JP2000080591A - Metal fiber sheet, metal fiber sheet laminate, and method for manufacturing metal fiber sheet - Google Patents

Abstract

(57) [Problem] To provide a metal fiber sheet having a sheet strength that is easy to handle before a sintering step and a luster unique to a metal even after sintering. A papermaking apparatus 1 for papermaking a metal fiber sheet S2 by a wet papermaking method includes: a papermaking step 20 for papermaking a raw material slurry S1 including one or more metal fibers; The fiber entanglement process 30 is performed by jetting high-pressure jet water streams W1 and W2 from the shower nozzle 31 to the metal fiber sheet S2. Since the fiber entanglement process step 30 is included, the metal fiber sheet S
The two metal fibers are entangled with each other, and the sheet strength of the metal fiber sheet S2 after papermaking can be ensured without adding an organic binder or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal fiber sheet obtained by making a slurry containing one or more kinds of metal fibers by wet papermaking.

[0002]

2. Description of the Related Art Conventionally, as a sheet-like material having fine pores composed of 100% metal, a woven fabric such as a wire mesh, a dry web, a wