and the higher the hardness of the powder, the higher the viscosity of the alcohol is used. An alcohol having a weight such that all the rollers except the first and the last of the plurality of columnar rollers are immersed is filled into the container together with the collection of powder, and the alcohol is stirred to create a suspension. Although there are many fine voids in the fabric and non-woven fabric, since the alcohol constituting the suspension has a viscosity of 3 - 11 mPa·s at 20°C, the suspension fills the voids of the fabric and non-woven fabric, and the suspension adsorbs on the surfaces of the fabric and non-woven fabric. In the second step, a fabric or non-woven fabric wound around a roll having the width of the sheet to be manufactured is set in a drawing-out device, and the fabric or non-woven fabric is continuously drawn out from the roll at a speed corresponding to the peripheral speed of the plurality of cylindrical rollers described above. Thereafter, the drawn-out fabric or non-woven fabric comes into contact with the uppermost part of the first roller, changes the moving direction by 90 degrees and moves downward, is immersed in the suspension, then comes into contact with the second roller rotating in the opposite direction, changes the moving direction by 90 degrees and moves, and moves parallel to the bottom surface of the container from the second roller from the last to the second roller in the state of being immersed in the suspension. After that, it comes into contact with the second roller from the last, changes the moving direction by 90 degrees and moves, is pulled up from the suspension, then comes into contact with the last roller rotating in the opposite direction, changes the moving direction by 90 degrees and moves, and the fabric or non-woven fabric with the suspension evenly attached thereto moves into the gap between the two work rolls of the multi-stage rolling mill. The third step is to prepare a multi-stage rolling mill having two work rolls that, firstly, have the same width wider than the width of the sheet to be manufactured, secondly, have the same diameter smaller than 1 / 10 of the width of the sheet, thirdly, set the thickness of the sheet to be created as the gap, fourthly, rotate in opposite directions at the same peripheral speed as the peripheral speed at which the plurality of cylindrical rollers in the first step rotate, and fifthly, heat up to a temperature 10 °C higher than the boiling point of the alcohol constituting the suspension. Next, insert the tip of the fabric or non-woven fabric that has completed the treatment in the second step into the gap between the two work rolls. As a result, the tip of the fabric or non-woven fabric is drawn into the gap between the two work rolls and receives compressive stress from the two work rolls. At this time, first, the alcohol vaporizes from the suspension evenly attached to the fabric or non-woven fabric, and the powder precipitates overlapping on the fabric or non-woven fabric, and the fabric or non-woven fabric is covered with the accumulation of the powder. Next, the accumulation of the powder comes into contact with the two work rolls, and the surface layer of the accumulation of the powder moves to the thicker side of the two work rolls. After this, compressive stress is evenly applied to the accumulation of the powder and the fabric or non-woven fabric. At this time, the powder moves to fill the voids in the accumulation of the powder, and the fabric or non-woven fabric undergoes compressive deformation. Furthermore, the powder in contact with the fabric or non-woven fabric applies shear stress to the fabric or non-woven fabric, and the portion where the shear stress is applied breaks. On the other hand, since the powder is as small as the micron size and the fabric or non-woven fabric is covered with the accumulation of the powder, an extremely large amount of powder comes into contact with the fabric or non-woven fabric. For this reason, an extremely large number of breakage points are formed in the fabric or non-woven fabric, and thereby the fabric or non-woven fabric is divided. Furthermore, the voids on the front and back surfaces of the broken portion of the fabric or non-woven fabric and the divided fabric, or the voids on the front and back surfaces of the divided non-woven fabric, are filled with the powder moving due to the compressive stress applied to the powder and are completely filled with the powder. Furthermore, compressive stress is evenly applied to the accumulation of the powder, and the powder particles are joined by friction and pressure bonding at all contact portions where adjacent powder particles in the accumulation of the powder come into contact, and the overlapping accumulations of the powder are joined by friction and pressure bonding at all contact portions where the powder particles come into contact with each other.As a result, all the voids in the aggregate of powder joined by friction welding are confined inside the aggregate of powder, and the aggregate of powder is formed as a film without voids communicating with the outside. Further, the film is joined to the divided fabric or the divided nonwoven fabric by friction welding. Such a phenomenon continuously occurs in the aggregate of powder sandwiched between the gaps of the two work rolls and the fabric or nonwoven fabric, and a sheet having a configuration in which the film is joined by friction welding to the entire divided fabric or divided nonwoven fabric is discharged from the gaps of the two work rolls as a sheet having the thickness of the gaps of the two work rolls. The discharged sheet is wound up by a winding device that rotates at the same speed as the rotational speeds of the two work rolls. As a result, since the moving speed related to the fabric or nonwoven fabric from the movement of the fabric or nonwoven fabric drawn from the workpiece to the winding of the sheet by the winding machine is the same, the sheet is continuously manufactured. That is, the fabric or non-woven fabric is a lightweight, thin, inexpensive industrial product with few size restrictions and can be easily cut, so there are no shape restrictions. However, when using the fabric or non-woven fabric as a sheet, its mechanical strength is too small. Also, both the fabric and the non-woven fabric are flammable. On the other hand, in the present invention, the fabric or non-woven fabric is used as a means for adsorbing a suspension in which a collection of powder is dispersed in alcohol. Further, when the alcohol is vaporized, the entire fabric or non-woven fabric is covered with a collection of powder. Furthermore, the collection of powder and the fabric or non-woven fabric are compressed to form a sheet in which a film composed of a collection of powder joined by friction pressure bonding is joined to the entire fabric or non-woven fabric. As a result, the sheet has mechanical strength based on the bonding force between the powders, and the properties of the powder are imparted to the sheet. Also, the collection of powder joined by friction pressure bonding is a film formed by overlapping micron-sized collections of powder and joined, and its thickness is less than 0.25 mm. Therefore, even a film formed by joining powders with high hardness can be cut by the sheet. Accordingly, there are no restrictions on the size and shape of the sheet to be cut. Note that the thickness of the sheet to be manufactured is the gap between two work rolls, so the thickness of the sheet to be manufactured in advance can be set. Furthermore, the surface of the sheet has irregularities based on the size of the powder and the irregularities on the surface of the powder. Therefore, when the cut sheet is overlapped on the surface of a substrate or component made of various materials and the entire cut sheet is evenly compressed, the cut sheet is pressure-bonded to the surface of the substrate or component through the above-mentioned irregularities. As a result, the properties of the powder can be imparted to the substrate or component. Also, the film formed by the collection of powder joined by friction pressure bonding has no voids communicating with the outside, so it has airtightness that blocks gas with respect to the fabric or non-woven fabric. Therefore, the fabric or non-woven fabric does not self-ignite or catch fire. Furthermore, even when the sheet is heated to the thermal decomposition temperature of the fabric or non-woven fabric, the combustible substances generated when the fabric or non-woven fabric is thermally decomposed are not discharged to the outside. Therefore, the sheet is non-combustible. Also, the film has heat resistance corresponding to the heat-resistant temperature of the powder. Furthermore, the surface of the film has water repellency that repels all liquids. Therefore, the sheet has corrosion resistance corresponding to the corrosion resistance of the powder. As described above, the manufactured sheet is thinner, lighter in weight, and has mechanical strength, incombustibility, heat resistance, and corrosion resistance than conventional synthetic resin sheets or conventional metal sheets. Note that among metal sheets, the aluminum sheet has the thinnest thickness, and according to JIS H4000, the plate thickness is 0.2 mm or more. Furthermore, powders made of materials such as metals, alloys, metal oxides, or nitrides are composed of extremely many types of materials. On the other hand, the sheet has the inherent properties of the powders used. Therefore, the sheet has extremely many types of properties based on the inherent properties of the powders. As a result, the sheet is used for extremely many applications. Furthermore, by pressing the cut sheet onto substrates or parts made of various materials, sizes, and shapes, various properties of the powders are imparted to the substrates or parts. By the way, there are two types of fabrics: woven and knitted. Woven fabric is made by weaving warp threads and weft threads made of natural fibers or chemical fibers into a fabric, and there are three types of weaving methods: plain weave, twill weave, and damask weave. In contrast, knitted fabric is a fabric knitted in a loop shape. On the one hand, woven fabric has no stretchability, while knitted fabric has stretchability, but woven fabric is cheaper than knitted fabric. Also, both woven fabric and knitted fabric are easily deformed but have low mechanical strength. Also, both woven fabric and knitted fabric have extremely many concave parts and voids on the surface, and the powders are crimped to the extremely many irregularities, and the powders fill the extremely many voids. When using the fabric as a frame for supporting the collection of powders, since stretchability is not required, a cheaper woven fabric made of plain weave or twill weave is suitable for the frame for supporting the collection of powders. On the other hand, non-woven fabric is a non-woven cloth-like material. Fibers are accumulated in a certain direction or randomly and chemically bonded with an adhesive resin, or mechanically entangled, or entangled with a water flow under pressure, or bonded with heat-fused fibers to make it. Therefore, it is porous and has numerous voids, and has air permeability, filtration property, and moisture retention property. Accordingly, the numerous voids can be filled with powder. Also, since non-woven fabric can form fibers into a sheet as they are, there is no need to spin fibers like woven or knitted fabrics. For this reason, it can be manufactured at a lower cost than woven or knitted fabrics. Therefore, non-woven fabric is suitable for a frame body that supports a collection of powder, similar to a fabric made of plain weave or twill weave. Note that natural fibers, chemical fibers, and glass fibers are used as raw materials for non-woven fabric.

[0002] The inventor has previously filed a patent as Patent No. 6734691 for forming a molded body of a synthetic resin having non-combustibility and imparted conductivity by covering a molding material with an aggregate of metal nanoparticles bonded with metal and molding a molded body using the molding material. Also, an aggregate of metal nanoparticles generated by thermal decomposition of a metal compound is dispersed in an organic compound, and a plurality of fibers or yarns, or a plurality of fabrics or non-woven fabrics having a predetermined size are put into this suspension, and a container containing the suspension is placed in a chamber of a vacuum impregnation device. After that, the pressure inside the chamber is reduced to a pressure lower than the vapor pressure of the organic compound, and both the voids inside and the concave portions of the surface irregularities of the fibers, yarns, fabrics, or non-woven fabrics are filled with aggregates of metal fine particles, and the surface of the fibers, yarns, fabrics, or non-woven fabrics is covered with aggregates of metal fine particles, and a method for manufacturing fibers, yarns, fabrics, or non-woven fabrics imparted with metal properties has been filed as Japanese Patent Application No. 2021-205624. On the other hand, the present invention is different from the prior application in that a sheet joined with a film composed of an aggregate of one kind of powder made of any material of metal, alloy, metal oxide, or nitride having a size in the micron size joined by friction pressure bonding is continuously manufactured on a fabric or non-woven fabric having a width equal to the width of the sheet to be manufactured.

Background Art

[0003] Many sheets composed of aggregates of metal or alloy powders are used as conductive sheets. Also, many sheets composed of aggregates of metal oxide or nitride powders are used as insulating sheets. First, the uses of conductive sheets and the prior patent documents related to these uses will be described. In recent years, sheets made of conductive fibers have been studied as electromagnetic shielding materials for shielding electromagnetic waves generated from electronic devices such as mobile phones, or fabrics made of conductive fibers have been studied as antistatic materials or static eliminators for suppressing the generation of static electricity. Also, among conductive fibers, the technological development of imparting conductivity to polymer materials is being carried out most actively. This technology for imparting conductivity is divided into two categories: a technology for dispersing conductive substances and a technology for forming metal films. For example, a technology using a polymer composition mixed with a conductive substance such as carbon powder or metal powder (see, for example, Patent Document 1), a technology for forming a metal vapor deposition film such as tin oxide on a plastic molded article by a vacuum vapor deposition method or the like (see, for example, Patent Document 2), a technology for forming a metal film on the surface of a polymer fiber material by electroless plating (see, for example, Patent Document 3), and the like can be mentioned.

[0004] However, in a polymer composition filled with a conductive substance such as carbon powder or metal powder, since it is composed of a polymer in which conductive particles are dispersed and a non-conductive polymer, there is a problem that the conductive part and the non-conductive part are likely to peel off. Also, in order to obtain conductivity close to that of metal, a path in which conductive particles are continuously joined must be formed in the sheet. For this reason, the filling rate of conductive particles must be increased, and there is also a problem that the higher the filling rate of conductive particles, the more the characteristics of the polymer composition are lost. That is, in the technology of dispersing conductive particles in a fabric or non-woven fabric, unless a structure in which current continuously flows through the conductive particles is formed in the fabric or non-woven fabric, conductivity close to that of a metal cannot be obtained in the fabric or non-woven fabric. On the other hand, when trying to increase the conductivity by increasing the filling rate of the conductive particles to 10% or more, the dispersibility of the conductive particles begins to deteriorate, and a high filling rate of the conductive particles cannot be obtained. Thus, in the technology of filling a fabric or non-woven fabric with conductive particles, it is difficult to fill the fabric or non-woven fabric with a high filling rate of conductive particles, so it is fundamentally difficult to make the properties of the fabric or non-woven fabric approach those of a metal.

[0005] On the other hand, in the technology of forming a metal film by a vacuum deposition method or the like, there are problems such as the abrasion resistance, weather resistance of the metal film, and deterioration of physical properties due to chemical changes during long-term use. In addition, forming a metal film requires high manufacturing costs and has limitations in actual use. Furthermore, in the technology of forming a metal film by electroless plating, since many processes and high-level technologies are required, the manufacturing cost becomes high. Also, when using or processing the conductive sheet, friction and bending are applied to the fabric or non-woven fabric, and there is a problem that the metal film peels off from the fabric or non-woven fabric. That is, the technology of forming a metal film on the surface of a fabric or non-woven fabric by a vacuum deposition method or the like is a method of forming a metal film by depositing the deposited metal foils. Therefore, since the deposited metal foils are not bonded to each other by a metal bond or a covalent bond, the bonding force between the metal foils is extremely weak, and when stress is applied to the metal film, the metal foils are easily peeled off. Thus, the problem that the metal film is easily peeled off is due to the lamination of the deposited metal foils, so this problem cannot be fundamentally solved.

[0006] Next, in the case of the insulating sheet, since the case of forming an insulating layer on a conductor is the most general, the prior patent documents related thereto will be described. There are various methods for forming an insulating layer on a conductor. For example, Patent Document 4 describes a method for forming an alumina insulating film by the sol-gel method. That is, an alumina precursor solution with a peptizing agent added is formed into an alumina insulating film on a substrate by electrophoretic deposition on a sol containing an aluminum compound. Specifically, first, an organic solvent such as ethanol is added to the aluminum compound, and further, hydrochloric acid or the like is added as a peptizing agent and stirred to prepare a sol. Next, the sol is placed in a thermostat and stirred for 1 to 3 hours in a temperature range of 40 - 60 °C where gelation does not occur to prepare an alumina precursor solution. Thirdly, in order to bring the hydrolysis and condensation reactions occurring in the alumina precursor solution to an equilibrium state, the alumina precursor solution is held in a thermostat in a temperature range of 40 - 60 °C for 12 hours or more. Fourthly, as the material to be electrodeposited, for example, an electrode with a platinum film formed on the surface of a silicon substrate is prepared, and as the counter electrode, for example, an electrode with a platinum film formed on the surface of a silicon substrate is prepared. The silicon substrate with the two electrodes formed is immersed in the alumina precursor solution, and further, a DC voltage is applied between the electrodes of both substrates until the amount of charge transfer reaches a set value, and the positively charged alumina precursor is deposited on the electrode of the silicon substrate used as the cathode. Fifthly, the silicon substrate on which the alumina precursor has been deposited is placed on a plate and heated and dried under the conditions of 100 °C or higher and 3 minutes or more in an air atmosphere. Sixthly, the alumina precursor deposited on the platinum electrode of the dried silicon substrate is heated from room temperature to 700 °C at a heating rate of 1 - 20 °C / second in an atmosphere where the gas is oxygen, held for 1 minute or more, and the alumina precursor is crystallized to form an insulating film. In this way, an alumina insulating layer is formed on the surface of the platinum electrode. Thus, the processing steps for forming the insulating layer are complex and diverse, and furthermore, since a heat treatment at 700 °C is required, this method for forming the insulating layer is not a general method for forming an insulating layer.

[0007] Patent Document 5 describes the formation of both insulating layers, namely an insulating film on a flat film that covers the display electrodes on the front panel to maintain plasma discharge and an insulating film that covers the address electrodes formed on the rear panel. That is, an insulating paste composed of a thermal polymerization initiator, a thermosetting component, and glass particles is applied to a substrate, the coating film is heated to perform a semi-curing treatment so that the curing rate becomes 30 - 95%, and then further heated to form an insulating layer. Specifically, the coating film is heated to 95°C, left for 30 minutes, and then cooled to 25°C to create a semi-cured film. Further, the semi-cured film is overheated at 380°C for 10 minutes to remove the organic components by heating, and then overheated at 600°C for 10 minutes to sinter the glass particles to form an insulating layer. That is, since electrodes are formed on the substrate, the firing shrinkage rate of the semi-cured film in the convex portion (electrode forming portion) of the substrate is much higher than the firing shrinkage rate of the semi-cured film in the concave portion (non-electrode forming portion) of the substrate, so that an insulating film with high smoothness can be obtained as a whole. For this reason, it is necessary to create a semi-cured film. Since this insulating film has a relatively large area, in order to form an insulating film with excellent smoothness, complicated heat treatment as described above is required. In addition, the chemicals composed of a thermal polymerization initiator and a thermosetting component are special industrial chemicals. Thus, the method for forming the insulating film uses special chemicals, performs complicated and diverse heat treatments, and further requires a heat treatment at 600°C. Therefore, the method for forming this insulating layer is not a general method for forming an insulating layer.

[0008] Patent Document 6 describes a method for forming a low dielectric constant interlayer insulating film required for a highly integrated semiconductor device. Specific substances with good moisture resistance and heat resistance for the low dielectric constant interlayer insulating film include trimethylsilane (TMS) among Si-containing alkyl compounds and tetraethyl orthosilicate (TEOS) among Si-containing alkoxy compounds. However, the electrical conductivity of TEOS is 3×10 -6 S / m, which is only 5×10 6 of that of copper with an electrical conductivity of 59×10 -13 S / m, and the electrical insulation is not sufficient. For this reason, when the electronic circuit operates for a long time, the insulating layer may generate heat due to the leakage current flowing through the insulating layer, and the electronic components arranged on the conductor may be thermally deteriorated.

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Disclosure of the Invention

Problems to be Solved by the Invention

[0010] The problems in continuously manufacturing a sheet in which a film composed of an aggregate of one type of powder made of any of a metal, an alloy, a metal oxide, or a nitride having a size in the micron size range is joined to the entire fabric or non-woven fabric will be described. Note that the size of the powder is such that the majority of the powder has a size smaller than 30 μm, and a very small part of the powder exceeds 100 μm. Therefore, the powder is lightweight. If a fabric or non-woven fabric roll can be used to continuously manufacture a sheet made of a fabric or non-woven fabric, a sheet having a thin thickness, being lightweight, and having a large area can be continuously manufactured. Furthermore, if the sheet can be cut, the constraints on the size and shape of the sheet are eliminated. However, a fabric or non-woven fabric does not have the mechanical strength as a sheet and is flammable. Also, although a fabric or non-woven fabric can be easily cut, the conditions under which the sheet can be cut are unknown. For this reason, there has been no attempt to manufacture a sheet using a fabric or non-woven fabric so far. On the other hand, if a method for manufacturing a sheet in which a film composed of an aggregate of one type of powder made of any of a metal, an alloy, a metal oxide, or a nitride having a micron size is joined to the entire fabric or non-woven fabric can solve the problems described in the following 13 items, not only the properties of the powder made of any of a metal, an alloy, a metal oxide, or a nitride, but also a sheet having mechanical strength, non-combustibility, corrosion resistance, and heat resistance can be continuously manufactured. First, the sheet can be continuously manufactured. As a result, a sheet with a thin thickness, light weight, and a large area can be continuously manufactured at low cost. For this reason, in the process from pulling out the fabric or non-woven fabric from the stock in which the fabric or non-woven fabric is wound to winding up the sheet, it is essential to optimize a plurality of processing methods so that the process is continuous. Second, the sheet can be cut. As a result, there are no restrictions on the size and shape of the sheet. For this reason, it is essential that the thickness of the film composed of the joined powder aggregate is thin enough to be cut. Third, the cut sheet can be pressure-bonded to substrates or parts made of various materials. As a result, various properties of the powder can be imparted to the surface of the substrate or part. Fourth, the sheet has non-combustibility. That is, although any of the powders of a metal, an alloy, a metal oxide, or a nitride is non-combustible, the fabric or non-woven fabric is combustible. If the fabric or non-woven fabric constituting the sheet burns, the function of the sheet is lost and many properties of the sheet are lost. For this reason, it is essential to cover the entire combustible fabric or non-woven fabric with an aggregate of non-combustible powder. Furthermore, it is essential that there are no voids in the aggregate of non-combustible powder that communicate with the outside. As a result, since air is not supplied to the fabric or non-woven fabric, non-combustibility is imparted to the combustible fabric or non-woven fabric, and not only does the fabric or non-woven fabric not burn, but also combustible substances due to thermal decomposition of the fabric or non-woven fabric are trapped in the film, preventing the spread of fire and suppressing the generation of harmful gases associated with the spread of fire, resulting in a fire prevention and non-combustible sheet. Fifthly, the cut sheet is also non-combustible. That is, even if the continuously manufactured sheet is non-combustible, since the uses of the cut sheet are extremely wide, it is essential that the cut sheet is also non-combustible. For this reason, even if a fabric or non-woven fabric appears on the cross-section of the cut sheet, it is essential that the fabric or non-woven fabric at the site excluding the end of the cut sheet is divided into innumerable pieces by the aggregation of powder, and there is no gap in the aggregation of powder communicating with the outside world. Thus, even if the cut sheet is exposed to an atmosphere where the fabric or non-woven fabric burns, the damage to the cut sheet remains at the fabric or non-woven fabric that appears on the cross-section, and the part excluding the cross-section of the cut sheet maintains non-combustibility. Sixthly, it has mechanical strength as a sheet. For this reason, it is essential that all the powders are joined by frictional pressure bonding at the part where the powders contact each other. Thus, the film composed of the aggregated joined powders has mechanical strength based on the bonding force between the powders, and the sheet joined by covering the entire fabric or non-woven fabric with the film has a certain mechanical strength. Seventhly, if the powder is a powder made of metal or alloy, the sheet becomes a conductive sheet, and if the powder is a powder made of metal oxide or nitride, the sheet becomes an insulating sheet. For this reason, it is essential that all adjacent powders are joined at the contact part. Thus, if the powder is a powder made of metal or alloy, a path for continuous electron movement is formed in the film. For this reason, the film has conductivity based on the conductivity of the powder. On the other hand, if the powder is a powder made of metal oxide or nitride, the film has insulation based on the resistivity of the powder. That is, the film is proportional to the resistivity of the metal oxide or nitride, inversely proportional to the cross-sectional area of the film, and proportional to the length of the film. For this reason, if the thickness of the film is thin, the insulation resistance of the film increases. Thus, no leakage current flows through the insulating sheet and the insulating sheet does not generate heat, so the insulating sheet does not deteriorate thermally over a long period. Eighth, the thickness of the film formed by the aggregation of powders joined by friction pressure welding continuously maintains a constant thickness. As a result, in the case of powders made of metal or alloy, a sheet with a preset conductivity is continuously manufactured. Also, in the case of powders made of metal oxide or nitride, a sheet with a preset insulation is continuously manufactured. Ninth, the sheet has water repellency that repels all liquids. As a result, the film becomes a corrosion-resistant sheet based on the corrosion resistance of the powder. Tenth, the sheet has heat resistance corresponding to the heat-resistant temperature of the powder. Also, the cut sheet also has heat resistance corresponding to the heat-resistant temperature of the powder. Eleventh, there are no restrictions on the material of the powder used when forming the film. As a result, the sheet has the properties of various powders and the sheet is used for various applications. Twelfth, there are no restrictions on the material or size of the fabric or non-woven fabric used. As a result, a general-purpose sheet that is lightweight and has no size restrictions can be formed. Thirteenth, the sheet can be manufactured by an inexpensive manufacturing method. As a result, the sheet is used for various applications. For this reason, it is essential that all processes in the process of manufacturing the sheet are simple and the materials used are inexpensive. Many of the 13 problems described above are solved by finding a method of joining a film composed of an aggregation of joined powders to a fabric or non-woven fabric, where powders are joined to each other at all contact parts where adjacent powders contact each other, and furthermore, overlapping powders are joined to each other at all contact parts. The problem to be solved in the present invention is to find a method for manufacturing a sheet that solves the above-described 13 problems.

Means for Solving the Problems

[0011] A manufacturing method for continuously manufacturing a sheet having a structure in which the whole of a fabric or non-woven fabric is covered with a film formed by an aggregation of one type of powder made of any of metal, alloy, metal oxide, or nitride having a micron size joined by friction pressure welding First, in a container that is wider in width than the width of the sheet to be manufactured and has a length that allows for the installation of the following plurality of cylindrical rollers, rotate at the same circumferential speed with a rotation time per revolution longer than 20 seconds, and provide a plurality of cylindrical rollers having the same length and the same diameter as the width of the container while spacing them apart from each other and arranging them parallel to the width of the container. The arrangement position of the plurality of cylindrical rollers in the container is such that the first roller is located at a height corresponding to the height where the topmost part contacts the fabric or non-woven fabric drawn from the roll of the fabric or non-woven fabric used in the second step, and is installed at a position more than 1 cm away from one side surface forming the width of the container. The second roller is installed at a position farther from one side surface forming the width of the container by the size of the first roller compared to the installation position of the first roller, and is installed at a position more than 1 cm away from the bottom surface of the container. The last roller is installed at a position more than 1 cm away from the other side surface forming the width of the container and at the same height as the height where the first roller is installed. The second-to-last roller is installed at a position farther from the other side surface forming the width of the container by the size of the last roller compared to the installation position of the last roller and at the same distance from the bottom surface of the container as the second roller. The remaining plurality of rollers are installed at the same distance from the bottom surface of the container as the second roller, between the second roller and the second-to-last roller, with a distance of not more than twice the diameter of the cylindrical roller between each roller, and are arranged at equal intervals. Next, for a collection of the powder consisting of one kind of powder made of any of the materials of metal, alloy, metal oxide, or nitride with a size in the micron range and having a weight greater than the weight required for continuously manufacturing the sheet, and for an alcohol with a viscosity at 20°C of 3 - 11 mPa·s, the smaller the size of the powder, the more asymmetric the shape of the powder, and the higher the hardness of the powder, the higher the viscosity of the alcohol used. The alcohol is filled into the container in an amount that forms a volume in which all the rollers except the first roller and the last roller are immersed, the alcohol is stirred, and a suspension is created in which the collection of the powder is dispersed in the alcohol.A first step of immersing all of the remaining rollers among the plurality of cylindrical rollers except the first roller and the last roller in the suspension; A fabric or non-woven fabric wound around a roll having the width of the sheet to be manufactured is set on a pay-off device of the roll, and the fabric or non-woven fabric is continuously drawn from the roll at a speed corresponding to the peripheral speed of the plurality of cylindrical rollers in the first step. Thereafter, the drawn fabric or the drawn non-woven fabric contacts the uppermost part of the first roller, and a side surface close to 1 / 4 of the first roller contacts the first roller and moves together with the first roller. Thereafter, the moving direction is changed downward and the fabric or non-woven fabric moves and is immersed in the suspension. Further, since the rotation direction of the second roller with which the fabric or non-woven fabric contacts is opposite to the rotation direction of the first roller, the fabric or non-woven fabric contacting the second roller contacts a side surface close to 1 / 4 of the second roller and moves together with the second roller. Thereafter, the moving direction is changed in a direction parallel to the bottom surface of the container and the fabric or non-woven fabric moves and sequentially contacts a plurality of rollers excluding the first roller, the second roller, and the last roller. Since the rotation direction of the plurality of rollers is the same as the rotation direction of the second roller, the fabric or non-woven fabric sequentially contacting the plurality of rollers advances in the suspension without changing the moving direction and contacts the second last roller. Since the rotation direction of the second last roller is the same as the rotation direction of the second roller, the fabric or non-woven fabric contacting the second last roller contacts a side surface close to 1 / 4 of the second last roller and moves together with the second last roller. Thereafter, the moving direction is changed upward and the fabric or non-woven fabric advances. After being pulled up from the suspension, the fabric or non-woven fabric contacts the last roller. Since the rotation direction of the last roller is opposite to the rotation direction of the second last roller, the fabric or non-woven fabric contacting the last roller contacts a side surface close to 1 / 4 of the last roller and moves together with the last roller. Thereafter, the moving direction is changed in the direction of the gap between the two work rolls constituting the multi-stage rolling mill used in the third step and the fabric or non-woven fabric moves. Such a series of treatments for the fabric or non-woven fabric is from the scene where the fabric or non-woven fabric drawn from the roll contacts the first roller,The process up to the scene where the fabric or the non-woven fabric contacts the last roller and changes the moving direction in the direction of the gap between the two work rolls constituting the multi-stage rolling machine and moves is implemented as a continuous process for the fabric or the non-woven fabric. This is the second step. First, two work rolls constituting a multi-stage rolling mill have, firstly, the same width wider than the width of the sheet to be manufactured, secondly, the same diameter smaller than 1 / 10 of the width of the sheet, thirdly, a gap is set as the thickness of the sheet to be created, fourthly, they rotate in opposite directions to each other at the same circumferential speed as the circumferential speed at which the plurality of rollers in the first step rotate, and fifthly, a multi-stage rolling mill having the two work rolls with five characteristics that are heated to a temperature 10 °C higher than the boiling point of the alcohol constituting the suspension in the first step is prepared. Next, the tip of the fabric or the non-woven fabric that has completed the treatment in the second step is inserted into the gap between the two work rolls. As a result, the tip of the fabric or the non-woven fabric is drawn into the gap between the two work rolls, and the fabric or the non-woven fabric continuously receives a compressive stress corresponding to the size of the gap between the two work rolls. At this time, first, alcohol vaporizes from the suspension evenly adhering to the fabric or the non-woven fabric, and the powder constituting the suspension overlaps and precipitates on the fabric or the non-woven fabric, and the fabric or the non-woven fabric is covered with the accumulation of the powder. Next, a compressive stress begins to be applied to the accumulation of the overlapping and precipitated powder and the fabric or the non-woven fabric. First, the surface layer of the accumulation of the powder collapses, and the surface layer of the accumulation of the powder precipitated at the end of the fabric or the non-woven fabric is such that the accumulation of the powder constituting the surface layer moves to the end and overlaps at the end, and the surface layer of the accumulation of the powder precipitated other than the end moves to the rear side of the gap between the two work rolls. Next, the compressive stress is applied to the accumulation of the powder and the fabric or the non-woven fabric, the accumulation of the powder is compressed, the fabric or the non-woven fabric is compressed and deformed, and further, it breaks due to the shear stress applied by the contacting powder, and the fabric or the non-woven fabric is divided. Furthermore, the powder moves to the broken part of the fabric or the non-woven fabric, the void of the fabric, or the void of the non-woven fabric, and the divided fabric or the divided non-woven fabric is covered with the accumulation of the powder. Furthermore, a compressive stress is applied to the accumulation of the powder, and the accumulation of the powder covering the divided fabric or the divided non-woven fabric is joined by frictional pressure contact at all contact parts where adjacent powders contact each other.The aggregate of powders joined by friction welding is joined to the divided fabric or the divided non-woven fabric by friction welding, covering the entire divided fabric or the divided non-woven fabric. Further, the aggregate of the overlapping powders is joined by friction welding at all contact portions where the powders contact each other. The aggregate of powders joined by friction welding is joined to the aggregate of powders joined by friction welding that covers the entire divided fabric or the divided non-woven fabric by friction welding. As a result, the entire divided fabric or the divided non-woven fabric is covered with a film made of the aggregate of powders joined by friction welding. From the phenomenon of vaporization of the alcohol, the phenomenon until the entire divided fabric or the divided non-woven fabric is covered with a film made of the aggregate of powders joined by friction welding occurs continuously in the aggregate of powders sandwiched between the gaps of the two work rolls and the fabric or the non-woven fabric. As a result, a sheet having a structure in which the entire divided fabric or the divided non-woven fabric is covered with the film is discharged from the gap between the two work rolls, and a third step of winding up the discharged sheet with a winding device rotating at the same speed as the rotational speed of the two work rolls is included. A method of continuously performing all the processes consisting of these three steps is a manufacturing method for continuously manufacturing a sheet having a structure in which the entire fabric or non-woven fabric is covered with a film formed by an aggregate of one type of powder made of any of metals, alloys, metal oxides, or nitrides having a micron size joined by friction welding.

[0012] By continuously performing all the processes in the three steps described below, a sheet having a structure in which the entire fabric or non-woven fabric is covered with a film formed by an aggregate of one type of powder made of any of metals, alloys, metal oxides, or nitrides having a micron size joined by friction welding is continuously manufactured. Here, the content of the processes in the three steps and the action and effect of the processes are explained. In the first step, first, when continuously manufacturing a sheet, the required weight of one type of powder made of any of metal, alloy, metal oxide or nitride is determined in advance, and the powder having a weight greater than the previously determined weight is put into a container whose lateral width is wider than the width of the sheet to be manufactured, and whose longitudinal width has a length where the following plurality of cylindrical rollers are provided. Further, alcohol having a viscosity of 3 - 11 mPa·s at 20°C is put into the container in an amount that forms a volume in which all of the remaining rollers except the first roller and the last roller among the following plurality of cylindrical rollers are immersed. After that, the alcohol is stirred to create a suspension in which aggregates of the powder are dispersed in the alcohol. Although there are a very large number of fine voids in fabrics and non-woven fabrics, since the alcohol constituting the suspension has a viscosity of 3 - 11 mPa·s at 20°C, the suspension fills the voids of the fabrics and non-woven fabrics, and the suspension adsorbs on the surfaces of the fabrics and non-woven fabrics. Also, in the container, a plurality of cylindrical rollers having the same circumferential speed and a rotation time per rotation longer than 20 seconds are spaced apart from each other and installed parallel to the lateral width of the container, with the same length and the same diameter as the lateral width of the container. The first roller is installed at a position more than 1 cm away from one side surface forming the lateral width of the container at a position where it contacts the fabric or non-woven fabric drawn out from the fabric or non-woven fabric wound in the second step at the top. The second roller is installed at a position more than 1 cm away from the bottom surface of the container and more than the size of the first roller away from the side surface forming the lateral width of the container compared to the installation position of the first roller. The last roller is installed at a position more than 1 cm away from the other side surface forming the lateral width of the container and at the same height as the height at which the first roller is installed. The second last roller is installed at a position more than the size of the last roller away from the other side surface forming the lateral width of the container compared to the installation position of the last roller and at the same distance from the bottom surface of the container as the second roller. The remaining plurality of rollers are installed at the same distance from the bottom surface of the container as the second roller, between the second roller and the second last roller, with a distance of not more than twice the diameter of the cylindrical roller, and each roller is installed at equal intervals. In addition, with regard to the weight-related components involved in the production of the sheet in the present invention, first, it is a method of continuously producing the sheet; second, the coating has airtightness to block gas; and third, the sheet has mechanical strength. First, in order to continuously produce the sheet, the moving speeds of the fabric or non-woven fabric described below are set to the same speed. That is, the speed at which the fabric or non-woven fabric is continuously pulled out from the web is continuously pulled out at a speed corresponding to the peripheral speed of a plurality of cylindrical rollers provided in the container, and the two work rolls constituting the multi-stage rolling mill are rotated in opposite directions at the same peripheral speed as the peripheral speed at which the plurality of cylindrical rollers rotate. Furthermore, the sheet discharged from the gap between the two work rolls needs to be wound up by a winding device that rotates at the same speed as the rotational speed of the two work rolls. For this reason, the speed at which the fabric or non-woven fabric is continuously pulled out from the web is set to a speed corresponding to the peripheral speed of the plurality of cylindrical rollers, the peripheral speed at which the two work rolls rotate is set to the same speed as the peripheral speed of the plurality of cylindrical rollers, and the rotational speed of the winding device for winding up the sheet is rotated at the same speed as the rotational speed of the two work rolls. Second, all the voids in the coating are confined inside the coating to form a coating without voids communicating with the outside world. For this purpose, the required number of powders are deposited overlappingly on the surface of the fabric or non-woven fabric, and further, the aggregates of the powders deposited overlappingly are evenly compressed, and it is necessary to join all the contact parts between adjacent powders by friction pressure welding. For this reason, it is necessary to ensure that the aggregate of powders and the fabric or non-woven fabric are in contact with two work rolls and further ensure the time for receiving the compression stress from the two work rolls. For this reason, the two work rolls are rotated at a slow peripheral speed with a time required for one rotation longer than 20 seconds, similar to a plurality of cylindrical rollers. Further, since the fabric or non-woven fabric moves slowly in the suspension, the suspension adheres evenly to the whole of the fabric or non-woven fabric with a thickness corresponding to the viscosity of alcohol. Since the powder has a specific shape, a specific particle size distribution, and a specific hardness, the amount of powder required to form a coating without voids communicating with the outside world and the appropriate gap between the two work rolls are determined in advance by repeated experiments for the powder used. Third, the coating composed of the aggregates of powders joined by friction pressure welding is joined by friction pressure welding at all the contact parts where adjacent powders contact each other, and also, the aggregates of the overlapping powders are joined by friction pressure welding at all the contact parts where the powders contact each other. For this reason, the coating has mechanical strength based on the bonding force between the powders. Therefore, the sheet has mechanical strength based on the bonding force between the powders. Next, the reason for giving a range to the viscosity of the alcohol constituting the suspension will be explained. When the suspension is adhered to a fabric or non-woven fabric and then the alcohol is vaporized, the powder deposits with the powder overlapping on the fabric or non-woven fabric. Further, the aggregate of the powder deposited by overlapping is compressed. At this time, the behavior of the powder to be compressed differs depending on the shape of the powder and also differs depending on the plastic deformation of the powder. That is, since there is a variation in the size of the powder, many voids are formed in the aggregate of the powder deposited by overlapping. Next, when the aggregate of the powder is compressed, the powder moves so as to fill the voids in the aggregate of the powder, especially for the powder having a shape with excellent symmetry. However, not all the voids are filled by the movement of the powder. After that, adjacent powders are joined by friction pressure welding at all contact portions where they contact each other. However, not all the voids in the aggregate of the powders joined by friction pressure welding can be confined inside the aggregate of the joined powders. Therefore, the powders overlapped are joined by friction pressure welding, and all the voids in the aggregate of the powders joined by friction pressure welding can be confined inside the aggregate of the joined powders. On the other hand, when the aggregate of the powder is compressed, the powder moves so as to fill the voids in the aggregate of the powder, but for the powder having a shape with inferior symmetry, the voids in the aggregate of the powder are not filled by the powder. Therefore, for the powder having a shape with inferior symmetry, more powders are overlapped and more powders are joined by friction pressure welding, so that all the voids in the aggregate of the powders joined by friction pressure welding can be confined inside the aggregate of the joined powders. Therefore, when using a powder having a shape with inferior symmetry, an alcohol with a high viscosity is used. On the other hand, there are powders with relatively low hardness that undergo plastic deformation under compressive stress. That is, when compressive stress is evenly applied to a collection of powders, the powders undergo plastic deformation, and the plastically deformed powders fill adjacent voids, reducing the voids. However, not all voids are filled by the plastic deformation of the powders. Therefore, the overlapping powders are joined by friction pressure welding, and all the voids in the collection of powders joined by friction pressure welding are confined inside the collection of joined powders. Thus, when using powders with a large ratio of plastic deformation under compressive stress, compared to powders with a small ratio of plastic deformation under compressive stress, the number of powders to be stacked is smaller, but by stacking the powders and joining the powders together by friction pressure welding, all the voids in the collection of powders joined by friction pressure welding are confined inside the collection of joined powders. Therefore, when using powders with a large ratio of plastic deformation under compressive stress, an alcohol with a lower viscosity is used compared to when using powders with a small ratio of plastic deformation under compressive stress. Furthermore, the powders are micron-sized and light in weight, but the size of the powders varies greatly depending on the type of powder. On the other hand, the surface area of the powders corresponds to the size of the powders. Therefore, in order to join a collection of overlapping powders by friction pressure welding and confine all the voids in the collection of powders joined by friction pressure welding inside the collection of joined powders, it is necessary to increase the number of overlapping powders for powders with a smaller size. For this reason, an alcohol with a higher viscosity is used for powders with a smaller size. As a result, the thickness of the suspension adsorbed on the surface of the fabric or non-woven fabric becomes thicker for powders with a smaller size. As described above, the behavior of the powders to be compressed varies depending on the shape of the powders and also on the plastic deformation of the powders. Therefore, for powders with inferior symmetry, for powders with higher hardness, and for powders with a smaller size, the thickness of the suspension adhered to the entire fabric or non-woven fabric is increased. Also, according to the hardness of the powders, the gap between the two work rolls is changed and the compressive stress applied is changed. For these reasons, the viscosity of the alcohol is changed depending on the symmetry of the powders used, the hardness of the powders used, and the size of the powders. Also, according to the hardness of the powders used, the gap between the two work rolls is changed and the magnitude of the compressive stress applied to the collection of powders is changed. Incidentally, there are 17 types of alcohols having a viscosity of 3 to 11 mPa·s at 20°C as follows. 1-Butanol CH3(CH2)3OH has a viscosity of 3.0 mPa·s at 20°C and a boiling point of 117°C. 1-Pentanol CH3(CH2)4OH has a viscosity of 3.3 mPa·s at 20°C and a boiling point of 138°C. 2-Pentanol CH3(CH2)2CH(OH)CH3 has a viscosity of 3.5 mPa·s at 20°C and a boiling point of 119°C. 3-Methyl-1-butanol (CH3)2CH(CH2)2OH has a viscosity of 3.7 mPa·s at 20°C and a boiling point of 131°C. 2-Methyl-2-butanol CH3CH2C(CH3)2OH has a viscosity of 3.8 mPa·s at 25°C and a boiling point of 103°C. 2-Butanol CH3CHOHCH2CH3 has a viscosity of 3.9 mPa·s at 20°C and a boiling point of 99°C. 2-Heptanol CH3(CH2)4CHOHCH3 has a viscosity of 4.0 mPa·s at 20°C and a boiling point of 159°C. Isobutyl alcohol (CH3)2CHCH2OH has a viscosity of 4.0 mPa·s at 20°C and a boiling point of 108°C. 2-Methyl-1-butanol CH3CH2CH(CH3)CH2OH has a viscosity of 5.1 mPa·s at 20°C and a boiling point of 128°C. 1-Hexanol CH3(CH2)5OH has a viscosity of 5.3 mPa·s at 20°C and a boiling point of 157°C. 1-Heptanol CH3(CH2)6OH has a viscosity of 5.8 mPa·s at 20°C and a boiling point of 176°C. 2-Octanol CH3(CH2)5CH(OH)CH3 has a viscosity of 6.2 mPa·s at 20°C and a boiling point of 178°C. 3-Pentanol (C2H5)2CHOH has a viscosity of 6.5 mPa·s at 20°C and a boiling point of 116°C. 1-Octanol CH3(CH2)7OH has a viscosity of 7.3 mPa·s at 20°C and a boiling point of 194°C. 2-Ethyl-1-hexanol CH3(CH2)3CH(C2H5)CH2OH has a viscosity of 9.8 mPa·s at 20°C and a boiling point of 185°C. Isooctyl alcohol (CH3)2CH(CH2)5OH has a viscosity of 10.6 mPa·s at 20°C and a boiling point of 188°C. 1-Nonanol CH3(CH2)8OH has a viscosity of 10.8 mPa·s at 20°C and a boiling point of 212°C. Therefore, when any one of these 17 alcohols is used as the alcohol having a viscosity of 3 - 11 mPa·s at 20°C described in paragraph 11, and all the treatments of the three steps described in paragraph 11 are continuously carried out in order, a sheet having a structure in which the entire surface of the fabric or non-woven fabric is covered with a film formed by an aggregate of powders joined by friction pressure welding is continuously manufactured. Since the boiling points of these 17 alcohols are 212°C or lower, in the third step described in paragraph 11, the temperature for raising the temperature of the two work rolls of the multi-stage rolling mill is low, and the treatment of the third step is easy. In the second step, first, a fabric or non-woven fabric having the width of the sheet to be manufactured and wound into a roll is prepared and set on a drawing device. Next, the fabric or non-woven fabric is continuously drawn from the roll at a speed corresponding to the peripheral speed of the plurality of cylindrical rollers in the first step. Further, the drawn fabric or non-woven fabric contacts the uppermost part of the first roller and moves along the side surface close to 1 / 4 of the first roller in contact with the first roller. Then, the moving direction is changed downward and the fabric or non-woven fabric moves and is immersed in the suspension, and further contacts the second roller. Since the rotation direction of the second roller is opposite to that of the first roller, the fabric or non-woven fabric in contact with the second roller moves along the side surface close to 1 / 4 of the second roller in contact with the second roller. Then, the moving direction is changed in a direction parallel to the bottom surface of the container and the fabric or non-woven fabric moves and contacts a plurality of rollers except the second roller and the last roller in sequence. Since the rotation directions of the plurality of rollers are the same as that of the second roller, the fabric or non-woven fabric in contact with the plurality of rollers in sequence advances in the suspension without changing the moving direction and contacts the second last roller. Since the rotation direction of the second last roller is the same as that of the second roller, the fabric or non-woven fabric in contact with the second last roller moves along the side surface close to 1 / 4 of the second last roller in contact with the second last roller. Then, the moving direction is changed upward and the fabric or non-woven fabric advances, and after being pulled up from the suspension, it contacts the last roller. Since the rotation direction of the last roller is opposite to that of the second last roller, the fabric or non-woven fabric in contact with the last roller moves along the side surface close to 1 / 4 of the last roller in contact with the last roller. Then, the moving direction is changed in the direction of the gap between the two work rolls constituting the multi-stage rolling mill used in the third step and the fabric or non-woven fabric moves. Note that when the fabric or non-woven fabric horizontally moves at a slow speed corresponding to the peripheral speed of the plurality of cylindrical rollers over the distance from the second roller to the second last roller, the powder constituting the suspension adsorbed on the surface of the fabric or non-woven fabric is micron-sized and lightweight, so a load is applied to the powder.Due to this load, depending on the symmetry of the powder's shape, the powder rearranges in the suspension. Also, the suspension adsorbs to the ends of the fabric or non-woven fabric, covering the ends with the suspension, and thereby covering the entire fabric or non-woven fabric with the suspension. The treatment for the fabric or non-woven fabric described above is carried out as a continuous treatment for the fabric or non-woven fabric because the moving speed related to the fabric or non-woven fabric is the same in the process from the scene where the fabric or non-woven fabric drawn from the workpiece contacts the first roller to the scene where the fabric or non-woven fabric contacts the last roller and moves in the direction of the gap between the two work rolls constituting the multi-stage rolling mill. The third step is, first, to prepare a multi-stage rolling mill having two work rolls that constitute the multi-stage rolling mill, which, first, have the same width wider than the width of the sheet to be manufactured, second, have the same diameter smaller than 1 / 10 of the width of the sheet, third, have a gap set as the thickness of the sheet to be created, fourth, rotate in opposite directions at the same peripheral speed as the peripheral speed at which the plurality of rollers in the first step rotate, and fifth, heat up to a temperature 10°C higher than the boiling point of the alcohol constituting the suspension in the first step. The reason for using a multi-stage rolling mill is that although the width of the two work rolls is wider than the width of the sheet to be manufactured, the diameter of the two work rolls is smaller than 1 / 10 of the width of the sheet, so when the two work rolls are rotated in opposite directions, the two work rolls elastically deform. A multi-stage rolling mill is used to suppress this elastic deformation of the two work rolls by the rotation of other backup rolls. As a result, a compressive stress applied from the gap between the two work rolls is continuously applied as a constant compressive stress to the fabric or non-woven fabric and the collection of powder. For example, there is a 12-stage rolling mill as the multi-stage rolling mill. Also, with the multi-stage rolling mill, it is possible to manufacture thin sheets with a thickness of up to 10 μm for various metals and various alloys. Furthermore, since the rotational speed of the two work rolls is a peripheral speed with a time required for one rotation longer than 20 seconds, the contact time between the two work rolls, the fabric or non-woven fabric, and the collection of powder can be ensured, and the collection of powder deposited overlapping on the fabric or non-woven fabric does not fall off from the fabric or non-woven fabric. Next, the tip of the fabric or non-woven fabric that has completed the second process is inserted into the gap between the two work rolls. As a result, the tip of the fabric or non-woven fabric is drawn into the gap between the two work rolls, and a compressive stress having a magnitude corresponding to the gap between the two work rolls is continuously received by the powder aggregate and the fabric or non-woven fabric from the gap between the two work rolls. At this time, first, when the fabric or non-woven fabric that has completed the second process approaches the gap between the two work rolls, alcohol vaporizes from the suspension adhering to the fabric or non-woven fabric, and powder overlaps and precipitates at the site where the alcohol has vaporized. Next, compressive stress begins to be applied to the aggregate of powder that has overlapped and precipitated and the fabric or non-woven fabric. The surface layer of the aggregate of powder collapses first, and the aggregate of powder precipitated at the end of the fabric or non-woven fabric further moves to the end and overlaps. The surface layer of the majority of the aggregates of powder precipitated outside the end moves to the rear side of the gap between the two work rolls. After that, compressive stress is applied to the aggregate of powder and the fabric or non-woven fabric. At this time, the fabric or non-woven fabric undergoes compressive deformation and is further broken by the shear stress applied by the contacted powder. On the other hand, since the powder is as small as micron size and the fabric or non-woven fabric is covered with the aggregate of powder, an extremely large amount of powder contacts the fabric or non-woven fabric, and an extremely large number of breakage points are formed in the fabric or non-woven fabric. As a result, the fabric or non-woven fabric is divided. Further, since compressive stress is applied to the aggregate of powder, the powder moves into the broken parts of the fabric or non-woven fabric, the voids of the fabric, or the voids of the non-woven fabric, and the divided fabric or non-woven fabric is filled with powder. That is, as described in the first paragraph, the fabric has extremely many voids on its surface. However, since compressive stress is applied to the aggregate of powder, the powder moves and extremely many voids are filled with powder. Also, as described in the first paragraph, the non-woven fabric is porous and has a large number of voids. However, since compressive stress is applied to the aggregate of powder, the powder moves and the voids on the front and back surfaces of the non-woven fabric are filled with powder. Further, compressive stress continues to be applied to the aggregate of powder, and the aggregate of powder covering the divided fabric or divided non-woven fabric joins the powders together by friction and pressure bonding at all the contact parts where the adjacent powders contact each other. The aggregate of powder joined by friction and pressure bonding covers the entire divided fabric or divided non-woven fabric. Further, the overlapping aggregates of powder join the powders together by friction and pressure bonding at all the contact parts where the powders contact each other, and join by friction and pressure bonding to the aggregate of powder joined by friction and pressure bonding that covers the entire divided fabric or divided non-woven fabric.As a result, the entire cut fabric or cut nonwoven fabric is covered with a film composed of an aggregate of powder joined by friction welding. From the phenomenon of vaporization of such alcohol, the phenomenon until the entire cut fabric or cut nonwoven fabric is covered with a film composed of an aggregate of powder joined by friction welding occurs continuously with respect to the aggregate of powder sandwiched between the gaps of the two work rolls and the fabric or nonwoven fabric. As a result, a sheet having a structure in which the entire cut fabric or cut nonwoven fabric is covered with a film is discharged from the gap between the two work rolls, and the discharged sheet is wound up by a winding device rotating at the same speed as the rotational speed of the two work rolls. As a result, since the moving speed of the fabric or nonwoven fabric from when it is drawn out from the workpiece to when the sheet is wound up by the winding machine is the same, the sheet is continuously manufactured. Note that the aggregate of powder joined by friction welding is confined inside the aggregate of powder that has joined all the voids, and the aggregate of powder is formed as a film having no voids communicating with the outside. Note that the film composed of an aggregate of powder is a film in which aggregates of micron-sized powder overlap and join, and the thickness of the joined aggregate of powder is thinner than 0.25 mm. That is, the thinner the thickness of the film composed of the aggregate of powder joined by friction welding, the less the amount of powder used, so that the sheet can be manufactured at low cost, the weight of the sheet is reduced, the cutting of the sheet becomes easier, and if the powder is plastically deformable, the bending process of the cut sheet becomes easier. However, since the powder has a specific shape, a specific particle size distribution, and a specific hardness, the amount of powder required to form a film having no voids communicating with the outside and the appropriate gap between the two work rolls were determined experimentally by repeatedly performing experiments on the powder used. By continuously performing all the processes of these three steps in order, the sheet is continuously manufactured. As a result, a sheet having a structure in which the entire fabric or nonwoven fabric is covered with a film formed by an aggregate of one type of powder made of any of metals, alloys, metal oxides, or nitrides having a micron size joined by friction welding is continuously manufactured. The sheet thus manufactured exhibits the following effects and solves the 13 problems described in paragraph 10. First, the sheet can be continuously manufactured. That is, the circumferential speed at which a plurality of cylindrical rollers provided in the container rotate at the same speed is set to a speed corresponding to the speed at which the fabric or non-woven fabric is continuously pulled out from the web. Further, the circumferential speed at which the two work rolls of the multi-stage rolling mill rotate is set to the same speed as the circumferential speed at which the plurality of cylindrical rollers rotate. Also, a winding device that rotates at the same speed as the rotational speed of the two work rolls winds up the sheet discharged from the gap between the two work rolls. Therefore, the moving speed related to the fabric or non-woven fabric is the same, and the sheet is continuously manufactured. Second, the sheet can be cut. That is, the film composed of an aggregate of powders joined by friction pressure welding is a film in which aggregates of micron-sized powders overlap and are joined, and the thickness of the joined aggregate of powders is thinner than 0.25 mm. For this reason, even if the powder has a high hardness, the sheet can be cut. As a result, it can be processed into sheets of various sizes and shapes. Third, the cut sheet can be pressure-bonded to substrates or parts made of various materials. That is, when the sheet is placed on the surface of a substrate or part made of various materials and shapes and the surface of the sheet is compressed, the convex portions of the unevenness on the surface of the sheet come into contact with the surface of the substrate or part, and the sheet is joined to the surface of the substrate or part by the frictional heat generated at this contact portion. Fourthly, the sheet is incombustible. That is, in the third step of paragraph 11, when the alcohol vaporizes, a collection of powder that overlaps without gaps is deposited on the fabric or non-woven fabric. At this time, since there is variation in the size of the powder, and depending on the symmetry of the shape of the powder, many voids are formed in the collection of powder that has overlapped and been deposited. Next, when the collection of powder is compressed, the powder having a shape with better symmetry moves to fill the voids in the collection of powder. However, not all voids are filled by the movement of the powder. After that, adjacent powders are joined by friction pressure welding at all contact parts where they come into contact. However, not all voids in the collection of powder joined by friction pressure welding can be confined inside the joined collection of powder. Therefore, by joining overlapping powders by friction pressure welding and further joining the collection of powder joined by the above-mentioned friction pressure welding by friction pressure welding, all voids in the collection of powder joined by friction pressure welding can be confined inside the joined collection of powder. On the other hand, the more the powder has a shape with inferior symmetry, when the collection of powder is compressed, the powder moves to fill the voids in the collection of powder, but because the powder has inferior symmetry, many voids in the collection of powder cannot be filled with powder. Therefore, the more the powder has a shape with inferior symmetry, by overlapping more powder and joining more powders by friction pressure welding, all voids in the collection of powder joined by friction pressure welding can be confined inside the joined collection of powder. Furthermore, the size of the powder varies greatly depending on the type of powder. Since the surface area of the powder depends on the size of the powder, when the size of the powder is small, by overlapping more powder and joining more powders by friction pressure welding, all voids in the collection of powder joined by friction pressure welding can be confined inside the joined collection of powder. There is also a powder with low hardness that is prone to plastic deformation under compressive stress. That is, when compressive stress is evenly applied to a collection of powders, the powders undergo plastic deformation, and the plastically deformed powders fill the adjacent voids, reducing the voids. However, not all voids are filled due to the plastic deformation of the powders. Therefore, the overlapping powders can be joined by friction pressure welding, and all the voids in the collection of powders joined by friction pressure welding can be confined inside the collection of the joined powders. As a result, all the voids in the collection of powders joined by friction pressure welding are confined inside the collection of the joined powders. Therefore, the film composed of the collection of the joined powders provides airtightness for blocking gas against fabrics or nonwoven fabrics. As a result, the flammable fabrics or nonwoven fabrics are made nonflammable, and not only do the fabrics or nonwoven fabrics not burn, but also the combustible substances generated when the fabrics or nonwoven fabrics thermally decompose are not discharged to the outside. Therefore, the sheet acts as a nonflammable sheet that prevents the spread of fire and also acts as a sheet that suppresses the generation of harmful gases associated with the spread of fire. Fifthly, the cut sheet is also incombustible. That is, in the third step of paragraph 11, when a compressive stress is applied to the powder aggregate and the fabric or non-woven fabric, the fabric or non-woven fabric undergoes compressive deformation. Further, the powder in contact with the fabric or non-woven fabric applies a shear stress to the fabric or non-woven fabric, and the location where the shear stress is applied breaks. On the other hand, since the powder is as small as the micron size and the entire fabric or non-woven fabric is covered with the powder aggregate, an extremely large amount of powder comes into contact with the fabric or non-woven fabric, and an extremely large number of breakage points are formed in the fabric or non-woven fabric. As a result, the fabric or non-woven fabric is divided. Also, the powder aggregate covering the entire divided fabric or divided non-woven fabric is joined by friction and pressure bonding between the powders at all the contact parts where the adjacent powders contact each other, and the powder aggregate joined by friction and pressure bonding covers the entire divided fabric or divided non-woven fabric. Further, the overlapping powder aggregates are joined by friction and pressure bonding between the powders at all the contact parts where the powders contact each other, and are joined by friction and pressure bonding to the powder aggregate joined by friction and pressure bonding that covers the entire divided fabric or divided non-woven fabric. As a result, the entire divided fabric or divided non-woven fabric is covered with a film composed of a powder aggregate joined by friction and pressure bonding. There are no voids communicating with the outside world in this film. Therefore, even if a part of the divided fabric or divided non-woven fabric appears on the cross-section of the cut sheet and the fabric or non-woven fabric is exposed to an atmosphere where it can burn, since the powder aggregate is firmly joined to the divided fabric or divided non-woven fabric by friction and pressure bonding, the burning of the fabric or non-woven fabric remains in a part of the divided fabric or divided non-woven fabric that appears on the cross-section of the cut sheet. Therefore, the cut sheet is incombustible. Sixthly, it has mechanical strength as a sheet. That is, in the third step of paragraph 11, when the powder aggregate is compressed, the powders are joined by friction and pressure bonding at all the contact parts where the adjacent powders contact each other, and the joined powder aggregate forms a film. Also, a compressive stress is evenly applied to the entire film, and the film is joined to the entire divided fabric or divided non-woven fabric by friction and pressure bonding. Therefore, the film has the bonding force between the powders, and the sheet covered with the film has mechanical strength as a sheet. Seventhly, if the powder is a powder made of metal or alloy, the sheet will be a conductive sheet, and if the powder is a powder made of metal oxide or nitride, the sheet will be an insulating sheet. That is, a film composed of an aggregate of powders joined by friction pressure welding covers the entire divided fabric or divided non-woven fabric. Therefore, if it is a powder made of metal or alloy, a path through which current continuously flows is formed in the film. For this reason, the sheet has conductivity based on the conductivity of the powder made of metal or alloy. Also, if it is a powder made of metal oxide or nitride, the film forms an insulating film. Therefore, the resistance of the sheet is proportional to the resistivity of the metal oxide or nitride, inversely proportional to the cross-sectional area of the film, and proportional to the length of the film. Since the thickness of the film is extremely thin, the insulation resistance of the sheet is large. Eighthly, since a plurality of rollers from the second roller to the second last roller continuously stir the suspension, the dispersion state of the powder in the suspension does not change. Therefore, since the fabric or non-woven fabric passes through the constantly stirred suspension at a low speed, the volume ratio occupied by the powder in the suspension adsorbed on the fabric or non-woven fabric does not change. Also, the gap between the two work rolls does not change. As a result, in the case of a powder made of metal or alloy, a sheet having a preset conductivity is continuously manufactured. Also, in the case of a powder made of metal oxide or nitride, a sheet having a preset insulation is continuously manufactured. Ninthly, the sheet has water repellency that repels all liquids. That is, a film formed by an aggregate of powders joined by friction pressure welding covers the entire divided fabric or divided non-woven fabric. Since the surface of this film is composed of an aggregate of powders joined by friction pressure welding, the surface of the film has water repellency that repels all liquids due to the surface tension of the liquid. As a result, the sheet acts as a corrosion-resistant sheet based on the corrosion resistance of the powder. On the other hand, since powders made of metal oxide or nitride are more corrosion-resistant than powders made of metal or alloy, a sheet composed of an aggregate of powders made of metal oxide or nitride acts as an even more excellent corrosion-resistant sheet. Tenthly, the sheet has heat resistance corresponding to the heat-resistant temperature of the powder. That is, the film formed by the aggregation of the powder joined by friction pressure welding covers the entire divided fabric or divided non-woven fabric. This film has heat resistance corresponding to the heat-resistant temperature of the powder. Note that most of the heat-resistant temperatures of the powder are significantly higher than the thermal decomposition temperature of the fabric or non-woven fabric. Therefore, when the temperature of the film rises to a temperature equal to or higher than the temperature at which the fabric or non-woven fabric decomposes, the fabric or non-woven fabric decomposes, but the decomposed substances are confined within the film. For this reason, even when the temperature of the film rises to a temperature equal to or higher than the temperature at which the fabric or non-woven fabric decomposes, the film is non-combustible. On the other hand, since the powder made of metal oxide or nitride is more heat-resistant than the powder made of metal or alloy, the sheet covered with the film formed by the aggregation of the powder made of metal oxide or nitride acts as a sheet with even better heat resistance. Also, since only a part of the fabric or non-woven fabric appearing on the cut surface of the cut sheet burns out, the cut sheet also has heat resistance corresponding to the heat-resistant temperature of the powder. Eleventhly, there are no material restrictions on the powder used when forming the sheet. That is, since a film is formed by applying compressive stress to the aggregation of the powder and joining all the contact parts where adjacent powders come into contact by friction pressure welding, there are no material restrictions on the powder used when forming the film. As a result, the sheet has the inherent properties of the powder constituting the film. On the other hand, the powder made of any of the materials of metal, alloy, metal oxide or nitride has unique properties for each material of the powder. Therefore, the sheet has various properties of the powder and can be used for extremely wide applications. Twelfthly, the fabric or non-woven fabric for joining the aggregation of the powder joined by friction pressure welding has no restrictions on the material or size. As a result, a lightweight and versatile sheet can be formed. Thirteenthly, the sheet can be manufactured by an inexpensive manufacturing method. That is, all the processes of the three steps described in paragraph 11 are extremely simple processes. In addition, the materials used are powder made of any of metals, alloys, metal oxides or nitrides with a size in the micron range, which are general-purpose industrial materials, cloth or non-woven fabric, which are extremely inexpensive industrial products, and alcohol, which is a general-purpose organic solvent. Therefore, the sheet can be manufactured at low cost. As a result, the sheet can be used for various applications. As described above, the method for manufacturing the sheet of the present invention satisfies the 13 requirements described in paragraph 10. For this reason, all the problems of the 13 items described in paragraph 10 are solved. Note that, as described in paragraph 1, cloth is made by weaving warp threads and weft threads made of natural fibers or chemical fibers into a fabric, and there are three types of weaving methods: plain weave, twill weave, and satin weave. Plain weave is the simplest manufacturing method in which warp threads and weft threads cross alternately, and since the front and back fabrics have the same weaving method, it is strong against friction. Therefore, it is suitable for making thin and light fabrics. Twill weave is a manufacturing method in which warp threads cross over a plurality of weft threads and are woven up. Although the fabric tends to be hard in plain weave, the fabric becomes softer in twill weave. Satin weave, also called sateen, is a weaving method in which the intersection points of warp threads and weft threads are made as inconspicuous as possible, and warp threads or weft threads are floated long on the surface of the fabric. It is appropriate to use a cloth made of a fabric used in the present invention, and a cloth made of a cheaper plain weave or twill weave is sufficient, rather than a more expensive cloth made of satin weave. In addition, the cloth has extremely many concave portions and voids on the surface, and the extremely many concave portions and voids serve as means for supporting the aggregation of fine powder in the present invention. Therefore, the cloth is suitable as a frame for supporting the aggregation of powder. In addition, as described in one paragraph, a non-woven fabric is a non-woven cloth-like material. Fibers are accumulated in a certain direction or randomly and chemically bonded with an adhesive resin, or mechanically intertwined, or intertwined with a water flow under pressure, or bonded with heat-fused fibers to make it. Therefore, it is porous and has air permeability, filtration property, and moisture retention property. Accordingly, since the non-woven fabric can form fibers into a sheet as they are, there is no need to spin fibers like a woven fabric or a knitted fabric. For this reason, it can be manufactured at a lower cost than a woven fabric or a knitted fabric. In addition, there are extremely many voids in the non-woven fabric, and the extremely many voids serve as a means for supporting the aggregation of fine powder in the present invention. Therefore, the non-woven fabric is suitable as a frame for supporting the aggregation of powder. Note that natural fibers, chemical fibers, and glass fibers are used as raw materials for the non-woven fabric.

[0013] The method of cutting the sheet manufactured by the method described in paragraph 11 into a predetermined shape and joining the cut sheet to a predetermined position on the surface of the base material or the component is The method of continuously manufacturing a sheet by the method described in paragraph 11, cutting the sheet into a predetermined shape, overlapping the cut sheet at a predetermined position on the surface of the base material or the component, and further uniformly compressing the entire surface of the cut sheet. As a result, the convex portions of the unevenness on the surface of the cut sheet come into contact with the surface of the base material or the component to which the cut sheet is overlapped, and further, frictional heat is generated at the contact portion, and the contact portions are joined by the frictional heat, and the cut sheet is joined to a predetermined position on the surface of the base material or the component. This is a method of cutting the sheet manufactured by the method described in paragraph 11 into a predetermined shape and joining the cut sheet to a predetermined position on the surface of the base material or the component.

[0014] That is, the film composed of a collection of powders joined by friction welding is a film formed by overlapping micron-sized powder collections and joined, and the thickness of the joined powder is less than 0.25 mm. Therefore, even if the powder material is an alloy or metal oxide with high hardness, the sheet can be cut. As a result, it can be processed into sheets of various sizes and shapes. Note that since the thickness of the manufactured sheet is the gap between two work rolls, the thickness of the sheet to be manufactured can be set in advance. On the other hand, since the cut sheet is covered with a film composed of a collection of powders joined by friction welding, the surface of the cut sheet has irregularities close to the size of the joined powder and irregularities on the surface of the powder that appear on the surface of the cut sheet. Therefore, when the cut sheet is overlapped at a predetermined position on the surface of the base material or component and the entire surface of the cut sheet is uniformly compressed, the convex portions of the irregularities on the surface of the cut sheet come into contact with the surface of the base material or component. Furthermore, frictional heat is generated at the contact portion, and the contact portions are joined by this frictional heat. As a result, the cut sheet is joined to a predetermined position on the surface of the base material or component. Note that the convex portions of the irregularities on the surface of the cut sheet are composed of convex portions of irregularities close to the size of the joined powder and convex portions of irregularities on the surface of the powder that appear on the surface of the cut sheet. Therefore, these convex portions are extremely numerous, and the cut sheet is joined to the surface of the base material or component by these extremely many convex portions, so that the cut sheet is firmly joined to a predetermined position on the surface of the base material or component. In addition, the frictional heat generated at the contact portion on the surface of the base material or component is generated in a short time and disappears in a short time. Furthermore, the area of the contact portion where the frictional heat is generated is extremely narrow. Therefore, even for a base material or component made of a material with low heat resistance such as a synthetic resin, the cut sheet can be joined to a predetermined position on the surface of the base material or component by friction welding. As a result, the cut sheet can be joined to a predetermined position on the surface of a base material or component made of various materials, and various properties of the powder can be imparted to the predetermined position of the base material or component. Although the fabric or nonwoven fabric may appear on the cross section of the cut sheet, the fabric or nonwoven fabric inside the sheet is divided into countless pieces by a collection of powder particles bonded by friction welding, and furthermore, there are no voids communicating with the outside world in the collection of powder particles bonded by friction welding. Therefore, even if the fabric or nonwoven fabric appears on the cross section of the cut sheet and is exposed to a burning atmosphere, the burn damage of the fabric or nonwoven fabric is limited to the fabric or nonwoven fabric that appears on the cross section of the cut sheet, and noncombustibility is maintained in areas other than the cross section of the cut sheet.

[0015] A method for continuously producing a sheet having a structure in which a woven fabric or nonwoven fabric is entirely covered with a coating formed by an aggregate of powder particles bonded by friction welding as described in paragraph 11, comprising the steps of: The powder described in paragraph 11 is a powder having a spherical, granular or agglomerated shape, and a method of using the powder described in paragraph 11 and carrying out all of the three steps described in paragraph 11 in sequence is a manufacturing method for continuously producing a sheet having a configuration in which a woven fabric or nonwoven fabric is entirely covered with a coating formed by an aggregate of powder particles bonded by friction welding described in paragraph 11.

[0016] There are eight types of powder shapes made of micron-sized metals, alloys, metal oxides, or nitrides, as described below. First, there are powders having a spherical, granular, or lump-like shape; second, there are powders having a columnar, rod-like, needle-like, or fibrous shape; third, there are powders having a horn-like or horn-like shape; fourth, there are powders having a spongy shape; fifth, there are powders having a sponge-like shape; sixth, there are powders having a dendritic shape with many voids; seventh, there are powders having a teardrop-like or spindle-like shape; and eighth, there are powders having a plate-like, flake-like, or scale-like shape with a large aspect ratio. The shape of such powders is uniquely formed depending on the method of producing the powder. The aspect ratio of the powder is the ratio of the major axis to the thickness of the powder. Therefore, powders having a plate-like, flake-like, or scale-like shape have a larger aspect ratio than powders having other shapes. On the other hand, the film formed by the agglomeration of powders joined by friction welding in the present invention is a film formed by the overlapping and joining of micron-sized powder agglomerations, and the thickness of the joined powder agglomeration is thinner than 0.25 mm. Therefore, the sheet can be cut, which is the second property described in paragraph 12. On the other hand, for the film formed by the overlapping and joining of powder agglomerations to have the airtightness of blocking gas, which is the fourth property described in paragraph 12, the shape of the powder used is restricted. That is, by the treatment of the second step described in paragraph 11, the suspension adheres evenly to the entire fabric or non-woven fabric. Further, in the third step described in paragraph 11, after the alcohol vaporizes from the suspension, the agglomeration of powders deposited overlapping on the fabric or non-woven fabric is compressed. At this time, the more excellent the symmetry of the powder shape, the more the powder agglomeration is compressed, the powder moves, and the voids in the powder agglomeration are filled. Also, the lower the hardness of the powder, the more the powder undergoes plastic deformation, the plastically deformed powder fills the adjacent voids, and joins with the adjacent powder by friction welding. Further, the larger the size of the powder, the larger the surface area of the powder. Therefore, the larger the size of the powder, the smaller the number of powders required to fill the voids in the powder agglomeration. On the other hand, all the contact parts where adjacent powders contact each other are joined by friction welding. Also, the overlapping powder agglomerations are joined by friction welding. If all the voids are enclosed inside the agglomeration of powders joined by this friction welding, the film composed of the joined powder agglomerations has no voids communicating with the outside and has airtightness to block gas. On the other hand, powders with more excellent symmetry are less likely to undergo plastic deformation, and powders with high hardness and symmetry are even less likely to undergo plastic deformation. Therefore, it is necessary to increase the number of overlapping powder agglomerations. Therefore, the number of overlapping powders required for the film to have airtightness to block gas varies depending on the symmetry of the powder shape, the hardness of the powder, and the size of the powder. That is, powders with excellent symmetry, low hardness, and large size can relatively require fewer overlapping powders. By the way, as mentioned above, there are eight types of shapes of powders made of any of the materials of metals, alloys, metal oxides, and nitrides with a size of microns, and the most symmetrical shapes are spherical, granular, and lumpy. Meanwhile, in the second step described in paragraph 11, the cloth or nonwoven fabric pulled out from the roll moves horizontally in the suspension at a slow speed for a distance from the second roller to the penultimate roller. At this time, the powder constituting the suspension adsorbed on the surface of the cloth or nonwoven fabric is small and lightweight in the size of microns, so a load is applied to the powder due to the movement of the cloth or nonwoven fabric. This load causes the powder to rearrange in the suspension according to the symmetry of the powder shape. At this time, since the powder has a variation in size, the powder is accompanied by alcohol, and the powder overlaps with the alcohol to fill the gaps, increasing the accumulation density of the powder. Furthermore, if there are gaps in the powder mass, powder smaller than the gaps will enter the gaps and fill them. Therefore, the powder mass with the most symmetrical shape among the eight types of powder, that is, spherical, granular, or clumpy, has the smallest ratio of gaps in the powder mass that overlaps with the alcohol. When the fabric or nonwoven fabric finishes moving in the suspension, the powder mass covers the entire fabric or nonwoven fabric evenly with the alcohol. Furthermore, when the fabric or nonwoven fabric approaches the gap between the two work rolls, the alcohol evaporates, and the powder is precipitated on the fabric or nonwoven fabric in an overlapping manner, so that the fabric or nonwoven fabric is evenly covered with the powder mass. When this powder mass is compressed evenly, the small gaps in the powder mass at first are further reduced by the movement of the powder because the powder has a highly symmetrical shape. Next, when the hardness of the powder is low, the powder undergoes plastic deformation, and the plastically deformed powder comes into contact with adjacent powder and is joined by friction welding. Furthermore, all adjacent powders are joined by friction welding at all contact points. Also, overlapping powders are joined at all contact points. As a result, all voids present in the joined powder mass are confined inside the powder mass joined by friction welding, and no voids communicate with the outside world. Therefore, the coating has airtightness that blocks gas.Therefore, when a powder having excellent symmetry is used, the ratio of voids in the powder mass is the smallest after the alcohol evaporates, and when the powder mass is compressed, the small voids in the powder mass are further reduced by the movement of the powder, so that the thickness of the powder where the overlapping powders are joined can be thin. Therefore, the thickness of the suspension attached to the cloth or nonwoven fabric is thin. Furthermore, when the hardness of the powder is low, the powder is plastically deformed, and the plastically deformed powder fills the small voids and contacts the adjacent powder, and the powders are joined by friction welding. However, in the powder mass, the more symmetric the powder is, the less likely it is to plastically deform, and the harder the powder is, the more difficult it is to plastically deform. If excessive compressive stress is applied to such powder, the powder will be pulverized. Therefore, for powders having excellent symmetry, the gap between the two work rolls is changed according to the hardness of the powder, and the compressive stress applied to the powder is changed. As described above, the thickness of the suspension to be applied to the cloth or nonwoven fabric required to form an airtight coating that blocks gas is thin for powders having a spherical, granular, or agglomerated shape. Therefore, among the eight types of powder shapes described above, powders having a spherical, granular, or agglomerated shape are suitable for forming an airtight coating that blocks gas.

[0017] The powders described in paragraph 15, which are spherical, granular or agglomerated in shape, copper powder, tin powder, copper-tin alloy powder, tantalum powder, niobium powder, Fe-based alloy having a composition of Fe-17Cr-12Ni-Mo, Ni-based alloy having a composition of Ni-16Cr-16Mo-5Fe-4W, Co-based alloy powder having a composition of Co-29Cr-6Mo, alloy powder having a composition of Fe-49Co-2V, precipitation hardened martensitic stainless steel powder having a composition of SUS630, austenitic stainless steel powder having a composition of SUS316L, martensitic stainless steel powder having a composition of SUS420J2, or low-oxygen titanium powder, all of which are produced by a gas atomization method; Or, Copper powder or silver powder produced by water atomization method, Any one of these 15 types of powder is a powder having a spherical, granular, or agglomerated shape as described in paragraph 15.

[0018] In other words, the powder having a spherical, granular or agglomerated shape is manufactured by a manufacturing method specific to the powder. Here, the manufacturing method of the powder having a spherical, granular or agglomerated shape, the material of the manufactured powder, the specific properties of the powder, and the uses of the sheet will be described. The first manufacturing method is a gas atomization method in which compressed gas consisting of air, argon gas or nitrogen gas is sprayed onto a molten metal flowing down from a molten metal nozzle to produce powders made of various materials. The powder produced by the first gas atomization method is copper powder, which has a shape close to a sphere, and has excellent ductility and malleability. Therefore, it easily undergoes plastic deformation when subjected to compressive stress. Therefore, when a collection of overlapping copper powders is compressed, the copper powder moves and fills the gaps in the collection of copper powders, and further, the copper powder undergoes plastic deformation due to compressive stress, comes into contact with adjacent copper powders, and is joined by friction welding. Therefore, the number of overlapping copper powder sheets required to close the gaps inside the collection of copper powders joined by friction welding is relatively small. Furthermore, the larger the size of the copper powder, the larger the surface area of the copper powder, so the fewer the number of copper powder sheets that need to be overlapped. Therefore, the suspension that is attached to the entire cloth or nonwoven fabric can be thin. In addition, the compressive stress applied to the collection of copper powders is relatively small. In this way, the copper powder produced by the gas atomization method is suitable for powder that forms a coating that has airtightness to block gas. On the other hand, copper powder has both high electrical and thermal conductivity among metals, so sheets composed of copper powder particles bonded by friction welding and covered with a coating, or cut sheets, are used as lightweight conductive or thermally conductive sheets, or as substrates or electrodes for electrical circuits. The powder produced by the second gas atomization method is tin powder. Similar to copper powder, it has a shape close to spherical and is excellent in ductility and malleability, so it easily undergoes plastic deformation when subjected to compressive stress. Therefore, like the copper powder produced by the gas atomization method, tin powder is suitable for forming a film with airtightness that blocks gas. On the other hand, tin has high electrical conductivity and thermal conductivity, low density, and solderability, so the cut sheet is used as a lightweight substrate for electrical circuits. However, since the melting point of tin is as low as 232°C, it is not used for substrates of electrical circuits that become hot. The powder produced by the third gas atomization method is copper-tin alloy powder. It has a shape close to spherical and is excellent in ductility and malleability, so it easily undergoes plastic deformation when subjected to compressive stress. For example, there is copper-tin alloy powder with a composition of 90Cu-10Sn. Therefore, like the copper powder produced by the gas atomization method, copper-tin alloy powder is suitable for forming a film with airtightness that blocks gas. Note that the copper-tin alloy powder has a higher melting point than tin, and the cut sheet is used for substrates of electrical circuits with a heat-resistant temperature of 300°C or lower, lead frames of semiconductors, and heat sinks. The powder produced by the fourth gas atomization method is tantalum powder and niobium powder, which has a shape close to spherical. Therefore, when compressing the aggregates of overlapping tantalum powder or niobium powder, first, the tantalum powder or niobium powder moves to reduce the voids in the aggregates of tantalum powder or niobium powder. Next, adjacent powders in the powder aggregates are joined by friction pressure welding at all contact parts where the powders contact each other, and the aggregates of overlapping powders are joined by friction pressure welding. As a result, the whole of the fabric or non-woven fabric is covered with a film composed of the joined powder aggregates, and the voids are trapped inside the aggregates of tantalum powder or niobium powder joined by friction pressure welding. For this reason, the tantalum powder and niobium powder produced by the gas atomization method are suitable for powders that form a film having airtightness for blocking gas. Note that since the tantalum powder and niobium powder are harder than the above-described copper powder, tin powder, or copper-tin alloy powder, a large compressive stress is required to generate frictional heat at the contact parts between the tantalum powder or niobium powder. Therefore, the gap between the two work rolls is narrowed according to the hardness of the tantalum powder or niobium powder. On the other hand, since the tantalum powder is excellent in heat resistance and corrosion resistance, a sheet having a structure covered with a film formed by aggregates of tantalum powder joined by friction pressure welding, or a cut sheet, is used as a sheet used in a corrosive environment at a high temperature used in the chemical treatment process. Also, since the niobium powder is excellent in heat resistance and corrosion resistance like the tantalum powder, a sheet having a structure covered with a film formed by aggregates of niobium powder joined by friction pressure welding, or a cut sheet, is used as a sheet used in a corrosive environment at a high temperature used in the chemical treatment process. The powders produced by the fifth gas atomization method are the following three types of alloy powders, all of which have a shape close to spherical. Therefore, when compressing a collection of overlapping alloy powders, first, the alloy powders move to reduce the voids in the collection of alloy powders. Next, adjacent alloy powders in the collection of alloy powders are joined by friction pressure welding at all contact parts where they come into contact, and also, the collection of overlapping alloy powders is joined by friction pressure welding. As a result, the whole of the fabric or non-woven fabric is covered with a film composed of a collection of joined powders, and voids are trapped inside the collection of alloy powders joined by friction pressure welding. For this reason, the alloy powders produced by the gas atomization method are suitable for powders that form a film having airtightness to block gas. Since the alloy powders are harder than the above-mentioned copper powders, tin powders, or copper-tin alloy powders, a large compressive stress is required to generate frictional heat at the contact parts between the alloy powders. Therefore, the gap between the two work rolls is narrowed according to the hardness of the alloy powders. The Fe-based alloy composed of Fe-17Cr-12Ni-Mo has a composition close to that of SUS316L austenitic stainless steel and is excellent in corrosion resistance. Therefore, a sheet, a cut sheet, or a bent sheet having a structure covered with a film formed by a collection of Fe-based alloys composed of Fe-17Cr-12Ni-Mo joined by friction pressure welding is used for a sheet used in a liquid with strong corrosiveness. The Ni-based alloy composed of Ni-16Cr-16Mo-5Fe-4W is a Ni-based alloy corresponding to Hastelloy C276 and is excellent in corrosion resistance. Therefore, a sheet, a cut sheet, or a bent sheet having a structure covered with a film formed by a collection of Ni-based alloys composed of Ni-16Cr-16Mo-5Fe-4W joined by friction pressure welding is used for a sheet used in a liquid with strong corrosiveness. The Co-based alloy powder composed of Co-29Cr-6Mo is excellent in corrosion resistance and has high fatigue strength. Therefore, a sheet, a cut sheet, or a bent sheet having a structure covered with a film formed by a collection of Co-based alloy powders composed of Co-29Cr-6Mo joined by friction pressure welding is used for a sheet that is constantly loaded in a liquid with strong corrosiveness. The powder produced by the sixth gas atomization method is an alloy powder composed of Fe-49Co-2V, called a Permendur alloy powder, and its shape is close to spherical. Therefore, when compressing a collection of overlapping alloy powders, first, the alloy powders move to reduce the voids in the collection of alloy powders. Next, adjacent alloy powders in the collection of alloy powders are joined by friction pressure welding at all contact parts where they contact each other, and also, the collection of overlapping alloy powders is joined by friction pressure welding. As a result, the whole of the fabric or non-woven fabric is covered with a film composed of the joined collection of alloy powders, and the voids are trapped inside the collection of alloy powders joined by friction pressure welding. Therefore, the alloy powder composed of Fe-49Co-2V produced by the gas atomization method is suitable for powders that form a film with airtightness to block gas. This alloy powder has a large magnetic flux density B25 of 2.3 tesla, a coercive force of 46 A / m, and a maximum magnetic permeability of 10,000. On the other hand, the Rockwell hardness HRB is as low as 40 (equivalent to a Vickers hardness HV of 80), and it is easy to process. Therefore, the cut sheet or the bent sheet is used for the iron core of a motor or a generator with high power. The powder produced by the seventh gas atomization method is the following three types of stainless steel powders, all of which have a shape close to spherical. Therefore, when compressing a collection of overlapping stainless steel powders, first, the stainless steel powders move to reduce the voids in the collection of stainless steel powders. Next, adjacent powders in the collection of stainless steel powders are joined by friction pressure welding at all contact parts where they contact each other, and also, the collection of overlapping stainless steel powders is joined by friction pressure welding. As a result, the whole of the fabric or non-woven fabric is covered with a film composed of the joined collection of stainless steel powders, and the voids are trapped inside the collection of stainless steel powders joined by friction pressure welding. Therefore, similar to the above-mentioned alloy powder, it is suitable for powders that form a film with airtightness to block gas. Since the stainless steel powder has a high hardness, the compression stress required to generate frictional heat at the contact parts between the stainless steel powders is large. Therefore, the gap between the two work rolls is narrowed according to the hardness of the stainless steel powder. Precipitation hardening martensitic stainless steel powder composed of the composition of SUS630 has heat resistance and corrosion resistance equivalent to those of SUS304. Therefore, a sheet composed of a structure covered with a film formed by an aggregation of precipitation hardening martensitic stainless steel powder, or a cut sheet, or a bent sheet is used for a sheet used in a high-temperature environment with strong corrosiveness. Austenitic stainless steel powder composed of the composition of SUS316L is excellent in ductility and toughness, and has high corrosion resistance and high formability. Therefore, a sheet composed of a structure covered with a film formed by an aggregation of austenitic stainless steel powder composed of the composition of SUS316L, or a cut sheet, or a bent sheet is used as a sheet with a complex shape in an environment with strong corrosiveness because it is thin and excellent in workability. Martensitic stainless steel powder composed of the composition of SUS420J2 is a high-strength stainless steel. Therefore, a sheet composed of a structure covered with a film formed by an aggregation of martensitic stainless steel powder composed of the composition of SUS420J2, or a cut sheet, or a bent sheet is used for a sheet to which a large load is constantly applied in an environment with strong corrosiveness. In addition, since the martensitic stainless steel powder composed of the composition of SUS420J2 has a high hardness, after the sheet is manufactured, a annealing treatment is performed. This facilitates the processing of the bent sheet. The powder produced by the eighth gas atomization method is low-oxygen titanium powder, which has a shape close to spherical. Therefore, when compressing a collection of overlapping low-oxygen titanium powder, first, the low-oxygen titanium powder moves to reduce the voids in the collection of low-oxygen titanium powder. Next, adjacent powders in the collection of low-oxygen titanium powder are joined by friction pressure welding at all contact parts where they contact. Further, the collections of overlapping low-oxygen titanium powder are joined by friction pressure welding. Since the low-oxygen titanium powder has high hardness, the compression stress required to generate frictional heat at the contact parts between the low-oxygen titanium powders is large. Therefore, according to the hardness of the low-oxygen titanium powder, the gap between the two work rolls is narrowed. As a result, the entire fabric or non-woven fabric is covered with a coating composed of a collection of joined low-oxygen titanium powder, and the voids are trapped inside the collection of low-oxygen titanium powder joined by friction pressure welding. For this reason, the low-oxygen titanium powder is suitable for a powder that forms a coating having airtightness to block gas. Since the low-oxygen titanium powder has excellent corrosion resistance and is suitable for manufacturing high-strength parts, a sheet or a cut sheet having a structure covered with a coating formed by a collection of low-oxygen titanium powder is used as a sheet in the aerospace and medical fields. The powders produced by the first water atomization method are copper powder and silver powder, both of which have a granular shape and are powders with excellent symmetry following the above-mentioned spherical shape. Also, both the copper powder and the silver powder have excellent ductility and malleability and easily undergo plastic deformation when subjected to compressive stress. Therefore, similar to the copper powder produced by the gas atomization method, it is suitable for a powder that forms a coating having airtightness to block gas. Since copper and silver have high electrical conductivity and thermal conductivity among metals, a sheet, a cut sheet, or a bent sheet having a structure covered with a coating formed by a collection of copper powder or silver powder joined by friction pressure welding is used as a lightweight conductive sheet, a lightweight heat conduction sheet, or a lightweight heat sink. By the way, the third method for producing powder is a reduction method in which ore made of metal oxide is used as a starting material, and the ore is reduced with a gas with strong reducing properties at high temperature to produce metal powder, and iron powder, copper powder, nickel powder, cobalt powder, tungsten powder, and molybdenum powder are produced. However, since the powder has a sponge-like shape and is porous, many voids are formed in the collection of overlapping metal powder particles, and further, many voids remain in the coating formed by compressing the collection of overlapping metal powder particles, making it unsuitable for producing airtight sheets. Furthermore, a fourth powder manufacturing method involves dissolving scrap in a solvent and reducing the product to produce metal powder. However, as with the ore reduction method described above, the metal powder is porous, and many voids are formed in the overlapping metal powder particles. Furthermore, voids remain in the coating formed by compressing the overlapping metal powder particles, making the method unsuitable for manufacturing an airtight sheet. A fifth method for producing powder is a method for producing metal powder by electrolysis, which produces copper powder, silver powder, and iron powder. However, since the metal powder is sponge-like or dendritic, many voids are formed in the overlapping metal powder particles, and further, voids remain in the coating formed by compressing the overlapping metal powder particles, making the method unsuitable for producing an airtight sheet. As described above, powders having a spherical, granular, or agglomerated shape are produced by gas atomization and water atomization to produce powders of 15 types of metals or alloys. Powders made of metals or alloys have inherent properties according to the material in addition to electrical conductivity. As a result, the sheet has the inherent properties of the powder in addition to the electrical conductivity, non-combustibility, corrosion resistance, and heat resistance described in paragraph 12. Therefore, the sheet can be used for various purposes based on the inherent properties of the powder.

[0019] A method for continuously producing a sheet having a structure in which a woven fabric or nonwoven fabric is entirely covered with a coating formed by an aggregate of powder particles bonded by friction welding as described in paragraph 11, comprising the steps of: The powder described in paragraph 11 has a sponge-like shape but is not porous, and is a powder that undergoes plastic deformation when compressed in the third step described in paragraph 11. A method of using this powder as the powder described in paragraph 11 and continuously performing all the processes of the three steps described in paragraph 11 in sequence is a manufacturing method for continuously manufacturing a sheet having a structure in which a film formed by the powder joined by friction welding described in paragraph 11 covers the entire fabric or non-woven fabric.

[0020] The film formed by the aggregation of powders joined by friction welding in the present invention is a film in which the aggregations of powders overlap and are joined, and the thickness of the joined aggregation of powders is thinner than 0.25 mm. As a result, the sheet can be cut, which is the second property described in paragraph 12. On the other hand, in order for the film in which the aggregations of powders overlap and are joined to have airtightness that blocks gas, which is the fourth property described in paragraph 12, the shape of the powder used is restricted. That is, by the treatment of the second step described in paragraph 11, the suspension adheres evenly to the entire fabric or non-woven fabric. Further, in the third step described in paragraph 11, after vaporizing the alcohol from the suspension, the aggregations of powders deposited overlapping on the fabric or non-woven fabric are evenly compressed. At this time, for powders with low hardness, the powders undergo plastic deformation, the plastically deformed powders fill the adjacent voids, and the voids shrink. Also, all the contact portions where adjacent powders contact each other are joined by friction welding. Further, the overlapping aggregations of powders are joined by friction welding. Therefore, if all the voids are enclosed inside the joined aggregation of powders, the film composed of the joined aggregation of powders has no voids communicating with the outside and has airtightness that blocks gas. By the way, as described in paragraph 16, there are eight types of powder shapes. Among these eight types of powder, there is a powder having a sponge-like shape. If the powder having a sponge-like shape has, first, non-porous and, second, the property of undergoing plastic deformation when the powder is compressed in the third step described in paragraph 11, the film composed of the aggregation of powders having a sponge-like shape has airtightness that blocks gas. That is, in the second step described in paragraph 11, when the fabric or nonwoven fabric immersed in the suspension moves horizontally in the suspension at a low speed from the second roller to the penultimate roller, the powder constituting the suspension adsorbed on the surface of the fabric or nonwoven fabric is loaded because the powder is small (micron size) and lightweight. This load causes the phenomenon of the sponge-shaped powder particles overlapping each other through the alcohol. At this time, since the powder particles vary in size, when the powder is adsorbed on the fabric or nonwoven fabric with the alcohol, the powder particles overlap each other through the alcohol to fill the gaps, and the accumulation density of the powder particles increases. However, compared to the spherical, granular, or clumpy powder described in paragraph 16, the sponge-shaped powder is less symmetrical, so the powder particles overlapping each other through the alcohol have many voids where no powder is present, and the voids are filled with alcohol. Therefore, many voids remain in the coating formed by compressing the powder mass, and voids that communicate with each other are formed in the coating, so that the coating does not have the airtightness to block gas. On the other hand, when a spongy powder with a relatively low hardness is subjected to compressive stress, it undergoes plastic deformation in a direction perpendicular to the compression direction. In addition, spongy powder is prone to plastic deformation because it is poorly symmetrical. For this reason, after evaporating the alcohol, a compressive stress according to the hardness of the powder is evenly applied to the overlapping spongy powder collection, and the powder is plastically deformed in a direction perpendicular to the compression direction. If there are voids in the adjacent powders, the plastically deformed powder will enter the voids and reduce the voids. In other words, regardless of the size of the voids, if there are voids in the adjacent powders, the plastically deformed powder will reduce the voids. However, not all voids are filled by the plastic deformation of the powder. For this reason, it is necessary to bond the overlapping precipitated powders together, and confine all voids inside the bonded powder collection by a bonding layer consisting of the bonded powder collection. Therefore, it is necessary to use alcohol with a relatively high viscosity and increase the thickness of the layer of overlapping powders. The larger the spongy powder, the larger the surface area of the powder, so the number of overlapping powder sheets can be relatively small. On the other hand, the plastically deformed powder forms a joint with the adjacent powder as a joint close to a surface, and the powders are joined by friction welding at this joint. The joint between the powders has a larger contact area than the contact between the spherical, granular, or clumped powders described in paragraph 16. Therefore, the bonding strength between the powders in the spongy powder group is greater than the bonding strength between the powders in the spherical, granular, or clumped powder group described in paragraph 16. Furthermore, since the spongy powder is not porous, by using alcohol with a relatively high viscosity to thicken the layer of overlapping powder, the bonding layer consisting of the overlapping and bonded powder group can confine all voids inside the bonded powder group. In other words, if the powder is porous, voids will remain in the areas where porosity is formed, even if the layer of overlapping powder is thickened. On the other hand, the smaller the size of the non-porous sponge-like powder, the smaller the surface area of the powder. Therefore, when using a powder with a small size of non-porous sponge-like powder, an alcohol with a relatively high viscosity is used to increase the thickness of the overlapping powder layer. Through these treatments, the film formed by the aggregation of powders in which non-porous sponge-like powders are joined by frictional pressure bonding has no voids communicating with the outside. As a result, the film has airtightness. As described above, a powder that has a sponge-like shape but is not porous and that plastically deforms when compressed in the third step described in paragraph 11 plastically deforms in a direction perpendicular to the compression direction, and the plastically deformed powder enters the voids between adjacent powders, reducing the voids where there is no powder. Further, all the voids are confined inside the aggregate of joined powders by the joined layer composed of the aggregate of overlapping and joined powders. Thereby, the film formed by the aggregation of powders has airtightness to block gas. Therefore, a powder that has a sponge-like shape but is not porous and that plastically deforms when compressed in the third step described in paragraph 11 is suitable for the shape of a powder that forms an airtight film.

[0021] The powder that has a sponge-like shape but is not porous and that plastically deforms when compressed in the third step described in paragraph 19 is iron powder or bronze powder produced by the water atomization method, and either one of these two types of powders is a powder that has a sponge-like shape but is not porous and that plastically deforms when compressed in the third step described in paragraph 19.

[0022] That is, a powder that has a sponge-like shape but is not porous and that plastically deforms when compressed in the third step described in paragraph 11 is produced by a specific manufacturing method of the powder. Here, a method for manufacturing a powder that has a sponge-like shape but is not porous and that plastically deforms when compressed in the third step described in paragraph 11, the material of the produced powder, the specific properties of the powder, and the use of the sheet are described. The first powder is the iron powder produced by the water atomization method described in paragraph 18. The iron powder produced by the water atomization method has a spongy shape but is not porous. On the other hand, the metals with the highest ductility are silver, iron, nickel, copper, aluminum, zinc, and tin in that order. Also, the metals with the highest malleability are silver, copper, aluminum, tin, zinc, iron, and nickel in that order. Therefore, when the iron powder produced by the water atomization method is compressed, the iron powder is plastically deformed in a direction perpendicular to the compression direction. As a result, the voids formed in the collection of iron powder particles are reduced by the plastically deformed iron powder. However, it is not possible to fill all the voids in the collection of iron powder particles with the plastically deformed iron powder. Therefore, the number of overlapping iron powder particles is increased, and the number of overlapping and bonded iron powder particles is increased. As a result, all the voids in the bonded collection of iron powder particles are enclosed inside the collection of iron powder particles. In other words, metal powder with excellent ductility and malleability does not necessarily have to be spherical, granular, or clump-shaped powder. Metal powder with poor symmetry is more susceptible to plastic deformation, so in metal powder with excellent ductility and malleability, all voids in the bonded metal powder mass are trapped inside the metal powder mass. Also, the larger the metal powder, the larger the surface area of the metal powder, so fewer sheets of metal powder need to be stacked. On the other hand, iron is the only soft magnetic material made of ferromagnetic metals that has a constant magnetic permeability in an alternating magnetic field. For this reason, a sheet made of a composition covered with a mass of iron powder bonded by friction welding, or a cut sheet or a folded sheet, can effectively act as a shielding sheet to shield magnetism. The second powder includes bronze powder made of an alloy of copper and tin produced by the water atomization method, for example, bronze powder having a composition of 90Cu-10Sn. The bronze powder produced by the water atomization method has a spongy shape but is not porous. On the other hand, since the bronze powder has excellent ductility and malleability, when the bronze powder is compressed, the bronze powder plastically deforms in a direction perpendicular to the compression direction. As a result, the voids formed in the aggregation of the bronze powder are reduced by the plastically deformed bronze powder. However, not all the voids in the aggregation of the bronze powder can be filled with the plastically deformed bronze powder. Therefore, the number of overlapping bronze powders is increased, and the number of joined bronze powders is increased. As a result, all the voids in the aggregation of the joined bronze powders are confined inside the aggregation of the bronze powders. Incidentally, since the bronze powder made of an alloy of copper and tin has a bactericidal action, a sheet having a structure covered with an aggregation of bronze powders joined by friction pressure welding is used as a sheet that people touch. Also, since the bronze powder emits a shiny red copper color to a golden color depending on the tin content, it is used as a lightweight sheet that emits a red copper color to a golden color. As described above, there are iron powder and bronze powder produced by the water atomization method for powders that have a spongy shape but are not porous and plastically deform under compressive stress. These powders have unique properties according to the material in addition to electrical conductivity. Thus, a sheet having a structure in which a fabric or non-woven fabric is covered with a film formed by an aggregation of powders joined by friction pressure welding has the properties specific to the powders in addition to the electrical conductivity, incombustibility, corrosion resistance, and heat resistance described in paragraph 12. As a result, the sheet can be used for various applications based on the properties specific to the powders.

[0023] A manufacturing method for continuously manufacturing a sheet having a structure in which the entire fabric or non-woven fabric is covered with a film formed by an aggregation of powders joined by friction pressure welding described in paragraph 11 is The powder described in paragraph 11 is teardrop-shaped or spindle-shaped and undergoes plastic deformation when compressed in the third step described in paragraph 11, and a method of using this powder as the powder described in paragraph 11 and carrying out all of the three steps described in paragraph 11 in sequence is a method for continuously producing a sheet having a structure in which a woven fabric or nonwoven fabric is entirely covered with a coating formed by an aggregate of powder particles bonded by friction welding as described in paragraph 11.

[0024] That is, in the second step described in paragraph 11, when the fabric or nonwoven fabric immersed in the suspension moves horizontally in the suspension at a low speed from the second roller to the penultimate roller, the powder constituting the suspension adsorbed on the surface of the fabric or nonwoven fabric is loaded because the powder is micron-sized and extremely light. This load causes teardrop-shaped or spindle-shaped powder clusters to gradually overlap over the entire fabric or nonwoven fabric through the alcohol. At this time, since the powder varies in size and shape, the powder clusters overlap through the alcohol to fill the gaps, and the accumulation density of the powder clusters gradually increases. In this way, the entire fabric or nonwoven fabric is covered with the powder clusters overlapping through the alcohol. However, compared to the spherical, granular, or lump-shaped powders described in paragraph 16, teardrop- or spindle-shaped powders are less symmetrical, and so the powder particles overlapping each other through the alcohol have many voids where no powder is present, which are filled with alcohol. Due to the presence of these voids, the coating formed by compressing the powder particles has many voids, and the coating does not have the airtightness to block gas. On the other hand, when a compressive stress is applied to teardrop-shaped or spindle-shaped powders, which have a relatively low hardness, they undergo plastic deformation in a direction perpendicular to the compression direction. Therefore, when the entire overlapping powder mass is compressed evenly after the alcohol is evaporated, the powder undergoes plastic deformation in a direction perpendicular to the compression direction, and the plastically deformed powder enters the voids of adjacent powders, and the voids where no powder is present are reduced by the plastically deformed powder. In other words, regardless of the size of the voids where no powder is present, if there are voids in adjacent powders, the powder undergoes plastic deformation, and the plastically deformed powder fills the adjacent voids, reducing the voids. However, not all voids are filled by the plastic deformation of the powder. For this reason, it is necessary to join the piled-up precipitated powders together, and confine all voids inside the joined powder mass by a joining layer consisting of the overlapping and joined powder mass. In other words, metal powders with relatively low hardness do not necessarily have to be spherical, granular or agglomerated powders, and since less symmetrical metal powders are more likely to undergo plastic deformation, all voids in the joined metal powder mass can be contained within the metal powder mass. Also, the larger the metal powder, the greater the surface area of the metal powder, so fewer metal powder sheets need to be stacked. Furthermore, teardrop-shaped or spindle-shaped powders are not porous, so there are no voids in the powder mass where the powders are joined together. In contrast, if the powder is porous, voids remain in the areas where the porosity is formed, even if the thickness of the overlapping powder layers is increased. Also, the plastically deformed powder forms a joint with the adjacent powder as a joint close to the surface, and the powders are joined together by friction welding at this joint. The joint between the powders has a larger contact area than the contact between the spherical, granular or agglomerated powders described in paragraph 16. Therefore, the adhesive strength between powder particles in a teardrop- or spindle-shaped mass of powder is greater than the adhesive strength between powder particles in a spherical, granular, or agglomerated mass of powder as described in paragraph 16. On the other hand, the smaller the size of the non-porous teardrop-shaped or spindle-shaped powder, the smaller the surface area of the powder. Therefore, when using a powder with a small size of non-porous teardrop-shaped or spindle-shaped powder, an alcohol with a relatively high viscosity is used to increase the number of overlapping powders. Through these treatments, there are no voids in the film formed by the aggregation of powders joined by friction and pressure contact between the stacked and deposited powders, so there are no voids communicating with the outside world. Therefore, the film has airtightness that blocks gas. As described above, a powder having a teardrop shape or a spindle shape and being plastically deformed when compressed in the third step described in paragraph 11 causes the powder to be plastically deformed in a direction perpendicular to the compression direction and enter the voids between adjacent powders, reducing the voids where there is no powder. Further, the overlapping powders are joined by friction and pressure contact. As a result, all voids are trapped inside the aggregate of the joined powders. Therefore, there are no voids communicating with the outside world in the film formed by the aggregate of powders joined by friction and pressure contact. As a result, the film has airtightness that blocks gas. Therefore, a powder having a teardrop shape or a spindle shape and being plastically deformed when compressed in the third step described in paragraph 11 is suitable for the shape of a powder that forms an airtight film.

[0025] The powder having the teardrop shape or the spindle shape described in paragraph 23 and being plastically deformed when compressed in the third step described in paragraph 11 is aluminum powder produced by the gas atomization method, nickel powder produced by the water atomization method, Fe-3Si alloy powder, 47Ni-Fe alloy powder, 78Ni-4Mo-Fe alloy powder, or brass powder, any one of these six types of powders is a powder having the teardrop shape or the spindle shape described in paragraph 23 and being plastically deformed when compressed in the third step described in paragraph 11.

[0026] That is, the powder having a teardrop or spindle shape and plastically deforming when compressed in the third step described in paragraph 11 is produced by a specific manufacturing method of the powder. Here, a method for producing a powder having a teardrop or spindle shape and plastically deforming when compressed in the third step described in paragraph 11, the material of the produced powder, the specific properties of the powder, and the use of the sheet are described. Among the first powders, there is aluminum powder produced by the gas atomization method described in paragraph 18. The aluminum powder has a teardrop shape and excellent malleability and ductility. Therefore, when the aluminum powder produced by the gas atomization method is compressed, the aluminum powder plastically deforms in a direction perpendicular to the compression direction. As a result, the voids formed in the aggregate of the aluminum powder are reduced by the plastically deformed aluminum. Further, the aluminum powder particles deposited by stacking are joined together, and all the voids are confined inside the aggregate of the joined aluminum powder particles by a joining layer composed of the aggregate of the overlapped and joined aluminum powder particles. Note that, like the copper powder, since the aluminum powder has high conductivity and high thermal conductivity, a sheet having a structure covered with an aggregate of aluminum powder joined by friction pressure welding, or a cut sheet, is used as a lightweight conductive sheet, a lightweight heat sink, a substrate or an electrode of an electric circuit. The second powder includes nickel powder produced by the water atomization method described in Paragraph 18. The nickel powder has a shape close to a teardrop shape with variations in shape. Also, as described above, the nickel powder has excellent ductility and malleability. Therefore, when the nickel powder is compressed, the nickel powder plastically deforms in a direction perpendicular to the compression direction. As a result, the plastically deformed nickel enters the voids formed in the aggregation of nickel powder, and the voids are reduced. Further, the nickel powder deposits and overlaps, and the joined layers composed of the aggregation of the overlapped and joined nickel powder bodies confine all the voids inside the aggregation of the joined nickel powder bodies. Note that nickel has high corrosion resistance against strong acids and strong alkalis and excellent workability. Therefore, a sheet or a cut sheet having a structure covered with an aggregation of nickel powder joined by friction pressure welding is used as a lightweight corrosion-resistant sheet in a chemical manufacturing plant or the like. Also, since nickel has excellent heat resistance, a sheet having a structure covered with an aggregation of nickel powder joined by friction pressure welding is used as a lightweight sheet for an engine. The third powder includes Fe-3Si alloy powder (3% silicon iron) produced by the water atomization method. This alloy powder is a powder having a teardrop shape or a spindle shape. Also, since the Vickers hardness of the alloy powder is as high as around 200 HV, when the alloy powder is compressed, the amount of plastic deformation of the alloy powder in a direction perpendicular to the compression direction is small. Therefore, the amount of the plastically deformed alloy powder entering the voids formed in the aggregation of the alloy powder and the reduction of the voids are small. For this reason, alcohol having a relatively high viscosity is used, and when the alcohol vaporizes from the suspension, the number of deposited alloy powder sheets overlapping each other is increased. Further, the alloy powder deposits and overlaps, and the joined layers composed of the aggregation of the overlapped and joined alloy powder bodies confine all the voids inside the aggregation of the joined alloy powder bodies. Note that the magnetic permeability of the Fe-3Si alloy powder does not change depending on the direction. Therefore, it is used as a soft magnetic steel sheet having a complex shape such as an armature of a motor. Therefore, a sheet having a structure covered with an aggregation of Fe-3Si alloy powder joined by friction pressure welding can be cut into a thin thickness and used in the shape of an armature. Among the fourth powder, there is 47Ni-Fe alloy powder (equivalent to PB permalloy) produced by the water atomization method. The shape of this powder is teardrop-shaped or spindle-shaped. Also, since the Vickers hardness of the alloy powder is as low as around 100 HV, when the alloy powder is compressed, the alloy powder plastically deforms in a direction perpendicular to the compression direction. As a result, the plastically deformed alloy powder enters the voids formed in the aggregation of the alloy powder, and the voids are reduced. Furthermore, the alloy powder aggregates deposited by stacking are joined together, and all the voids are confined inside the aggregation of the joined alloy powder by a joining layer composed of the aggregation of the alloy powder joined and overlapped. Note that the 47Ni-Fe alloy powder has a large initial permeability of 5,000, a large maximum permeability of 50,000, and a large maximum magnetic flux density of 1.55 tesla. On the other hand, the coercive force is as small as 12 A / m. For this reason, a sheet composed of a structure covered with an aggregation of 47Ni-Fe alloy powder joined by friction pressure welding, or a cut sheet, is used for a magnetic shielding sheet, a sheet for a magnetic sensor, a core used for various inductors, a shielding case for noise cutting of a measuring instrument, and a control device for an inverter motor. Among the fifth powders, there is 78Ni-4Mo-Fe alloy powder (equivalent to PC permalloy) produced by the water atomization method. The shape of this powder is in the form of a teardrop or spindle. Also, since the Vickers hardness of the alloy powder is as low as around 100 HV, when the alloy powder is compressed, the alloy powder plastically deforms in a direction perpendicular to the compression direction. As a result, the plastically deformed alloy enters the voids formed in the collection of alloy powder, and the voids are reduced. Further, the alloy powders deposited by stacking the alloy powders are joined together, and all the voids are confined inside the collection of joined alloy powders by a joining layer composed of the collection of overlapping and joined alloy powders. Incidentally, the 78Ni-4Mo-Fe alloy powder has an extremely large initial permeability of 60,000, an extremely large maximum permeability of 180,000, and a maximum magnetic flux density of 0.72 tesla. On the other hand, the coercive force is extremely small at 0.8 A / m. Therefore, similar to the 47Ni-Fe alloy powder, a sheet composed of a structure covered with a collection of 78Ni-4Mo-Fe alloy powder joined by friction pressure welding, or a cut sheet, is used for a magnetic shielding sheet, a sheet for a magnetic sensor, a core used for various inductors, a shielding case for noise cutting of measuring instruments, and a control device for an inverter motor. Among the sixth powders, there is brass powder of an alloy composed of copper and zinc produced by the water atomization method, for example, brass powder having a composition of 60Cu-40Sn. The shape of this powder is close to a teardrop shape with variations in shape. Also, since the brass powder has excellent ductility and malleability, when the brass powder is compressed, the brass powder plastically deforms in a direction perpendicular to the compression direction. As a result, the plastically deformed brass powder enters the voids formed in the collection of brass powder, and the voids are reduced. Further, the brass powders deposited by stacking the brass powders are joined together, and all the voids are confined inside the collection of joined brass powders by a joining layer composed of the collection of overlapping and joined brass powders. Incidentally, since the brass powder has a beautiful color due to its golden shiny appearance, a sheet composed of a structure covered with a collection of brass powder joined by friction pressure welding, or a cut sheet, is used as a lightweight sheet that shines in a golden color. Also, since brass has excellent workability, it is used as a sheet-like part used in precision machinery such as banknote printing machines and various scientific instruments. As described above, there are powders made of teardrop or spindle shapes, and powders that plastically deform when compressed, which are powders made of metals or alloys of various materials. These powders made of metals or alloys have, in addition to conductivity, unique properties according to the material as described above. As a result, a sheet having a configuration in which a film formed by a collection of powders joined by friction pressure welding covers a fabric or non-woven fabric has, in addition to the conductivity, incombustibility, corrosion resistance, and heat resistance described in paragraph 12, the properties inherent to the powders. Therefore, the sheet can be used for various applications.

[0027] A manufacturing method for continuously manufacturing a sheet having a configuration in which a film formed by a collection of powders joined by friction pressure welding described in paragraph 11 covers the entire fabric or non-woven fabric is The powder described in paragraph 11 is a powder having a plate-like, flake-like, or scaly shape with a large aspect ratio of the powder. A method of using the powder as the powder described in paragraph 11 and sequentially and continuously performing all the processes of the three processes described in paragraph 11 is a manufacturing method for continuously manufacturing a sheet having a configuration in which a film formed by a collection of powders joined by friction pressure welding described in paragraph 11 covers the entire fabric or non-woven fabric.

[0028] The film formed by the aggregation of powders joined by friction welding in the present invention is a film formed by the aggregation of powders overlapping and joining, and the thickness of the aggregated joined powders is thinner than 0.25 mm. As a result, the sheet can be cut, which is the second property described in paragraph 12. On the other hand, in order for the film formed by the aggregation of powders overlapping and joining to have airtightness that blocks gas, which is the fourth property described in paragraph 12, the shape of the powders used is restricted. That is, by the treatment of the third step described in paragraph 11, the suspension adheres evenly to the entire fabric or non-woven fabric. Further, after vaporizing the alcohol from the suspension, the aggregation of powders deposited overlapping on the fabric or non-woven fabric is compressed. At this time, powders with low hardness undergo plastic deformation, and the plastically deformed powders fill the adjacent voids, reducing the voids. Also, all contact portions where adjacent powders contact each other are joined by friction welding. Further, the aggregated overlapping powders are joined by friction welding. Therefore, if all the voids are enclosed inside the aggregated joined powders, the film composed of the aggregated joined powders has no voids communicating with the outside and has airtightness that blocks gas. Incidentally, as described in paragraph 16, the powder made of any of metals, alloys, metal oxides or nitrides with a size in the micron range has eight types of shapes. On the other hand, in the first step described in paragraph 11, when creating a suspension in which alcohol is stirred and the powder is dispersed, plate-shaped, flaky or scaly powders with a large aspect ratio move in alcohol with the plane facing up because this places the least load on the powder. For this reason, an aggregate of powders with the plane facing up forms a suspension dispersed in alcohol. Furthermore, in the second step described in paragraph 11, the fabric or non-woven fabric moves horizontally in the suspension at a slow speed from the second roller to the second last roller. However, since the powder constituting the suspension adsorbed on the surface of the fabric or non-woven fabric is as small as the micron size and lightweight, a load is applied to the powder. Due to this load, the phenomenon in which the powders with the plane facing up overlap and adsorb to the fabric or non-woven fabric through alcohol progresses, and the entire fabric or non-woven fabric is covered with an aggregate of powders whose planes overlap through alcohol. Furthermore, in the third step described in paragraph 11, when the alcohol vaporizes, the aggregates of powders overlap with each other in planes, and furthermore, a compressive stress is applied to the aggregates of powders whose planes overlap. All the contact parts where the planes overlap are joined by friction welding, and a film composed of an aggregate of powders with the planes joined is formed. Also, since the overlapping powders are joined in planes, even if the number of overlapping powders is smaller compared to powders of other shapes, all the voids present in the aggregate of joined powders are confined inside the aggregate of powders, and a film is formed with no voids communicating with the outside. For this reason, the film has airtightness. However, when the size of the powder is small, since the surface area of the powder is small, it is necessary to increase the number of overlapping powders in order to confine all the voids present in the aggregate of joined powders inside the aggregate of powders. That is, there are powders with an average particle size of 10 μm or less in plate-shaped, flaky or scaly powders with a large aspect ratio. In plate-shaped, flaky or scaly powders with a large aspect ratio, when the average particle size of the powder differs by 5 times, the average surface area of the powder differs by nearly 25 times.Therefore, the smaller the average surface area of the powder, the more necessary it is to increase the number of overlapping powders. In addition, for a collection of powders with their planes joined together, since the joining area where the planes join is large, the joining strength between the powders is greater than that of a collection of powders with other shapes. For this reason, the mechanical strength of the sheet covered with the film is greater than that of the sheet covered with the film formed by a collection of powders with other shapes. In addition, in the case of plate-like, flake-like, or scaly powders with a relatively low hardness and a large aspect ratio, the powders also overlap with their planes facing each other. On the other hand, because the hardness of the powder is relatively low, even if the compressive stress applied to the collection of powders is small, the powder undergoes plastic deformation, the gap between the powders overlapping with their planes narrows, and furthermore, the contact area between the powders increases, and the powders firmly join with their planes facing each other. In contrast, in the case of plate-like, flake-like, or scaly powders with a relatively high hardness and a large aspect ratio, when compressive stress is applied to the collection of powders, the gap between the powders overlapping with their planes narrows, but since the powder does not undergo plastic deformation, voids remain in the gap between the powders. For this reason, by applying a relatively large compressive stress to the collection of powders, the voids narrow, and a portion where the powders overlapping with their flat surfaces contact each other is formed, and by this portion, the planes join by friction pressure welding. Therefore, compared with the joining force between powders with a relatively low hardness, the joining force between the powders is inferior. As described above, powders having a large aspect ratio and being plate-like, flake-like, or scaly in shape overlap with their planes facing up over the entire fabric or non-woven fabric through alcohol. When the alcohol vaporizes, a collection of powders with their planes overlapping with their planes facing up covers the entire fabric or non-woven fabric. After that, when the collection of powders is evenly compressed, all the contact parts between the planes are joined by friction pressure welding, and a film with airtightness is formed. Therefore, powders having a large aspect ratio and being plate-like, flake-like, or scaly in shape are suitable as the shape of powders for forming a film with airtightness.

[0029] The powders having a large aspect ratio and being plate-like, flake-like, or scaly in shape described in paragraph 27 are Flake powder of soft metal composed of gold powder, silver powder, copper powder, tin powder, zinc powder, or aluminum powder obtained by crushing soft metal powder with a stamp mill, or Flat powder of soft magnetic alloy composed of silicon steel powder with a silicon addition of less than 10% obtained by attriting atomized soft magnetic powder or reduced soft magnetic powder with a media agitation type mill, permalloy powder with a nickel addition of 50% or less, sendust powder with an aluminum addition of at least 1 / 2 of the silicon addition, or electromagnetic stainless steel powder with an aluminum addition of less than 2%, or Flat powder of metal oxide composed of alumina powder produced by hydrothermal synthesis of aluminum hydroxide, mica powder produced by finely pulverizing muscovite, glass flake powder produced by crushing hollow-expanded molten glass, or hematite powder precipitated by hydrotreating yellow iron oxide in an alkaline aqueous solution, or Hexagonal boron nitride powder produced by crushing massive boron nitride, Any one of these 15 types of powders is a powder having a large aspect ratio of the powder described in paragraph 27 and having a plate-like, flake-like, or scaly shape.

[0030] That is, a powder having a large aspect ratio of the powder and having a plate-like, flake-like, or scaly shape is produced by a specific manufacturing method of the powder. Here, a method for producing a powder having a large aspect ratio of the powder and having a plate-like, flake-like, or scaly shape, the material of the produced powder, the specific properties of the powder, and the use of the sheet are described. The first powder includes flake powder of soft metal obtained by crushing soft metal powder with a stamp mill. Using a stamp mill corresponding to a crusher, a number of metal pestles are used to strike a collection of powder made of soft metal such as gold, silver, copper, tin, zinc or aluminum, and the soft metal powder is extended into thin flakes. As a result, flake powder of soft metal with a large aspect ratio, which is the ratio of the major axis to the thickness of the powder, and having a smooth surface close to a plane is obtained. Therefore, even for expensive flake powder of gold or silver, a small amount of flake powder can form a sheet emitting the color of a metal composed of a film in which flat surfaces are joined. In many cases, the metal powder as a raw material has a high purity of the metal, and lead-free electrolytic metal powder is used. On the other hand, in the production of aluminum flake powder, when granular powder or cut pieces of foil by the atomization method are struck with a stamp mill, aluminum powder is likely to burn and also likely to adhere. Therefore, stearic acid is added as a grinding aid to grind the granular powder or cut pieces. On the other hand, the heat-resistant temperature of flake powder of soft metal excluding tin is determined by the softening point, and even electrolytic copper with a low softening point is as high as 800°C. In addition, soft metals excluding tin do not have low-temperature brittleness and can be used at extremely low temperatures. The melting temperature of aluminum powder with a purity of 99.5% is 650°C. Therefore, even in harsh environments such as high temperature, extremely low temperature, vacuum, and high pressure, a film in which flat surfaces overlap and the powder is joined can be used. On the other hand, tin has a melting point of 232°C and causes low-temperature brittleness around -40°C, and only the film made of tin flake powder has a limited use temperature. In addition, the surface of the flake powder of soft metal is a flat and smooth surface, the thickness is nearly uniform, and the thickness is as thin as sub-microns. Also, the hardness of the flake powder of soft metal is low. Therefore, when a relatively small compressive stress is applied and compressed to a collection of flake powders in which flat surfaces overlap without gaps, the flat surfaces come into contact and the flat surfaces are joined. Since the area of the joint portion composed of flat surfaces is large, the bonding force between the flake powders is large. In addition, since the surface of the sheet in which flat surfaces are joined has a smooth surface close to a plane, the sheet has excellent lubricity. The use of the flake powder conforms to the use of the powder described in paragraphs 18 to 26. Among the second powders, there are flat powders made of soft magnetic alloys. That is, it is known that when soft magnetic powder is flattened in the plane direction, which is the direction of the easy axis of magnetization, the demagnetization factor becomes small, and the larger the flatness ratio, the greater the increase in the imaginary part μ” of the complex permeability. On the other hand, it is also known that the absorption of electromagnetic waves in soft magnetic materials depends on the magnitude of the imaginary part μ” of the complex permeability and the magnitude of the conductivity. Therefore, when using conductive soft magnetic flat powders, the performance of absorbing electromagnetic wave noise is improved. Furthermore, the flattening process of soft magnetic powder does not rely on the long-time batch process using a ball mill. Instead, atomized soft magnetic powder or reduced soft magnetic powder is processed by an attritor process using a media agitation type mill to produce soft magnetic flat powder. Thus, flat powder can be obtained continuously in a short time, and flat powder can be manufactured by an inexpensive processing method. Moreover, since a sheet is formed by aggregating flat powders where the flat surfaces directly overlap each other, a wide-area soft magnetic sheet can be formed with a small amount of flat powder used. Furthermore, more flat powders can participate in the absorption of electromagnetic waves, resulting in a soft magnetic sheet with high electromagnetic wave reception sensitivity and high performance in absorbing electromagnetic waves. This soft magnetic sheet maximally exhibits the flattening effect of the flat powder. Note that since the magnitude of the imaginary part of the complex permeability of the flat powder depends on the electromagnetic wave frequency band, the material of the flat powder is properly selected according to the frequency of the electromagnetic wave noise to be absorbed. Such flat powders of soft magnetic alloys include silicon steel powders with a silicon addition of less than 10%, permalloy powders with a nickel addition of 50% or less, sendust powders with an aluminum addition of at least 1 / 2 of the silicon addition, and electromagnetic stainless steel powders with an aluminum addition of less than 2%. That is, silicon steel becomes brittle and cannot be flattened as the silicon addition increases, so it is necessary to keep the silicon addition less than 10%. Also, when the silicon addition slightly varies, the magnetic permeability characteristics of silicon steel change significantly. Therefore, determine the silicon addition according to the required magnetic permeability characteristics. Furthermore, for permalloy, the manufacturing cost increases as the nickel addition increases, but the magnetic permeability decreases when the nickel addition is small, so keep the nickel addition at 50% or less. Therefore, determine the nickel addition according to the required magnetic permeability characteristics. Also, sendust is hard and brittle, but adding a small amount of aluminum and reducing the silicon addition enables flattening. Furthermore, since permendur is an alloy with cobalt, its manufacturing cost is high and it is not suitable for flat powders that absorb electromagnetic noise. Also, for electromagnetic stainless steel, adding aluminum makes flattening easier. The complex magnetic permeability of the soft magnetic flat powders composed of these four types of alloys changes significantly when the composition of components other than iron slightly varies. Also, since the hardness of the atomized powders or reduced powders of the four types of alloys differs depending on the alloy composition, the flatness ratio of the flat powders differs depending on the alloy composition, and the magnitude of the imaginary part of the complex magnetic permeability also differs. Furthermore, the frequency characteristics of the complex magnetic permeability vary greatly depending on the alloy composition. Therefore, for soft magnetic sheets used for absorbing electromagnetic waves or preventing electromagnetic noise interference, select the material of the soft magnetic flat powders according to the frequency band of the electromagnetic waves to be absorbed. Also, the hardness of the soft magnetic flat powders composed of the four types of alloys is higher than that of the flake powders composed of the above-mentioned soft metals. For this reason, the compression stress applied to the flat powders is large. Therefore, narrow the gap between the two work rolls according to the hardness of the flat powders. Also, even when a large compression stress is applied, the flat powders do not join together as a whole at the overlapping flat surfaces, so the bonding force between the flat powders is smaller than the bonding force between the flake powders composed of soft metals. Furthermore, the size of the soft magnetic flat powder composed of four types of alloys is nearly one order of magnitude smaller than that of the flake powder composed of the above-mentioned soft metal. Moreover, the aspect ratio of the soft magnetic flat powder composed of four types of alloys is close to that of the flake powder composed of the soft metal. Therefore, the thickness of the soft magnetic flat powder composed of four types of overlapping alloys is nearly one order of magnitude thinner than that of the flake powder composed of the soft metal. On the other hand, the thickness of the overlapping soft magnetic flat powder is nearly two orders of magnitude thinner than that of the fabric or non-woven fabric. Accordingly, for the thickness covering the entire fabric or non-woven fabric by the aggregation of the soft magnetic flat powder, by narrowing the gap between the two work rolls by nearly two orders of magnitude, the required compressive stress is applied to the aggregation of the soft magnetic flat powder, and the flat surfaces are joined together. The third powder includes a powder of metal oxide in a plate-like, flake-like, or scaly shape composed of alumina, mica, glass, or hematite. The scaly powder of the first alumina Al2O3 is produced by a method called the hydrothermal synthesis method in which aluminum hydroxide is reacted with water under high temperature and high pressure conditions. Incidentally, alumina has a high resistivity of 10 14 Ω·cm, a high hardness with a Mohs hardness of 9, and a high heat resistance exceeding 1500 °C that does not deteriorate due to frictional heat. Also, the thermal conductivity of the scaly powder of alumina is as small as 36 W / mK, providing a heat insulation effect. For example, when the size of the coating joined by friction pressure welding of the aggregation of the scaly powder of alumina is 100 cm × 100 cm and the thickness is 12 μm, the resistance of the coating composed of the aggregation of the scaly powder of alumina is 0.8×10 17It becomes Ω. Therefore, the sheet using alumina flake powder becomes an insulating sheet with extremely high insulation resistance. This insulating sheet can also be used as a refractory heat insulating material for high temperatures, a lining material for industrial furnaces such as heating furnaces and firing furnaces, and a sealing material. Also, the surface of the film has irregularities close to the size of the alumina flake powder and the irregularities on the surface of the alumina flake powder appearing on the surface of the film. Therefore, when the cut sheet is placed on the surface of a base material or component made of various materials and shapes and the surface of the cut sheet is evenly compressed, the convex portions of the irregularities on the surface of the film come into contact with the surface of the base material or component, and the cut sheet is joined to the surface of the base material or component by friction pressure welding at the contact portion. As a result, an insulating layer with extremely high insulation resistance and high heat resistance is formed on the surfaces of base materials or components of various materials. The second mica K2Al4(Al2Si6O 20 )(OH)4 (also called potassium aluminum silicate or mica), a flaky powder, can be obtained by finely pulverizing and purifying muscovite to obtain flaky mica powder. The mica powder has a high thermal decomposition temperature of 600 - 800 °C, an extremely small thermal conductivity of 0.67 W / mK, a certain strength with a tensile strength of 250 - 300 MPa, a large volume resistivity of 10 14 -10 16 Ω·cm, and a large dielectric breakdown voltage of 18 - 25 kV / 0.1 mm. Therefore, the sheet using mica powder becomes an insulating sheet with extremely high insulation resistance. This insulating sheet, like alumina, can also be used as a refractory heat insulating material for high temperatures, a lining material for industrial furnaces such as heating furnaces and firing furnaces, and a sealing material. Also, since the flaky powder of mica has a low Mohs hardness of 2.8 - 3.2, the film composed of an aggregation of the flaky powder of mica can be easily cut into an arbitrary shape. Furthermore, the surface of the film has irregularities close to the size of the flaky powder of mica and the irregularities on the surface of the flaky mica powder appearing on the surface of the film. Therefore, when the cut sheet is placed on the surface of a base material or component made of various materials and shapes and the surface of the cut sheet is evenly compressed, the convex portions of the irregularities on the surface of the film come into contact with the surface of the base material or component, and the cut sheet is joined to the surface of the base material or component by friction pressure welding at the contact portion. As a result, an insulating layer with extremely high insulation resistance and a large heat insulation effect is formed on the surfaces of base materials or components of various materials. Incidentally, the size of the flat alumina powder is nearly one digit smaller than the size of the flake powder made of the soft metal described above. Further, the aspect ratio of the flat alumina powder has a size close to the aspect ratio of the flake powder made of the soft metal. For this reason, the thickness of the flat alumina powder is nearly one digit thinner than the thickness of the flake powder made of the soft metal. Also, the alumina powder has a Mohs hardness close to 9 and is a hard powder that does not undergo plastic deformation. On the other hand, the thickness of the overlapping alumina powder is nearly two digits thinner than the thickness of the fabric or non-woven fabric. Therefore, with respect to the thickness covering the entire fabric or non-woven fabric with the alumina powder aggregate, by narrowing the gap between the two work rolls by nearly two digits, the required compressive stress is applied to the alumina powder aggregate, and the flat surfaces are joined together. In contrast, the mica flat powder has a width that differs by one digit in size. Also, the aspect ratio of the mica flat powder has a size close to the aspect ratio of the flake powder made of the soft metal. Also, the Mohs hardness of the mica flat powder is around 3 and it undergoes plastic deformation. Therefore, when the size of the mica flat powder is nearly one digit smaller than the size of the flake powder made of the soft metal, the thickness of the overlapping mica powder is nearly two digits thinner than the thickness of the fabric or non-woven fabric. Therefore, with respect to the thickness covering the entire fabric or non-woven fabric with the mica powder aggregate, by narrowing the gap between the two work rolls by nearly two digits, the required compressive stress is applied to the mica powder aggregate, and the flat surfaces are joined together. On the other hand, when the size of the mica flat powder is close to the size of the flake powder made of the soft metal, with respect to the thickness covering the entire fabric or non-woven fabric with the mica powder aggregate, by narrowing the gap between the two work rolls by nearly one digit, the required compressive stress is applied to the mica powder aggregate, and the flat surfaces are joined together. The third glass flake powder is produced by swelling molten glass into a hollow shape, reducing its film thickness, and then crushing it into flaky glass flake powder. The glass used in the production of glass flake powder is C glass and E glass. Since C glass contains 8 wt% of Na2O and K2O in its chemical composition, it is mainly used for applications that utilize its acid resistance properties. In contrast, E glass has a composition of only 0.3 wt% of Na2O and K2O and is used as a general-purpose glass. The density of E glass is 3 as small as 2.6 g / cm 15 , the softening point is 840 °C, the tensile strength is as large as 3.4 GPa, the thermal conductivity is as small as 1.03 W / mK, the volume resistivity is as large as 10 Ω·cm, the dielectric constant is 6.13 at 1 MHz, and the dielectric loss tangent is 0.0035 at 1 GHz, making it an excellent insulator. Therefore, a sheet composed of a collection of glass flake powder becomes a lightweight sheet with heat insulation, insulation, and tensile strength. Also, the Mohs hardness is 5 - 6, and the glass flake powder is cut by bending and breaking without producing chips. For this reason, a film composed of a collection of thin flake powder of glass can be cut into any shape. Furthermore, the surface of the film has irregularities close to the size of the glass flake powder. Therefore, when the cut sheet is placed on the surface of a substrate or component made of various materials and various shapes and the surface of the cut sheet is evenly compressed, the convex portions of the irregularities on the surface of the film come into contact with the surface of the substrate or component, and the cut sheet is joined to the surface of the substrate or component by frictional pressure bonding at the contact portion. As a result, a lightweight glass sheet layer with heat insulation, insulation, and tensile strength is formed on the surface of substrates or components made of various materials.The glass flake powder has a particle size close to that of the flake powder made of the soft metal described above, but is one digit thicker than the thickness of the flake powder made of the soft metal, has an aspect ratio close to that of the flake powder made of the soft metal, has a Mohs hardness of around 5, and has a value about twice that of the flake powder made of the soft metal, so it is difficult to undergo plastic deformation. On the other hand, the thickness of the overlapping glass flake powder is nearly one digit thinner than the thickness of the fabric or non-woven fabric. Therefore, for the thickness covering the whole of the fabric or non-woven fabric with the aggregation of glass flake powder, by narrowing the gap between the two work rolls by nearly one digit, the required compressive stress is applied to the aggregation of glass flake powder, and the flat surfaces are joined together. The fourth hematite (α-Fe2O3) powder is produced by hydrothermally treating yellow iron oxide (hydrated iron oxide α-FeOOH) in an alkaline aqueous solution to precipitate flaky hematite. The resistivity of hematite is as low as 10 8 Ω·cm as an insulator, but has a high melting point of 1565°C and is a non-combustible powder. Also, hematite powder is used as the red pigment (vermilion) of lacquerware. Therefore, the sheet using hematite powder becomes a sheet with excellent heat resistance and a vivid red color. Also, although hematite has a high Mohs hardness of 6.3, since the thickness of the film composed of the aggregation of hematite powder is thin, the sheet can be cut into any shape. Furthermore, the surface of the sheet has irregularities close to the size of the hematite scale powder and the irregularities on the surface of the hematite scale powder appearing on the surface of the sheet. Therefore, when the cut sheet is placed on the surface of a substrate or component made of various materials and shapes and the surface of the cut sheet is evenly compressed, the convex portions of the irregularities on the surface of the cut sheet come into contact with the surface of the substrate or component, and the cut sheet is joined to the surface of the substrate or component by friction welding at the contact portion, and a non-combustible layer with excellent heat resistance and a vivid red color is formed on the surface of the substrate or component. The flaky hematite powder has an average particle size as small as 12 - 15 μm and a thickness as thin as 0.2 - 0.3 μm. Therefore, similar to the flat powder of alumina powder, for the thickness covering the whole fabric or non-woven fabric with the aggregation of flaky hematite powder, by narrowing the gap between the two work rolls by nearly two digits, the required compressive stress is applied to the aggregation of flaky hematite powder, and the flat surfaces are joined together. Among the fifth powder, there is a powder of boron nitride having a flaky shape. Boron nitride BN consisting of a flaky hexagonal system does not exist in nature and is artificially manufactured. That is, boron carbide is fired in a high-temperature and high-pressure nitrogen pressurized atmosphere, the obtained fired product is mixed with a boron source, after raising the temperature to a temperature at which decarbonization can start, the temperature is raised to the high-temperature holding temperature in a nitrogen atmosphere and held in this atmosphere to obtain massive boron nitride. After that, the massive boron nitride is pulverized to obtain a flaky boron nitride powder consisting of a micron-sized hexagonal system. Boron nitride consisting of a hexagonal system has a layered structure similar to graphite particles. In the layer, boron atoms and nitrogen atoms are bonded by strong covalent bonds, but between the layers, they are held by weak van der Waals forces. Therefore, the layers are easily peeled off, and flakes made of massive boron nitride can be easily obtained. Thus, the flaky boron nitride powder consisting of a hexagonal system has anisotropy. For this reason, a film in which the flat surfaces, which are crystal planes, overlap each other acts as an excellent lubricating film. Also, since it does not react with corrosive chemicals and does not wet molten metal or molten glass, the film acts as a lubricating film with excellent corrosion resistance. Furthermore, the thermal conductivity in the direction parallel to the crystal plane is 410 W / mK, and the thermal conductivity in the direction perpendicular to the crystal plane is 2 W / mK. Therefore, in the film in which the flat surfaces, which are crystal planes, overlap each other, heat is easily conducted in the direction of the flat plane with high thermal conductivity, and the thermal conductivity of the film is close to the thermal conductivity in the direction parallel to the crystal plane and shows a thermal conductivity close to that of silver. Also, it is an excellent insulator with a dielectric constant of 3.9 and a resistivity of 10 15The film with a high resistivity of Ω·cm and overlapping flat crystal planes forms an insulating film with extremely high insulation resistance. Furthermore, since it has heat resistance at 900°C in an oxidizing atmosphere, 1200 - 1300°C in a vacuum, 2000°C in an inert atmosphere, and 3000°C under nitrogen pressure, it acts as an excellent thermal conductive sheet or insulating sheet in a high-temperature environment. Also, since the dielectric loss tangent is extremely low at 0.0008 at 1 MHz and the breakdown voltage is as high as 20 kV / mm, the film with overlapping flat crystal planes acts as an insulating sheet in the high-frequency region. Note that the flaky boron nitride powder has an average particle size ranging from 10 - 80 μm and an aspect ratio ranging from 2 - 30. Therefore, for flaky boron nitride powder with a relatively small average particle size and a relatively large aspect ratio, similar to the flat powder of alumina powder, by narrowing the gap between the two work rolls by nearly two orders of magnitude with respect to the thickness covering the entire fabric or non-woven fabric of the aggregation of flaky boron nitride powder, the required compressive stress is applied to the aggregation of flaky boron nitride powder, and the flat planes are joined together. For other aggregations of flaky boron nitride powder, by narrowing the gap between the two work rolls by nearly one order of magnitude with respect to the thickness covering the entire fabric or non-woven fabric of the aggregation of flaky boron nitride powder, the required compressive stress is applied to the aggregation of flaky boron nitride powder, and the flat planes are joined together. Note that since the flaky boron nitride powder has a Mohs hardness of less than 2, it undergoes plastic deformation under compressive stress. Therefore, since the flat planes are directly joined by friction pressure welding, the joint area is large, and the aggregation of boron nitride powder joined by friction pressure welding has excellent mechanical strength. As described above, among powders in the form of plates, flakes, or flakes with a large aspect ratio, there are powders of various materials. The powders composed of these 15 types of materials have unique properties according to the material. As a result, the sheet covered with the film formed by the aggregation of powders joined by friction pressure welding has the properties inherent to the powders. Therefore, the sheet can be used for various applications based on the properties inherent to the powders.

[0031] Using the flat powder of the four types of soft magnetic alloys described in paragraph 29, a method for continuously manufacturing a soft magnetic sheet that absorbs electromagnetic waves or a soft magnetic sheet that prevents electromagnetic noise interference is Among the flat powders composed of the four types of soft magnetic alloys described in paragraph 29, a plurality of types of soft magnetic flat powders having a magnitude of the imaginary part of the complex permeability that is equal to or greater than a certain value in different frequency bands are selected from the flat powders composed of the four types of soft magnetic alloys. The flat powders composed of the selected plurality of types of soft magnetic alloys are mixed at a predetermined ratio, and the collection of the flat powders composed of the mixed plurality of types of soft magnetic alloys is used as the powder described in paragraph 11, and all the processes of the three processes described in paragraph 11 are continuously carried out in order. This is a manufacturing method for continuously manufacturing a soft magnetic sheet that absorbs electromagnetic waves or a soft magnetic sheet that prevents electromagnetic noise interference.

[0032] That is, the four types of soft magnetic flat powders described in paragraph 30 have greatly different frequency characteristics of the imaginary part of the complex permeability depending on the composition of the alloy. Therefore, for soft magnetic sheets used for electromagnetic wave absorption or prevention of electromagnetic noise interference, the material of the soft magnetic flat powder is properly selected according to the frequency band of the electromagnetic waves to be absorbed. For this reason, if the magnitudes of the imaginary parts of the complex permeabilities of multiple types of soft magnetic flat powders are equal to or greater than a certain value in different frequency bands, these multiple types of soft magnetic flat powders are mixed, and the mixed soft magnetic flat powders are used as the powders described in paragraph 11, and according to the method for manufacturing the sheet described in paragraph 11, when a soft magnetic sheet is manufactured from a mixture of multiple types of soft magnetic flat powders, the soft magnetic sheet will have the effect of absorbing electromagnetic waves consisting of a wide frequency band or preventing interference of electromagnetic noise consisting of a wide frequency band. That is, among the flat powders composed of four types of soft magnetic alloys, multiple types of soft magnetic flat powders whose magnitudes of the imaginary parts of the complex permeabilities are equal to or greater than a certain value in different frequency bands are selected from the four types of soft magnetic alloys. Further, the selected multiple types of soft magnetic flat powders are mixed at a predetermined mixing ratio so that the magnitudes of the imaginary parts of the complex permeabilities of the multiple types of soft magnetic flat powders are equal to or greater than a certain value in different frequency bands. The aggregates of the mixed flat powders are stacked with their flat surfaces facing each other, and a soft magnetic sheet is formed from the aggregates of multiple types of soft magnetic flat powders with their flat surfaces joined together. The characteristic of the imaginary part of the complex permeability of this soft magnetic sheet is the imaginary part of the complex permeability obtained by adding the characteristics of the imaginary parts of the complex permeabilities of multiple types of soft magnetic flat powders. Therefore, the value of the imaginary part of the complex permeability has a certain magnitude in a wide frequency range. As a result, a soft magnetic sheet having the effect of absorbing electromagnetic waves or preventing interference of electromagnetic noise over a wide frequency band, which was impossible in the past, is obtained. For example, the peak value of the imaginary part of the complex permeability of permalloy flat powder is 9 at 3.3 MHz, and the peak value of the imaginary part of the complex permeability of silicon steel flat powder is 9 at 5.6 MHz. When a soft magnetic sheet is formed with a flat powder mixture of both at a 1:1 volume ratio, the value of the imaginary part of the complex permeability of the soft magnetic sheet has a wider frequency range with a constant value, for example, a value of 6 or more, compared to the case where each of the permalloy flat powder and the silicon steel flat powder forms a soft magnetic sheet alone. That is, the imaginary part of the complex permeability of the permalloy flat powder has a value of 6 or more in the frequency band of 1 - 6.7 MHz, and the imaginary part of the complex permeability of the silicon steel flat powder has a value of 6 or more in the frequency band of 3 - 10 MHz. However, for the mixed powder of both, the frequency band where the imaginary part of the complex permeability is 6 or more extends up to 1 - 10 MHz. Further, the peak value of the imaginary part of the complex permeability of electromagnetic stainless steel flat powder is 7.5 at 5 MHz. When a soft magnetic sheet is formed with a flat powder mixture of electromagnetic stainless steel flat powder, permalloy flat powder, and silicon steel flat powder at a 2:1:1 volume ratio, the imaginary part of the complex permeability of the soft magnetic sheet made of the mixed powder of permalloy flat powder and silicon steel flat powder dips and decreases in the frequency band of 4 - 6 MHz, but the imaginary part of the complex permeability in this valley frequency band is supplemented by the electromagnetic stainless steel flat powder. In this way, by mixing multiple types of soft magnetic flat powders at a predetermined mixing ratio so that the magnitudes of the imaginary parts of the complex permeabilities of the multiple types of soft magnetic flat powders have a value of a certain amount or more in different frequency bands, and using the mixed multiple types of soft magnetic flat powders as the powder described in paragraph 11 and manufacturing the sheet according to the method described in paragraph 11, when manufacturing a soft magnetic sheet with a mixture of multiple types of soft magnetic flat powders, the soft magnetic sheet becomes a soft magnetic sheet having the effect of absorbing electromagnetic waves or preventing electromagnetic noise interference over a wide frequency band.

Brief Description of the Drawings

[0033]

Figure 1

Mode for Carrying Out the Invention

[0034] Example 1 In this example, a sheet having a structure in which the entire fabric is covered with a film formed by an aggregation of spherical copper powder joined by friction pressure welding is continuously manufactured. The fabric is a plain-woven fabric made of 100% cotton yarn with a thickness of 0.5 mm, and a fabric piece with a width of 50 cm and a length of 10 m was used. Also, as the powder, spherical copper powder manufactured by the gas atomization method was used (FAM-QCU45-105μm of Fukuda Metal Foil & Powder Co., Ltd.). The size of the copper powder is 10 - 45 μm, the average particle size is 29.2 μm, 10%D is 16.4 μm, 50%D is 29.5 μm, and 90%D is 40.6 μm. Further, as the alcohol, 1-hexanol with a viscosity of 5.3 mPa·s at 20°C and a boiling point of 157°C was used. Note that 1-hexanol has a viscosity of 5.3 mPa·s at 20°C, and among alcohols having a viscosity of 3 - 11 mPa·s at 20°C, it cannot be said to be an alcohol with a low viscosity. On the other hand, the copper powder manufactured by the gas atomization method is spherical and has the best symmetry. Therefore, when subjected to compressive stress, many copper powders move to fill the voids in the aggregation of copper powders. However, the average particle size is 29.2 μm, which is small as the size of the powder. For this reason, it is necessary to confine the voids in the aggregation of copper powders joined by friction pressure welding by joining the overlapping copper powders. Also, since the copper powder is spherical, the plastic deformation of the copper powder is suppressed, and the adjacent voids cannot be filled by plastic deformation. For this reason, it is necessary to increase the number of overlapping copper powders. Note that the gap between the two work rolls cannot be narrowed because the plastic deformation of the copper powder is suppressed. For these reasons, 1-hexanol, which cannot be said to have a low viscosity, was used as the alcohol constituting the suspension, and after vaporizing 1-hexanol, copper powder with a relatively small powder size was stacked in the required number. First, in a container with a width of 52 cm, a length corresponding to the vertical width of 54 cm, and a depth of 8 cm, eight cylindrical rollers with a diameter of 3 cm are provided parallel to each other and spaced apart from each other across the entire width of the container on the side surface forming the width of the container. The driving device of the rollers continuously rotates them at the same peripheral speed of one rotation every 25 seconds. The first roller is provided such that the center of the roller is 3 cm away from one side surface forming the width of the container and 1.5 cm away from the upper end of the container. The first roller is provided so as to protrude 1.5 cm outside the container. The second roller is provided such that the center of the roller is 6 cm away from one side surface forming the width of the container and 3 cm away from the bottom surface of the container. The seventh roller is provided such that the center of the roller is 6 cm away from the other side surface forming the width of the container on the opposite side of the second roller and 3 cm away from the bottom surface of the container, the same as the second roller. The four rollers from the third to the sixth are provided such that the centers of the rollers are all 3 cm away from the bottom surface of the container, the same as the second roller and the seventh roller, and four rollers are provided with a 5.4 cm gap between the second roller and the seventh roller. The eighth roller is provided such that the center of the roller is 3 cm away from the other side surface forming the width of the container on the opposite side of the first roller and 1.5 cm away from the upper end of the container, the same as the first roller. The eighth roller is provided so as to protrude 1.5 cm outside the container. After that, a 12-stage rolling mill (for example, a product of Kobe Steel, Ltd.) was prepared. The two work rolls of the 12-stage rolling mill are cylinders with a diameter of 3 cm and a length of 52 cm. The gap between the two work rolls was set to 0.6 mm, and they were rotated in opposite directions at the same rotational speed as the rotational speed of the eight cylindrical rollers described above, and the temperature was raised to 167 °C, which is 10 °C higher than the boiling point of 1-hexanol, 157 °C. Next, 10 kg of copper powder and 12 kg of 1-hexanol were filled into the container, and 1-hexanol was stirred to create a suspension in which the copper powder was immersed in 1-hexanol. The suspension was such that six rollers from the second roller to the seventh roller were immersed in the suspension to form a depth of 5.2 cm. Furthermore, the fabric piece is set in the fabric pulling-out device, and the fabric is continuously pulled out from the fabric piece at a speed corresponding to the peripheral speed of the eight cylindrical rollers described above. The pulled-out fabric is brought into contact with the first roller of the container. Further, the fabric immersed in the suspension is continuously brought into contact from the second roller to the seventh roller. After that, the fabric in contact with the seventh roller advances with its moving direction changed upward, and after being pulled up from the suspension, it comes into contact with the eighth roller. The fabric in contact with the eighth roller changes its moving direction by 90 degrees and moves in the direction of the gap between the two work rolls constituting the multi-stage rolling mill. After that, the tip of the fabric immersed in the suspension is inserted into the gap between the two work rolls of the multi-stage rolling mill, and the fabric is compressed in the gap between the two work rolls. Further, the sheet discharged from the gap between the two work rolls is wound up by a winder rotating at the same speed as the rotational speed of the eight cylindrical rollers described above. Three sheets of the produced sheet were cut at a length of 50 cm, and the cut sheets were analyzed. First, the cut sheets were observed and analyzed with an electron microscope. As the electron microscope, the ultra-low acceleration voltage SEM of JFE Technoresearch Co., Ltd. was used. This device has the feature that surface observation can be performed with an ultra-low acceleration voltage starting from 100 volts, and the surface of the sample can be directly observed without forming a conductive film on the sample. The thickness of the sheet was 0.6 mm. Next, secondary electron beams between 900 and 1000 volts of the reflected electron beam from the cross section were extracted for image processing. Spherical powders that were partially plastically deformed formed 8 to 9 layers and were stacked on top of and below the organic matter with a thickness of 0.15 mm that was intermittently segmented, forming a joint with an average thickness of around 225 μm and covering the entire organic matter. Further, the energy and intensity of the characteristic X-rays were subjected to image processing to analyze the elements constituting the powder. As a result, it was found that the powder was copper. Therefore, in the created sheet, spherical copper powder forms 8 to 9 layers and overlaps over the entire fabric. Further, the aggregates of copper powder and the fabric are compressed, the part of the fabric in contact with the copper powder is broken, and the fabric is intermittently divided. The copper powder enters the broken part. Further, a part of the copper powder is plastically deformed, and all contact parts between the copper powders are joined by friction pressure welding. The aggregates of copper powder joined by friction pressure welding cover the intermittently divided fabric. In Fig. 1, the cross-section of the sheet having a structure in which the aggregates of copper powder joined by friction pressure welding are joined to the entire divided fabric is schematically enlarged and shown. 1 is copper powder, and 2 is the divided fabric. In addition, the thickness of the film formed by joining overlapping copper powders with 8 - 9 layers formed was around 225 μm by friction compression. This film thickness was thin compared to the size of the overlapping copper powder particles. That is, it is considered that the thickness of the overlapping copper powders that did not undergo plastic deformation and formed 8 - 9 layers reached an average of 240 - 270 μm. Also, the thickness of the fabric is close to 0.5 mm. On the other hand, in the results of Example 1, the thickness of the divided fabric is 0.15 mm, and the thickness of the copper powder joined by friction compression is 0.225 mm. Therefore, it can be said that the spherical copper powder was plastically deformed at a rate of 6 - 17%. Copper has a low hardness and is prone to plastic deformation, but due to the spherical shape of the copper powder, the plastic deformation of the copper powder was suppressed. That is, in Example 1, when the fabric evenly covered with the suspension approached the gap between the two work rolls, 1 - hexanol vaporized from the suspension. After that, the fabric evenly covered with the aggregation of copper powder was drawn into the gap between the two work rolls. First, the surface layer of the aggregation of copper powder came into contact with the two work rolls, and the surface layer of the aggregation of copper powder moved backward. After that, compressive stress was applied to the fabric evenly covered with the aggregation of copper powder. First, the copper powder moved to fill the voids in the aggregation of copper powder. When the movement of the copper powder became difficult, compressive stress was applied to the aggregation of copper powder and the fabric, and plastic deformation of the copper powder began. Also, the fabric underwent plastic deformation, and furthermore, breakage of the fabric by the copper powder began. When the plastic deformation of the copper powder was completed, the breakage of the fabric was completed, and the fabric was divided, frictional heat was generated at the contact parts between the copper powders, and all the contact parts were joined by friction welding. The broken part of the fabric was also filled with copper powder joined by friction welding. As a result, the aggregation of copper powder in which the copper powders that had completed plastic deformation were joined at the contact parts covered the entire intermittently divided fabric. As a result, a film composed of an aggregation of copper powder in which overlapping copper powders with 8 - 9 layers formed were joined by friction compression formed a thickness of around 225 μm. Next, a part of the cut sheet was immersed in water. After that, the sheet was lifted out of the water and the surface was observed. As a result, several water droplets were present on the surface. When the sheet was tilted diagonally, the water droplets easily fell, so the surface of the sheet has water repellency. Furthermore, the surface resistance at multiple locations on the sheet surface was measured using a surface resistance meter (Surface Resistance Meter ST - 4 of Simco Japan Co., Ltd.). The surface resistance values were all 1×103 The surface resistance of the sample was less than Ω / □, close to that of metal. After this, the gas permeability was examined using a gas permeability measuring device (a product of GTR Tech Co., Ltd.) using the JISK7126A method (differential pressure method) and differential pressure gas chromatography, and it was found that air does not permeate at atmospheric pressure. Therefore, the cut sheet is non-flammable and has the heat resistance of copper. Furthermore, the tensile strength of a portion of the cut sheet was tested according to JIS C6515, a copper foil test method for printed wiring boards, and the result was 400±20MPa. This figure is close to the tensile strength of 450MPa of copper foil made of 12μm thick tough pitch copper rolled with low roughness, so it was found to have sufficient mechanical strength as a sheet. For this reason, the cut sheet can be used as a lightweight conductive sheet or heat conductive sheet, or as a substrate or electrode for electric circuits. The cut sheet was then further cut into pieces measuring 10cm x 10cm, and placed on top of a 1mm thick plastic sheet measuring 10cm x 10cm. Nine 10kg weights were placed at equal intervals on the surface of the overlapped sheets to bond the sheets together. Next, the bonding strength of the bonded surfaces was examined at a peel speed of 300mm / min in accordance with the 180-degree peel test of JIS Z0237:2022 (Test method for adhesive tapes and adhesive sheets). The peel force was 280mN / 50mm, indicating sufficient bonding strength. This provides the surface of the plastic sheet with the electrical and thermal conductivity of copper. In this embodiment, spherical copper powder produced by gas atomization is used as a representative of powders having a spherical, granular, or agglomerated shape. However, the present invention is not limited to spherical copper powder produced by gas atomization, and powders having a spherical, granular, or agglomerated shape made of various materials as described in paragraph 18 can be used.

[0035] Example 2 In this example, a sheet having a structure in which a fabric remnant used in Example 1 is covered with a film formed by aggregating sponge-like iron powder joined by friction pressure welding is continuously manufactured. As the iron powder, pure iron powder (JIP300A of JFE Steel Corporation) manufactured by the water atomization method was used. Since the iron powder was manufactured by the water atomization method, it has a dense structure consisting of a sponge shape and is not porous like iron powder manufactured by the reduction method. The median diameter at which the cumulative distribution becomes 50% is 77.0 μm, and the green density is 6.86 g / cm 3 ³. The particle size distribution is 27.8% for +106 μm, 23.7% for +75 μm, 9.6% for +63 μm, 14.9% for +45 μm, and 24.0% for -45 μm. As the alcohol, 2-heptanol having a viscosity of 4.0 mPa·s at 20 °C and a boiling point of 159 °C was used. Note that 2-heptanol has a viscosity of 4.0 mPa·s at 20 °C and is lower than the viscosity of 1-hexanol used in Example 1. On the other hand, the copper powder manufactured by the gas atomization method in Example 1 is spherical with the most excellent symmetry, while the iron powder manufactured by the water atomization method in Example 2 is sponge-like and has inferior symmetry compared to the copper powder. However, the size of the iron powder manufactured by the water atomization method is nearly three times larger on average than the size of the copper powder manufactured by the gas atomization method. For this reason, the surface area of the iron powder is larger than the surface area of the copper powder. Therefore, 2-heptanol, which has a lower viscosity than 1-hexanol used in Example 1, was used as the alcohol constituting the suspension, and after vaporizing 2-heptanol, the iron powder having a relatively large particle size was stacked in a smaller number of sheets than the copper powder in Example 1. Furthermore, when the aggregate of iron powder is compressed, since the iron powder has a sponge-like shape, the plastically deformed iron powder fills the adjacent voids. For this reason, the gap between the two work rolls was made narrower than that of the spherical copper powder in Example 1, and a large compressive stress was applied to the sponge-like iron powder, and the voids in the aggregate of iron powder were filled by the plastic deformation of the iron powder. Therefore, the gap between the two work rolls was set to 0.4 mm. Also, the container used in Example 1 was employed, and eight cylindrical rollers were installed in this container in the same manner as in Example 1. Furthermore, the 12-stage rolling mill used in Example 1 was utilized. However, the gap between the two work rolls was set to 0.4 mm, and the temperature was raised to 169 °C, which is 10 °C higher than the boiling point of 2-heptanol. Next, 10 kg of iron powder and 12 kg of 2-heptanol were filled into the container, and the 2-heptanol was stirred to create a suspension in which the iron powder was immersed. Note that, in order to form a depth of 5.2 cm, six rollers from the second roller to the seventh roller were immersed in the suspension. Furthermore, in the same manner as in Example 1, the fabric reactant was set in the pulling-out device, and the fabric was continuously pulled out from the reactant at a speed corresponding to the peripheral speed of the eight cylindrical rollers, and the pulled-out fabric was brought into contact with the first roller of the container. Further, the fabric immersed in the suspension was continuously brought into contact with the second roller to the seventh roller. After that, the fabric that has contacted the seventh roller advances with its moving direction changed upward, and after being pulled up from the suspension, it contacts the eighth roller. The fabric that has contacted the eighth roller changes its moving direction by 90 degrees and moves in the direction of the gap between the two work rolls of the multi-stage rolling mill, and the tip of the fabric immersed in the suspension is inserted into the gap between the two work rolls, and the fabric is compressed in the gap between the two work rolls. Furthermore, the sheet discharged from the gap between the two work rolls was wound up by a winder rotating at the same speed as the rotational speed of the eight cylindrical rollers. Three sheets of the created sheet were cut at a length of 50 cm, and the cut sheets were analyzed. First, in the same manner as in Example 1, the cut sheet was observed and analyzed with an electron microscope. The thickness of the sheet was 0.4 mm. Next, secondary electron beams between 900 and 1000 volts of the reflected electron beam from the cross-section were extracted for image processing. Plastic-deformed powder formed six to seven layers and overlapped on the upper and lower sides of the intermittently segmented organic matter with a thickness of 0.05 mm, forming an average thickness of around 170 μm and joining to cover the entire segmented organic matter. Furthermore, the energy and intensity of the characteristic X-rays were subjected to image processing to analyze the elements constituting the powder. As a result, it was found that the powder was iron. Therefore, in the created sheet, the sponge-like iron powder forms 6-7 layers over the entire fabric and overlaps, the part of the fabric in contact with the iron powder breaks, the iron powder enters the broken part, all contact parts between the iron powders plastically deform and are joined by friction welding, and the aggregates of the iron powders joined by friction welding cover the intermittently divided fabric. Incidentally, the thickness of the film formed by joining iron powders that were formed into 6 - 7 layers and overlapped by friction compression was around 170 μm. On the other hand, the thickness of the collection of iron powders that were formed into 6 - 7 layers and overlapped before compression is considered to reach 450 - 520 μm. Also, the thickness of the fabric is close to 0.5 mm. Therefore, since the gap between the two work rolls of the multi - stage rolling mill is 0.4 mm, the thickness of the fabric evenly covered with the collection of iron powders has a thickness nearly 3.5 - 3.8 times that. On the other hand, the result of Example 2 is that the thickness of the divided fabric is 0.05 mm and the thickness of the iron powders joined by friction compression is around 0.17 mm. Therefore, the sponge - like iron powders are plastically deformed at an average rate of around 65% and are joined by friction welding. That is, when the fabric evenly covered with the suspension approaches the gap between the two work rolls, 2 - heptanol vaporizes from the suspension, and then the fabric evenly covered with the collection of iron powders is drawn into the gap between the two work rolls. Further, the surface layer of the collection of iron powders comes into contact with the two work rolls, and the surface layer of the collection of iron powders moves backward. After that, compressive stress is applied to the fabric evenly covered with the collection of iron powders. First, the iron powders move to fill the voids in the collection of iron powders. When the movement of the iron powders becomes difficult, compressive stress is applied to the collection of iron powders and the fabric, and plastic deformation of the iron powders begins, and also compressive deformation of the fabric begins, and further, breakage of the fabric compressed by the iron powders begins. Furthermore, when the plastic deformation of the iron powders is completed and the breakage of the fabric is completed, frictional heat is generated at the contact portions between the plastically deformed iron powders, and all the contact portions are joined by friction welding, and the broken portions of the fabric are also filled with the iron powders joined by friction welding. As a result, the entire intermittently divided fabric is covered with a collection of iron powders where the plastically deformed iron powders overlap and are joined. As a result, a film with a thickness of around 170 μm is formed, which consists of a collection of iron powders joined by friction compression where the iron powders formed into 6 - 7 layers and overlapped. Incidentally, the atomized iron powder of JFE Steel Corporation has a high carbon content and oxygen content in the raw powder obtained in the atomization process and is hard, so the hardness is reduced by decarburization and reduction treatment in a reduction heat treatment furnace. Next, a part of the cut sheet was immersed in water, and then the sheet was lifted out of the water and its surface was observed. As a result, several water droplets were present on the surface, and when the sheet was tilted obliquely, the water droplets easily fell, so the surface of the sheet was water-repellent. Furthermore, the surface resistance at multiple locations on the sheet surface was measured using a surface resistance meter (Surface Resistance Meter ST-4 of Simco Japan Co., Ltd.). The surface resistance values were all less than 1×10 3 Ω / square, and the sample had a value close to the surface resistance of metal. After that, using a part of the cut sheet, the gas permeability was examined with a gas permeability measuring device (product of GTR Tech Co., Ltd.) by the differential pressure type gas chromatography method of JIS K7126A method (differential pressure method). As a result, it was found that air did not permeate at atmospheric pressure. Therefore, the sheet is non-combustible and has the heat resistance of iron. Furthermore, using a part of the cut sheet, the tensile strength was examined based on the copper foil test method for printed wiring boards JIS C6515. As a result, the tensile strength was 440±10 MPa. Since this value is close to the tensile strength of 450 MPa of a 12 μm thick copper foil obtained by low roughness rolling of tough pitch copper, it was found that the sheet has sufficient mechanical strength. Therefore, the manufactured sheet, or the cut sheet, or the bent sheet effectively acts as a shielding sheet for shielding magnetism. Also, in the same manner as in Example 1, the cut sheet was further cut into a size of 10 cm×10 cm and superimposed on the surface of a plastic sheet with a thickness of 1 mm and a size of 10 cm×10 cm. Nine weights of 12 kg were placed on the surface of the superimposed sheets at equal intervals, and the sheets were joined together. Next, in accordance with the 180-degree peel test of JIS Z0237:2022 (Adhesive Tape and Adhesive Sheet Test Method), the joining strength of the joint surface was examined at a peel rate of 300 mm / min. Since the peel force was 320 mN / 50 mm, sufficient joining strength was obtained. Therefore, the surface conductivity and magnetic properties of iron were imparted to the surface of the plastic sheet. In addition, in this embodiment, although it has a spongy shape but is not porous and plastically deforms when compressed, iron powder produced by the water atomization method was used as the powder. However, not limited to the iron powder produced by the water atomization method, bronze powder of an alloy composed of copper and tin produced by the water atomization method described in paragraph 22 can be used.

[0036] Example 3 In this embodiment, a sheet having a structure covered with a film in which a collection of teardrop-shaped aluminum powder joined by friction pressure welding is formed is continuously produced on the waste of the nonwoven fabric. The nonwoven fabric is made of polypropylene, has a thickness of 250 μm, and a waste of 50 cm × 10 m was used. The aluminum powder is teardrop-shaped produced by the gas atomization method and has an average particle size of 24 - 27 μm (350M of Mineralco Co., Ltd.). As the alcohol, 3-pentanol having a viscosity of 6.5 mPa·s at 20°C and a boiling point of 116°C was used. Incidentally, 3-pentanol has a viscosity of 6.5 mPa·s at 20°C, which is slightly higher than the viscosity of 1-hexanol used in Example 1. On the other hand, the copper powder produced by the gas atomization method in Example 1 is spherical with the most excellent symmetry, while the aluminum powder produced by the gas atomization method in Example 3 is teardrop-shaped and has inferior symmetry compared to the copper powder, but is more prone to plastic deformation than the spherical copper powder. On the other hand, the size of the aluminum powder produced by the gas atomization method is slightly smaller than the size of the copper powder produced by the gas atomization method. For this reason, the surface area of the aluminum powder is slightly narrower than the surface area of the copper powder. Considering the ratio of plastic deformation, 3-pentanol, which has a slightly higher viscosity than 1-hexanol used in Example 1, was used as the alcohol constituting the suspension. After vaporizing 3-pentanol, the aluminum powder with inferior symmetry was stacked in a larger number than the copper powder in Example 1. Also, when compressing the agglomeration of aluminum powder, since the aluminum powder with low hardness is teardrop-shaped, it is more prone to plastic deformation than the spherical copper powder in Example 1, and the plastically deformed aluminum powder fills the adjacent voids. For this reason, the gap between the two work rolls was made narrower than that in Example 1 for the spherical copper powder, and a larger compressive stress was applied to the teardrop-shaped aluminum powder, and the voids in the agglomeration of aluminum powder were filled by the plastic deformation of the aluminum powder. Therefore, the gap between the two work rolls was set to 0.3 mm, which is half of that in Example 1. The container used in Example 1 was used, and eight cylindrical rollers were installed in this container in the same manner as in Example 1. Incidentally, the eight cylindrical rollers were continuously rotated at the same peripheral speed of rotating once every 25 seconds, as in Example 1. Further, the 12-stage rolling mill used in Example 1 was used. However, the gap between the two work rolls was set to 0.3 mm, and the temperature was raised to 126°C, which is 10°C higher than the boiling point of 3-pentanol, 116°C. Next, 10 kg of aluminum powder and 12 kg of 3-pentanol were filled into the container, and 3-pentanol was stirred to create a suspension in which the aluminum powder was immersed in 3-pentanol. Incidentally, since the suspension forms a depth of 5.2 cm, six rollers from the second roller to the seventh roller are immersed in the suspension. Furthermore, the non-woven fabric web was set in a drawing device, and the fabric was continuously drawn from the non-woven fabric at a speed corresponding to the peripheral speed of eight cylindrical rollers. The drawn fabric was brought into contact with the first roller of the container. Further, the fabric immersed in the suspension was continuously brought into contact from the second roller to the seventh roller. After that, the fabric in contact with the seventh roller advances with its moving direction changed upward. After being pulled out from the suspension, it comes into contact with the eighth roller. The fabric in contact with the eighth roller changes its moving direction by 90 degrees and moves in the direction of the gap between the two work rolls of the multi-stage rolling mill. The tip of the fabric immersed in the suspension is inserted into the gap between the two work rolls of the multi-stage rolling mill, and the fabric is compressed in the gap between the two work rolls. Further, the sheet discharged from the gap between the two work rolls was wound up by a winder rotating at the same speed as the rotational speed of the eight cylindrical rollers. The prepared sheet was cut into three pieces each with a length of 50 cm, and the cut sheets were analyzed. First, in the same manner as in Example 1, the cut sheet was observed and analyzed with an electron microscope. The thickness of the sheet was 0.3 mm. Next, secondary electron beams between 900 and 1000 volts of the reflected electron beam from the cross-section were extracted for image processing. Plastic-deformed teardrop-shaped powder formed 11 - 12 layers and overlapped on the upper and lower sides of the organic matter with a thickness of 0.05 mm that was intermittently segmented, forming a thickness of approximately 75 μm on average and joining to cover the entire intermittently segmented organic matter. Further, the energy and intensity of the characteristic X-rays were subjected to image processing to analyze the elements constituting the powder. As a result, it was found that the powder was aluminum. Therefore, in the prepared sheet, easily plastically deformable teardrop-shaped aluminum powder formed 11 - 12 layers and overlapped over the entire non-woven fabric. The part of the non-woven fabric in contact with the aluminum powder broke, and the aluminum powder entered the broken part. All the contact parts between the aluminum powders were plastically deformed and joined by friction welding. The aggregates of aluminum powder joined by friction welding covered the intermittently segmented non-woven fabric. Note that the thickness of the coating formed by joining aluminum powders that formed 11 - 12 layers and overlapped with each other by friction compression was around 75 μm. This thickness of the coating is too thin compared to the size of the aluminum powder particles. The thickness of the aluminum powder before compression that formed 11 - 12 layers and overlapped with each other is considered to reach 265 - 320 μm. Also, the thickness of the non - woven fabric is close to 0.25 mm. Therefore, since the gap between the two work rolls of the multi - stage rolling mill is 0.3 mm, the non - woven fabric evenly covered with an aggregate of aluminum powder has a thickness that is 2.6 - 3.0 times thicker. On the other hand, in the result of Example 3, the thickness of the divided non - woven fabric is 0.05 mm, and the thickness of the teardrop - shaped aluminum powder joined by friction compression is around 0.075 mm. Therefore, the teardrop - shaped aluminum powder has undergone plastic deformation at a rate of 70 - 76% and has been joined by friction pressure welding. That is, when the non - woven fabric evenly covered with the suspension approaches the gap between the two work rolls, 3 - pentanol vaporizes from the suspension. After that, the non - woven fabric evenly covered with an aggregate of aluminum powder is drawn into the gap between the two work rolls, and furthermore, the surface layer of the aggregate of aluminum powder comes into contact with the two work rolls, and the surface layer of the aggregate of aluminum powder moves backward. After that, compressive stress is applied to the non - woven fabric evenly covered with an aggregate of aluminum powder. First, the aluminum powder moves to fill the voids in the aggregate of aluminum powder. When the movement of the aluminum powder becomes difficult, compressive stress is applied to the aggregate of aluminum powder and the non - woven fabric, and plastic deformation of the aluminum powder begins, and also compressive deformation of the non - woven fabric begins, and furthermore, breakage of the non - woven fabric by the aluminum powder begins. Furthermore, when the plastic deformation of the aluminum powder is completed and the breakage of the non - woven fabric is completed, frictional heat is generated at the contact portions between the plastically deformed aluminum powders, and all the contact portions are joined by friction pressure welding, and the broken portions of the non - woven fabric are also filled with aluminum powder joined by friction pressure welding. As a result, the entire non - woven fabric intermittently divided is covered with an aggregate of aluminum powders where the plastically deformed aluminum powders overlap and are joined. As a result, a coating with a thickness of around 75 μm is formed, which consists of an aggregate of aluminum powders where aluminum powders that formed 11 - 12 layers and overlapped with each other are joined by friction compression. Next, a part of the cut sheet was immersed in water. After that, the sheet was lifted out of the water and its surface was observed. As a result, several water droplets were present on the surface, and when the sheet was tilted diagonally, the water droplets easily fell off. Therefore, the surface of the sheet has water repellency. Furthermore, the surface resistance at multiple locations on the sheet surface was measured using a surface resistance meter (Surface Resistance Meter ST-4 manufactured by Simco Japan Co., Ltd.). All of the surface resistance values were less than 1×10 3 Ω / □, and the sample had a value close to the surface resistance of metal. After that, using a part of the cut sheet, the gas permeability was examined by a differential pressure type gas chromatography method of the JIS K7126A method (differential pressure method) using a gas permeability measuring device (product of GTR Tech Co., Ltd.). As a result, it was found that air did not permeate at atmospheric pressure. Therefore, the sheet has nonflammability and also has the heat resistance of iron. Furthermore, using a part of the cut sheet, the tensile strength was examined based on the copper foil test method for printed wiring boards JIS C6515. As a result, the tensile strength was 470 ± 10 MPa. Since this value is close to the tensile strength of 450 MPa of a 12 μm thick copper foil obtained by low roughness rolling of tough pitch copper, it was found that the sheet has sufficient mechanical strength. Note that since aluminum powder has high conductivity and high thermal conductivity like copper powder, a sheet composed of a structure covered with an aggregate of aluminum powder joined by friction pressure welding, or a cut sheet, is used as a lightweight conductive sheet, a lightweight heat sink, a heat conduction sheet, a substrate for an electric circuit, or an electrode. Also, in the same manner as in Example 1, the cut sheet was further cut into a size of 10 cm × 10 cm and placed on the surface of a plastic sheet with a thickness of 1 mm and a size of 10 cm × 10 cm. Nine weights of 9 kg were placed on the surface of the stacked sheets at equal intervals, and the sheets were joined together. Next, in accordance with the 180-degree peel test of JIS Z0237:2022 (Adhesive Tape and Adhesive Sheet Test Method), the joining strength of the joint surface was examined at a peel rate of 330 mm / min. Since the peel force was 350 mN / 50 mm, sufficient joining strength was obtained. Therefore, both the electrical conductivity and the thermal conductivity of aluminum are imparted to the surface of the plastic sheet. In this example, teardrop-shaped or spindle-shaped powder that is plastically deformed when compressed, tear-drop-shaped aluminum powder manufactured by a gas atomization method was used. However, not limited to the aluminum powder manufactured by the gas atomization method, powders having a teardrop shape or a spindle shape made of various materials described in paragraph 26 and plastically deformed when compressed can be used.

[0037] Example 4 In this example, a sheet having a structure covered with a film formed by aggregating flat alumina powder joined by friction pressure welding is continuously manufactured on the nonwoven fabric used in Example 3. The flat alumina powder is flat powder manufactured by a hydrothermal synthesis method, has an aspect ratio of 30 on average and a small average particle size of 9 μm (BMF series of Kawai Lime Industry Co., Ltd.). Therefore, the average thickness of alumina is as thin as 0.3 μm. Further, the flat alumina powder has a high hardness with a Mohs hardness of around 9 depending on the purity of alumina. Therefore, the flat alumina powder does not deform by compressive stress. For this reason, when compressive stress is applied, the gap between the flat surfaces of alumina narrows and the deformation of the nonwoven fabric progresses, but the flat alumina powder does not deform, the flat surfaces come into contact with each other, and the contact portions between the flat surfaces are joined by friction pressure welding. Further, isooctyl alcohol having a viscosity of 10.6 mPa·s at 20°C and a boiling point of 188°C was used as the alcohol. Note that isooctyl alcohol has a viscosity of 10.6 mPa·s at 20°C, which is higher than the viscosity of any of the alcohols used in Examples 1-3. That is, the flat alumina powder manufactured by the hydrothermal synthesis method in Example 4 has an average particle size of 9 μm, which is significantly smaller than any of the powders used in Examples 1-3. For this reason, the surface area of the alumina powder is significantly smaller than the surface area of any of the powders used in Examples 1-3. Further, the alumina powder does not plastically deform. Therefore, it is necessary to use isooctyl alcohol, which has a higher viscosity than the alcohols used in Examples 1-3, as the alcohol constituting the suspension, and after vaporizing the isooctyl alcohol, stack the alumina powder in a larger number of sheets than the powders used in Examples 1-3. Moreover, the powder used is flat powder that does not undergo plastic deformation, and furthermore, the average thickness is as thin as 0.3 μm. Therefore, even when the non-woven fabric with the flat powder attached is compressed, the flat powder does not break but only undergoes compressive deformation. On the other hand, although the thickness of the non-woven fabric is close to 0.25 mm, the gap between the two work rolls is as narrow as 0.07 mm. Therefore, the non-woven fabric in the manufactured sheet is crushed to a thickness of 1 / 4 - 1 / 5 by the compressive stress. The container used was the container used in Example 1, and eight cylindrical rollers were installed in this container in the same manner as in Example 1. The eight cylindrical rollers were continuously rotated at the same peripheral speed of one rotation every 25 seconds, as in Example 1. Furthermore, the 12-stage rolling mill used in Example 1 was used. However, since the alumina powder does not undergo plastic deformation in the thickness direction, the gap between the two work rolls was set to a narrow gap of 0.07 mm, and the temperature was raised to 198 °C, which is 10 °C higher than the boiling point of isooctyl alcohol, 188 °C. Next, 10 kg of alumina powder and 12 kg of 1-heptanol were filled into the container, and 1-heptanol was stirred to create a suspension in which the aluminum powder was immersed in 1-heptanol. The suspension was such that six rollers from the second roller to the seventh roller were immersed in the suspension to form a depth of 5.2 cm. Furthermore, the reactant of the non-woven fabric was set in the drawing device, and the fabric was continuously drawn from the non-woven fabric at a speed corresponding to the peripheral speed of the eight cylindrical rollers. The drawn fabric was brought into contact with the first roller of the container, and further, the fabric was continuously brought into contact with the rollers from the second roller to the seventh roller. After that, the fabric that had contacted the seventh roller advanced with its moving direction changed upward. After being pulled out from the suspension, it contacted the eighth roller. The fabric that had contacted the eighth roller changed its moving direction by 90 degrees and moved in the direction of the gap between the two work rolls of the multi-stage rolling mill. The tip of the fabric immersed in the suspension was inserted into the gap between the two work rolls of the multi-stage rolling mill, and the fabric was compressed by the gap between the two work rolls. Furthermore, the sheet discharged from the gap between the two work rolls was wound up by a winder that rotated at the same speed as the rotational speed of the eight cylindrical rollers. Three sheets of the created sheet were cut at a length of 50 cm, and the cut sheets were analyzed. First, as in Example 1, the cut sheet was observed and analyzed with an electron microscope. The thickness of the sheet was 0.07 mm. Next, secondary electrons between 900 and 1000 volts of the reflected electron beam from the cross-section were extracted and image processing was performed. On the top and bottom of the organic matter with a thickness of 0.055 mm, fine flat powders were stacked with 24 - 25 layers formed by flat surfaces facing each other, forming a thickness of around 7.4 μm on average and joining to cover the entire organic matter. Furthermore, the energy and intensity of characteristic X-rays were image-processed to analyze the elements constituting the powder. As a result, it was found that the powder was alumina. Therefore, in the created sheet, fine flat alumina powders were stacked with 24 - 25 layers formed by flat surfaces facing each other over the entire non-woven fabric, and the flat surfaces of the overlapping alumina powders were joined by friction pressure welding. The collection of alumina powders joined by friction pressure welding covered the non-woven fabric crushed by compressive stress. The thickness of this collection of alumina powders is close to the size of the alumina powders before compression. That is, if the gap between flat surfaces is 10% of the average thickness of alumina, the thickness formed by 24 - 25 layers of overlapping alumina powders before compression is considered to be around 8 μm on average. Also, the thickness of the non-woven fabric is close to 0.25 mm. Therefore, the thickness of the non-woven fabric evenly covered with the collection of alumina powders is close to 266 μm on average. Since the gap between the two work rolls of the multi-roll rolling mill is 0.07 mm, the thickness of the non-woven fabric evenly covered with the collection of flat alumina powders is nearly 3.8 times thicker. On the other hand, the result of Example 4 shows that the thickness of the non-woven fabric crushed by compressive stress is close to 55 μm, and the thickness of the collection of flat alumina joined by friction pressure welding is around 7.4 μm on average. Therefore, the flat alumina powders did not deform in the thickness direction and were joined by frictional heat between flat surfaces. As a result, a sheet with a thickness of 70 μm was formed. That is, when the nonwoven fabric evenly covered with the suspension approaches the gap between the two work rolls, 1-heptanol vaporizes from the suspension. Thereafter, the nonwoven fabric evenly covered with the aggregates of alumina powder in which the flat powders overlap is drawn into the gap between the two work rolls. Further, the surface layer of the aggregates of the flat alumina powders contacts the two work rolls, and the surface layer of the aggregates of the flat alumina powders moves backward. Next, a compressive stress is applied to the nonwoven fabric evenly covered with the aggregates of alumina powder in which the flat powders overlap. First, the gap between the flat surfaces in the aggregates of alumina powder in which the flat powders overlap narrows, and the compression deformation of the nonwoven fabric starts. Further, the compression deformation of the nonwoven fabric by the flat alumina powders proceeds. Thereafter, the joining of the contact portions between the flat surfaces of the flat alumina powders starts, and the compression deformation of the nonwoven fabric by the flat alumina powders further proceeds. Further, the joining of the contact portions between the flat surfaces of the flat alumina powders is completed, and the compression deformation of the nonwoven fabric is completed. As a result, a film having a thickness of around 7.8 μm is formed from the aggregates of the flat alumina powders that are joined by friction compression and are formed in 24-25 layers and overlap each other. Also, the nonwoven fabric is crushed by the compressive stress to a thickness of 55 μm. Next, a part of the cut sheet was immersed in water. Thereafter, the sheet was lifted out of the water, and the surface was observed. As a result, several water droplets were present on the surface. When the sheet was tilted obliquely, the water droplets easily fell. Therefore, the surface of the sheet has water repellency. Furthermore, when the surface resistance at a plurality of locations on the surface of the cut sheet was measured with an insulation resistance meter, the needle was broken off, and the resistance value was larger than 100 MΩ. Also, the static friction coefficient and the dynamic friction coefficient of the plurality of surfaces of the cut sheet were measured with a measuring device (a friction coefficient measuring device composed of an autograph AGS-X, a tabletop precision universal testing machine manufactured by Shimadzu Corporation). The static friction coefficient was 0.15 ± 0.03, and the dynamic friction coefficient was 0.10 ± 0.02. Both friction coefficients are small. After that, using a part of the cut sheet, the gas permeability was examined by a differential pressure type gas chromatography method of JIS K7126A method (differential pressure method) using a gas permeability measuring device (product of GTR Tech Co., Ltd.). As a result, it was found that air did not permeate at atmospheric pressure. Therefore, the sheet has incombustibility and also has the heat resistance of iron. Furthermore, using a part of the cut sheet, the tensile strength was examined based on the copper foil test method for printed wiring boards JIS C6515. As a result, the tensile strength was 500 ± 10 MPa. Since this value is close to the tensile strength of 450 MPa of a 12 μm thick copper foil obtained by low roughness rolling of tough pitch copper, it was found that the sheet has sufficient mechanical strength. Since this sheet has a high insulation resistance, it can also be used as a high-temperature refractory heat insulating material, a lining material for industrial furnaces such as heating furnaces and firing furnaces, and a sealing material. Also, in the same manner as in Example 1, the cut sheet was further cut into a size of 10 cm × 10 cm and overlapped on the surface of a copper sheet having a thickness of 1 mm and a size of 10 cm × 10 cm. Nine weights of 18 kg were placed on the surface of the overlapped sheets at equal intervals, and the sheets were joined together. Next, in accordance with the 180-degree peel test of JIS Z0237:2022 (Adhesive tape and adhesive sheet test method), the joining strength of the joint surface was examined at a peel rate of 300 mm / min. Since the peel force was 380 mN / 50 mm, sufficient joining strength was obtained. Therefore, the surface of the copper sheet is imparted with the insulating property, heat resistance, and heat insulating property of alumina, and the lubricity of the sheet. In this example, flat alumina powder produced by the hydrothermal synthesis method was used as the powder having a large aspect ratio in the form of plates, flakes, or scales. However, not limited to the flat alumina powder produced by the hydrothermal synthesis method, powders having a plate-like, flake-like, or scale-like shape made of various materials described in paragraph 30 can be used.

[0038] Example 5 In this example, a sheet having a structure in which the nonwoven fabric used in Example 3 is covered with a film formed by aggregations of three types of soft magnetic flat powders joined by friction pressure welding is continuously manufactured. The three types of soft magnetic flat powders have peak values of the imaginary part of the complex magnetic permeability at different frequencies. A magnetic sheet is continuously manufactured from aggregations of flat powders in which the flat surfaces of the three types of flat powders are randomly joined by frictional heat. Since the complex magnetic permeability of this magnetic sheet has characteristics in which the complex magnetic permeabilities of the three types of flat powders are added together, it becomes a magnetic sheet that absorbs electromagnetic waves over a wider frequency band or prevents interference from electromagnetic noise in a wide frequency band, as compared to using each of the three types of flat powders alone. The three types of alloy flat powders consist of flat powders of permalloy, flat powders of silicon steel with 3% silicon, and flat powders of electromagnetic stainless steel. Also, as the alcohol, 2-ethyl-1-hexanol having a viscosity of 9.8 mPa·s at 20°C and a boiling point of 185°C was used. Note that 2-ethyl-1-hexanol has a viscosity of 9.8 mPa·s at 20°C and is lower than the viscosity of isooctyl alcohol used in Example 4. On the other hand, the average particle diameters of the three types of soft magnetic flat powders used in Example 5 are 9 μm, 12 μm, and 14 μm, which are slightly larger than the average particle diameter of the alumina used in Example 4, but are small as the size of the powder. Also, since the flatness ratios of the three types of soft magnetic flat powders are large, the thicknesses of the three types of soft magnetic flat powders are thin and close to the thickness of the alumina. For this reason, the surface areas of the three types of soft magnetic flat powders are slightly larger than the surface area of the alumina powder. Therefore, 2-ethyl-1-hexanol, which has a lower viscosity than the isooctyl alcohol used in Example 4, is used as the alcohol constituting the suspension, and after vaporizing the 2-ethyl-1-hexanol, the three types of soft magnetic flat powders are stacked in a smaller number of sheets than the alumina powder used in Example 4. Note that since the three types of soft magnetic flat powders have a relatively high hardness with a Vickers hardness exceeding 200 HV, they are difficult to deform by compressive stress. Also, the powder used is flat powder as in Example 4, does not undergo plastic deformation, and further has an average thickness as thin as 0.37 μm. Therefore, even when the non-woven fabric with the flat powder attached is compressed, the flat powder does not break but only undergoes compressive deformation. On the other hand, although the thickness of the non-woven fabric is close to 0.25 mm, the gap between the two work rolls is as narrow as 0.065 mm. Therefore, the non-woven fabric in the manufactured sheet is crushed to a thickness close to 1 / 5 of the compressive stress. As the flat powder of permalloy, flat powder of permalloy consisting of 50% nickel (for example, a product developed by Sanyo Special Steel) was used. The flatness ratio of this flat powder is 38, and the average particle size is 14 μm. Therefore, the average thickness of the flat powder of permalloy is 0.37 μm. Also, the imaginary part of the complex permeability sharply rises from around 100 MHz, has a peak value of 8.8 at 3.3 GHz, decreases from around 4 GHz, and has a value of 3.5 at 10 GHz. Therefore, in the frequency band of 1 - 8 GHz, the imaginary part of the complex permeability has a value of 5 or more. In contrast, in the DC magnetic field, the initial relative permeability is 1×10 4 and the maximum relative permeability is 1.4×10 5 which is excellent. The flat powder made of silicon steel with 3% silicon (for example, a product developed by Sanyo Special Steel) has a flatness ratio of 34 and an average particle size of 9 μm. Therefore, the average thickness of the flat powder of 3% silicon steel is 0.26 μm. Also, the imaginary part of the complex permeability has the magnitude required in the high-frequency band, in contrast to permalloy. That is, it gradually increases from around 10 MHz, has a value of 2.3 at 1 GHz, intersects with the value of the imaginary part of the complex permeability of permalloy at 4.7 GHz, shows a peak value of 8.7 at 5.9 GHz, gradually decreases from around 6.3 GHz, still has a value of 5.9 at 10 GHz, and has a value of 3.7 at 12 GHz. Therefore, at 4.7 GHz and above, the value of the imaginary part of the complex permeability is larger than that of permalloy. The flat powder made of electromagnetic stainless steel with 7% chromium, 1% silicon, and 1.6% aluminum added to iron (for example, a product developed by Sanyo Special Steel) has a flatness ratio of 29 and an average particle size of 12 μm. Therefore, the average thickness of the flat powder of electromagnetic stainless steel is 0.41 μm. Also, the imaginary part of the complex permeability rapidly increases from around 10 MHz, has a value of 3.4 at 1 GHz, intersects with the imaginary part of the silicon steel with 3% silicon at 4.2 GHz, shows a peak value of 7.5 at 4.8 GHz, gradually decreases from around 5.5 GHz, still has a value of 4.8 at 10 GHz, and has a value of 3.1 at 12 GHz. Therefore, when using three types of flat powder consisting of flat powder of permalloy, flat powder of silicon steel with 3% silicon, and flat powder of electromagnetic stainless steel, the characteristics of the imaginary part of the complex permeability of the three types of flat powder are added, and the performance of absorbing electromagnetic noise in the intermediate frequency band from 2 to 8 GHz is improved. In particular, the performance of absorbing electromagnetic noise in the frequency band from 3.3 GHz, where the imaginary part of the complex permeability of permalloy shows a peak value, to 4.8 GHz, where the imaginary part of the complex permeability of silicon steel with 3% silicon shows a peak value, is improved. The container used was the container used in Example 1, and eight cylindrical rollers were installed in this container in the same manner as in Example 1. Furthermore, the 12-stage rolling mill used in Example 1 was used. However, since the soft magnetic flat powder does not plastically deform in the thickness direction, the gap between the two work rolls was set to a narrow gap of 0.065 mm, and the temperature was raised to 195 °C, which is 10 °C higher than the boiling point of 2-ethyl-1-hexanol. Next, a total of 10 kg of three types of fine flat powder consisting of flat powder of permalloy, flat powder of silicon steel with 3% silicon, and flat powder of electromagnetic stainless steel were weighed at a weight ratio of 10 to 9 to 20, and the three types of flat powder were mixed. Therefore, the arithmetic average thickness in the mixed powder composed of the three types of soft magnetic flat powder corresponds to 0.365 μm. This mixed powder and 12 kg of 2-ethyl-1-hexanol were filled into the container, and 2-methyl-1-hexanol was stirred to create a suspension in which the mixed powder was dispersed in 2-methyl-1-hexanol. Note that, in order to form a depth of 5.1 cm, six rollers from the second roller to the seventh roller are immersed in the suspension. Furthermore, the unwound fabric of the nonwoven fabric was set in the fabric pulling-out device, and the fabric was continuously pulled out from the nonwoven fabric at a speed corresponding to the peripheral speed of the eight cylindrical rollers. The pulled-out fabric was brought into contact with the first roller of the container, and further, the fabric was continuously brought into contact from the second roller to the seventh roller. After that, the fabric in contact with the seventh roller advances with its moving direction changed upward, and after being pulled up from the suspension, it comes into contact with the eighth roller. The fabric in contact with the eighth roller changes its moving direction by 90 degrees and moves in the direction of the gap between the two work rolls of the multi-stage rolling mill. The tip of the fabric immersed in the suspension is inserted into the gap between the two work rolls of the multi-stage rolling mill, and the fabric is compressed in the gap between the two work rolls. Further, the sheet discharged from the gap between the two work rolls was wound up by a winder rotating at the same speed as the rotational speed of the eight cylindrical rollers. The fabricated sheet was cut into lengths of 50 cm, and the cut sheets were analyzed. First, in the same manner as in Example 1, the cut sheets were observed and analyzed with an electron microscope. The thickness of the sheet was 0.065 mm. Next, secondary electron beams between 900 and 1000 volts of the reflected electron beam from the cross section were extracted and image processing was performed. Fine flat powders formed 21 to 22 layers and were stacked on top of and below the organic matter with a thickness of 0.05 mm, forming a joint with an average thickness of around 7.5 μm and covering the entire organic matter. Therefore, in the fabricated sheet, three types of flat soft magnetic powders formed 21 - 22 layers throughout the nonwoven fabric and overlapped. The overlapped soft magnetic powders were joined by friction pressure welding, and the aggregates of the soft magnetic powders joined by friction pressure welding covered the nonwoven fabric crushed by compressive stress. The thickness of this aggregate of soft magnetic powders is close to the thickness of the aggregate of soft magnetic powders before compression. That is, when the gap between flat surfaces is 10% of the thickness of the flat powder, the average thickness of the three types of flat soft magnetic powders that formed 21 - 22 layers and overlapped before compression is considered to be around 8 μm. Also, the thickness of the nonwoven fabric is close to 0.250 mm. Therefore, since the gap between the two work rolls of the multi - stage rolling mill is 0.065 mm, the thickness of the nonwoven fabric evenly covered with the aggregates of flat soft magnetic powders has a thickness nearly four times that. On the other hand, the result of Example 5 shows that the thickness of the nonwoven fabric crushed by compressive stress is 0.05 mm, and the thickness of the three types of flat soft magnetic powders joined by friction compression is around 7.5 μm. Therefore, the flat soft magnetic powders did not deform in the thickness direction and were joined by frictional heat between flat surfaces. As a result, a sheet with a thickness of 65 μm was formed. That is, when the nonwoven fabric evenly covered with the suspension approaches the gap between the two work rolls, 2 - methyl - 1 - hexanol vaporizes from the suspension, and then the nonwoven fabric evenly covered with the aggregates of three types of flat soft magnetic powders overlapped between flat surfaces is drawn into the gap between the two work rolls. Further, the surface layer of the aggregates of the three types of flat soft magnetic powders comes into contact with the two work rolls, and the surface layer of the aggregates of the three types of flat soft magnetic powders moves backward. Next, compressive stress is applied to the nonwoven fabric evenly covered with the aggregates of three types of flat soft magnetic powders overlapped between flat surfaces. First, the gap between flat surfaces in the aggregate of soft magnetic powders narrows, and the compressive deformation of the nonwoven fabric by the soft magnetic powders begins. Further, the joining between flat surfaces of the soft magnetic powders starts, and the compressive deformation of the nonwoven fabric by the soft magnetic powders proceeds. After that, when the joining between flat surfaces of the soft magnetic powders is completed and the compressive deformation of the nonwoven fabric is completed, all the soft magnetic powders are joined between flat surfaces, and the nonwoven fabric crushed by compressive stress is covered with the soft magnetic flat powders joined by friction pressure welding. As a result, a film with a thickness of around 65 μm was formed, which consists of aggregates of soft magnetic powders joined by friction compression, where the soft magnetic powders formed 21 - 22 layers and overlapped. Next, a part of the cut sheet was immersed in water. After that, the sheet was lifted out of the water and its surface was observed. As a result, several water droplets were present on the surface, and when the sheet was tilted diagonally, the water droplets easily fell. Therefore, the surface of the sheet has water repellency. After that, using a part of the cut sheet, the gas permeability was examined by a gas permeability measuring device (product of GTR Tech Co., Ltd.) based on the differential pressure type gas chromatography method of JIS K7126A method (differential pressure method). As a result, it was found that air does not permeate at atmospheric pressure. Therefore, the sheet has nonflammability and also has the heat resistance of iron. Furthermore, using a part of the cut sheet, the tensile strength was examined based on the copper foil test method for printed wiring boards JIS C6515. As a result, the tensile strength was 430 ± 10 MPa. Since this value is close to the tensile strength of 450 MPa of a copper foil with a thickness of 12 μm obtained by low roughness rolling of tough pitch copper, it was found that the sheet has sufficient mechanical strength as a sheet. Next, the performance of the created magnetic sheet to absorb electromagnetic noise was evaluated. A microstrip line with a length of 140 mm, a width of 30 mm, and a characteristic impedance adjusted to 50 Ω was fabricated on a substrate. The sheet was placed on the substrate such that the length direction of the sheet was aligned with the length direction of the microstrip line and their centers coincided, making it a sheet for absorbing noise. After that, S parameters were measured using a network analyzer (product N5230A of Agilent Technologies Co., Ltd.) connected to the microstrip line. Note that the S parameter S due to reflection 11 and the S parameter S due to transmission 12 From these, according to the following formula 1, the transmission loss in the microstrip line becomes the absorption amount of electromagnetic waves. (Formula 1) Reflection amount (dB) = 20 log|S 11 | Transmission amount (dB) = 20 log|S 12 | Absorption amount (%) = (1 - |S 11 | 2 - |S 12 | 2 ) × 100 The absorption was 8% at 1 GHz, 10% at 3.3 GHz, 9% at 4.7 GHz, 10% at 5.9 GHz, and 8% at 10 GHz. As a result, the absorption was 8% or more in a wide frequency band from 1 to 10 GHz. Also, in the same manner as in Example 1, the cut sheet was further cut into a size of 10 cm × 10 cm, and overlaid on the surface of a plastic sheet having a thickness of 1 mm and a size of 10 cm × 10 cm. Nine weights of 9 kg were placed on the surface of the overlaid sheets at equal intervals, and the sheets were joined together. Next, in accordance with the 180-degree peel test of JIS Z0237:2022 (Adhesive tape and Adhesive sheet test method), the joining strength of the joint surface was examined at a peel rate of 300 mm / min. Since the peel force was 360 mN / 50 mm, sufficient joining strength was obtained. Therefore, the surface of the plastic sheet was imparted with the function of a magnetic sheet that absorbs electromagnetic waves over a wide frequency band or prevents electromagnetic noise interference in a wide frequency band. Note that the case of combining soft magnetic flat powders made of multiple types of alloys is not limited to Example 5. That is, when the flat powders are combined so that the imaginary part of the complex permeability has a constant value in a wide frequency band, the collection of flat powders in which the flat surfaces overlap and are joined shows the characteristics of the imaginary part of the complex permeability obtained by adding the characteristics of the imaginary part of the complex permeability of each flat powder. As a result, a sheet that absorbs electromagnetic noise can be realized in a wide frequency band.

Explanation of symbols

[0039] 1 Copper powder 2 Cut fabric

Claims

1. A method for continuously producing a sheet having a structure in which a woven fabric or nonwoven fabric is entirely covered with a coating formed of an aggregate of one type of powder made of any one of metals, alloys, metal oxides, and nitrides, each having a size of microns and joined by friction welding, comprises the steps of: First, in a container that is wider in width than the width of the sheet to be manufactured and has a length in which a plurality of the following cylindrical rollers can be provided, the container rotates at the same circumferential speed with a rotation time per revolution longer than 20 seconds. A plurality of cylindrical rollers having the same length equal to the width of the container and the same diameter are spaced apart from each other and provided parallel to the width of the container. The arrangement positions of the plurality of cylindrical rollers on the container are as follows: The first roller is installed at a position where the uppermost part corresponds to a height in contact with a fabric or non-woven fabric drawn from a roll of fabric or non-woven fabric used in the second step, and is installed at a position more than 1 cm away from one side surface forming the width of the container. The second roller is installed at a position farther from one side surface forming the width of the container by the size of the first roller compared to the installation position of the first roller, and is installed at a position more than 1 cm away from the bottom surface of the container. The last roller is installed at a position more than 1 cm away from the other side surface forming the width of the container and at the same height as the height at which the first roller is installed. The second-to-last roller is installed at a position farther from the other side surface forming the width of the container by the size of the last roller compared to the installation position of the last roller and at the same distance from the bottom surface of the container as the second roller. The remaining plurality of rollers are installed at the same distance from the bottom surface of the container as the second roller, between the second roller and the second-to-last roller, with a distance of not more than twice the diameter of the cylindrical roller between each roller, and the rollers are arranged at equal intervals. Next, for a collection of the powder made of one of the materials of metal, alloy, metal oxide, or nitride with a size in the micron range, which has a weight greater than the weight required for continuously manufacturing a sheet, and for an alcohol with a viscosity of 3 - 11 mPa·s at 20°C, the smaller the size of the powder, the more asymmetric the shape of the powder, and the higher the hardness of the powder, the higher the viscosity of the alcohol used. The alcohol is filled into the container in an amount that forms a volume in which all the rollers except the first roller and the last roller are immersed. The alcohol is stirred to create a suspension in which the collection of the powder is dispersed in the alcohol.A first step of immersing all of the remaining rollers among the plurality of cylindrical rollers, excluding the first roller and the last roller, in the suspension; A roll of fabric or non-woven fabric having the width of the sheet to be manufactured is set on a pulling device for the roll, and the fabric or non-woven fabric is continuously pulled out from the roll at a speed corresponding to the peripheral speed of the plurality of cylindrical rollers in the first step. Thereafter, the pulled-out fabric or the pulled-out non-woven fabric contacts the uppermost part of the first roller, and a side surface close to 1 / 4 of the first roller contacts the first roller and moves together with the first roller. Thereafter, the moving direction is changed downward and the fabric or non-woven fabric moves and is immersed in the suspension. Further, since the rotation direction of the second roller in contact with the fabric or non-woven fabric is opposite to the rotation direction of the first roller, the fabric or non-woven fabric in contact with the second roller contacts a side surface close to 1 / 4 of the second roller and moves together with the second roller. Thereafter, the moving direction is changed in a direction parallel to the bottom surface of the container and the fabric or non-woven fabric moves and sequentially contacts a plurality of rollers excluding the first roller, the second roller, and the last roller. Since the rotation directions of the plurality of rollers are the same as the rotation direction of the second roller, the fabric or non-woven fabric sequentially contacting the plurality of rollers advances in the suspension without changing the moving direction and contacts the second last roller. Since the rotation direction of the second last roller in contact with the fabric or non-woven fabric is the same as the rotation direction of the second roller, the fabric or non-woven fabric in contact with the second last roller contacts a side surface close to 1 / 4 of the second last roller and moves together with the second last roller. Thereafter, the moving direction is changed upward and the fabric or non-woven fabric advances. After being pulled up from the suspension, the fabric or non-woven fabric contacts the last roller. Since the rotation direction of the last roller is opposite to the rotation direction of the second last roller, the fabric or non-woven fabric in contact with the last roller contacts a side surface close to 1 / 4 of the last roller and moves together with the last roller. Thereafter, the moving direction is changed in the direction of the gap between the two work rolls constituting the multi-stage rolling mill used in the third step and the fabric or non-woven fabric moves. Such a series of treatments for the fabric or non-woven fabric starts from the scene where the fabric or non-woven fabric pulled out from the roll contacts the first roller.The process up to the scene where the fabric or the non-woven fabric contacts the last roller and changes its moving direction in the direction of the gap between the two work rolls constituting the multi-stage rolling machine is carried out as a continuous process on the fabric or the non-woven fabric, which is the second step. First, two work rolls constituting a multi-stage rolling mill have the following five characteristics: First, they have the same width wider than the width of the sheet to be manufactured. Second, they have the same diameter smaller than 1 / 10 of the width of the sheet. Third, a gap is set as the thickness of the sheet to be created. Fourth, they rotate in opposite directions at the same peripheral speed as the peripheral speed at which the plurality of rollers in the first step rotate. Fifth, they are heated to a temperature 10°C higher than the boiling point of the alcohol constituting the suspension in the first step. Then, a multi-stage rolling mill having these two work rolls is prepared. Next, the tip of the fabric or the non-woven fabric that has completed the treatment in the second step is inserted into the gap between the two work rolls. As a result, the tip of the fabric or the non-woven fabric is drawn into the gap between the two work rolls, and the fabric or the non-woven fabric continuously receives a compressive stress corresponding to the size of the gap between the two work rolls. At this time, first, alcohol vaporizes from the suspension evenly adhering to the fabric or the non-woven fabric, and the powder constituting the suspension overlaps and precipitates on the fabric or the non-woven fabric, and the fabric or the non-woven fabric is covered with the accumulation of the powder. Next, compressive stress begins to be applied to the accumulation of the overlapping and precipitated powder and the fabric or the non-woven fabric. First, the surface layer of the accumulation of the powder collapses. The surface layer of the accumulation of the powder precipitated at the end of the fabric or the non-woven fabric is such that the accumulation of the powder constituting the surface layer moves to the end and overlaps at the end, and the surface layer of the accumulation of the powder precipitated other than the end moves to the rear side of the gap between the two work rolls. Next, compressive stress is applied to the accumulation of the powder and the fabric or the non-woven fabric. The accumulation of the powder is compressed, and the fabric or the non-woven fabric is compressed and deformed. Further, it breaks due to the shear stress applied by the contacting powder, and the fabric or the non-woven fabric is divided. Furthermore, the powder moves to the broken part of the fabric or the non-woven fabric, the voids of the fabric, or the voids of the non-woven fabric, and the divided fabric or the divided non-woven fabric is covered with the accumulation of the powder. Furthermore, compressive stress is applied to the accumulation of the powder, and the accumulation of the powder covering the entire divided fabric or the divided non-woven fabric is joined by frictional pressure at all contact parts where adjacent powders contact each other.The aggregate of the powders joined by the friction welding is joined to the divided fabric or the divided nonwoven fabric by friction welding to cover the entire divided fabric or the divided nonwoven fabric. Further, the aggregate of the overlapping powders is joined by friction welding at all contact portions where the powders contact each other. The aggregate of the powders joined by the friction welding is joined by friction welding to the aggregate of the powders joined by friction welding to cover the entire divided fabric or the divided nonwoven fabric. As a result, the entire divided fabric or the divided nonwoven fabric is covered with a film made of the aggregate of the powders joined by the friction welding. From the phenomenon of vaporization of the alcohol, the phenomenon until the entire divided fabric or the divided nonwoven fabric is covered with a film made of the aggregate of the powders joined by the friction welding occurs continuously in the aggregate of the powders sandwiched between the gaps of the two work rolls and the fabric or the nonwoven fabric. As a result, a sheet having a structure in which the entire divided fabric or the divided nonwoven fabric is covered with the film is discharged from the gap between the two work rolls, and a third step of winding the discharged sheet with a winding device that rotates at the same speed as the rotational speed of the two work rolls is included. A method of continuously carrying out all of these three steps is a method of continuously producing a sheet having a configuration in which a woven fabric or nonwoven fabric is entirely covered with a coating formed by an aggregate of one type of powder made of one of the following materials: metal, alloy, metal oxide or nitride, each of which has a micron-sized size and is joined by friction welding.

2. A method for cutting the sheet produced by the method according to claim 1 into a predetermined shape and bonding the cut sheet to a predetermined position on the surface of a substrate or a part, comprising the steps of:

13. A method for continuously producing a sheet by the method described in claim 1, cutting the sheet into a predetermined shape, overlapping the cut sheet at a predetermined position on the surface of a substrate or a part, and evenly compressing the entire surface of the cut sheet, whereby the convex portions of the unevenness on the surface of the cut sheet come into contact with the surface of the substrate or the part on which the cut sheet is overlapped, and further, frictional heat is generated at the contact portion, and the frictional heat bonds the contact portions together, and the cut sheet is bonded to the predetermined position on the surface of the substrate or the part. This is a method for cutting a sheet produced by the method described in claim 1 into a predetermined shape and bonding the cut sheet to the predetermined position on the surface of the substrate or the part.

3. A method for continuously producing a sheet having a structure in which a woven fabric or nonwoven fabric is entirely covered with a coating formed by an aggregate of powder particles bonded by friction welding according to claim 1, comprising the steps of: The powder described in claim 1 is a powder having a spherical, granular or lump shape, and the method of using the powder as the powder described in claim 1 and continuously carrying out all of the three steps described in claim 1 in order is a method of continuously producing a sheet having a configuration in which a cloth or nonwoven fabric is entirely covered with a coating formed by an aggregate of powder joined by friction welding as described in claim 1.

4. The powder having a spherical, granular or agglomerated shape according to claim 3 is copper powder, tin powder, copper-tin alloy powder, tantalum powder, niobium powder, Fe-based alloy having a composition of Fe-17Cr-12Ni-Mo, Ni-based alloy having a composition of Ni-16Cr-16Mo-5Fe-4W, Co-based alloy powder having a composition of Co-29Cr-6Mo, alloy powder having a composition of Fe-49Co-2V, precipitation hardened martensitic stainless steel powder having a composition of SUS630, austenitic stainless steel powder having a composition of SUS316L, martensitic stainless steel powder having a composition of SUS420J2, or low-oxygen titanium powder, all of which are produced by a gas atomization method; Or, Copper powder or silver powder produced by water atomization method, Any one of these 15 types of powder is the powder having a spherical, granular or lump shape as described in claim 3.

5. A method for continuously producing a sheet having a structure in which a woven fabric or nonwoven fabric is entirely covered with a coating formed by an aggregate of powder particles bonded by friction welding according to claim 1, comprising the steps of: The powder described in claim 1 is a powder that has a spongy shape but is not porous and that undergoes plastic deformation when compressed in the third step described in claim 1, and a method of using this powder as the powder described in claim 1 and continuously carrying out all of the treatments in the three steps described in claim 1 in order is a method of continuously producing a sheet consisting of a fabric or nonwoven fabric entirely covered with a coating formed by an aggregate of powder joined by friction welding as described in claim 1.

6. The powder having a sponge-like shape but not porous as described in claim 5 and undergoing plastic deformation when compressed in the third step as described in claim 1, The powder is either iron powder or bronze powder produced by a water atomization method, and one of these two types of powders has a spongy shape as described in claim 5 but is not porous, and is a powder that undergoes plastic deformation when compressed in the third step as described in claim 1.

7. A method for continuously producing a sheet having a structure in which a woven fabric or nonwoven fabric is entirely covered with a coating formed by an aggregate of powder particles bonded by friction welding according to claim 1, comprising the steps of: The powder described in claim 1 has a teardrop or spindle shape, and is a powder that undergoes plastic deformation when compressed in the third step described in claim 1. A method of using the powder as the powder described in claim 1 and sequentially and continuously performing all the processes of the three steps described in claim 1 is a manufacturing method for continuously manufacturing a sheet having a structure in which the entire surface of the fabric or non-woven fabric described in claim 1 is covered with a film formed by an aggregate of powders joined by friction pressure welding.

8. The powder having a teardrop or spindle shape described in claim 7 and undergoing plastic deformation when compressed in the third step described in claim 1 is aluminum powder produced by the gas atomization method, nickel powder produced by the water atomization method, Fe-3Si alloy powder, 47Ni-Fe alloy powder, 78Ni-4Mo-Fe alloy powder, or brass powder. Any one of these six types of powders is a powder having a teardrop or spindle shape described in claim 7 and undergoing plastic deformation when compressed in the third step described in claim 1.

9. A manufacturing method for continuously manufacturing a sheet having a structure in which the entire fabric or non-woven fabric is covered with a film formed by an aggregate of powders joined by friction pressure welding described in claim 1 is The powder described in claim 1 is a powder having a plate-like, flake-like, or scaly shape with a large aspect ratio of the powder. A method of using the powder as the powder described in claim 1 and sequentially and continuously performing all the processes of the three steps described in claim 1 is a manufacturing method for continuously manufacturing a sheet having a structure in which the entire surface of the fabric or non-woven fabric described in claim 1 is covered with a film formed by an aggregate of powders joined by friction pressure welding.

10. The powder having a plate-like, flake-like, or scaly shape with a large aspect ratio of the powder described in claim 9 is flake powder of a soft metal composed of gold powder, silver powder, copper powder, tin powder, zinc powder, or aluminum powder obtained by crushing a soft metal powder with a stamp mill, or Silicon steel powder with a silicon addition amount of less than 10% obtained by subjecting atomized soft magnetic powder or reduced soft magnetic powder to attritor treatment using a media agitation type mill, permalloy powder with a nickel addition amount of 50% or less, sendust powder with an aluminum addition amount of 1 / 2 or more of the silicon addition amount, or electromagnetic stainless steel powder with an aluminum addition amount of less than 2%, which is a flat powder of a soft magnetic alloy composed of or Aluminum oxide powder produced by hydrothermal synthesis of aluminum hydroxide, mica powder produced by finely pulverizing mica, glass flake powder produced by crushing hollow-expanded molten glass, or hematite powder precipitated by hydrothermally treating yellow iron oxide in an alkaline aqueous solution, which is a flat powder of a metal oxide composed of or Hexagonal boron nitride powder produced by pulverizing massive boron nitride, Any one of these 15 types of powders is a powder having a plate-like, flake-like, or scaly shape with a large aspect ratio of the powder described in claim 9.

11. A manufacturing method for continuously manufacturing a soft magnetic sheet that absorbs electromagnetic waves or a soft magnetic sheet that prevents electromagnetic noise interference, using the flat powders of the four types of soft magnetic alloys described in claim 10, is Among the flat powders composed of the four types of soft magnetic alloys described in claim 10, select a plurality of types of soft magnetic flat powders having a magnitude of the imaginary part of the complex permeability that is above a certain value in different frequency bands from the flat powders composed of the four types of soft magnetic alloys. Mix the selected flat powders composed of a plurality of types of soft magnetic alloys at a predetermined ratio. Use the collection of the mixed flat powders composed of a plurality of types of soft magnetic alloys as the powder described in claim 1, and perform all the processes of the three processes described in claim 1 in sequence continuously. This is a manufacturing method for continuously manufacturing a soft magnetic sheet that absorbs electromagnetic waves or a soft magnetic sheet that prevents electromagnetic noise interference.

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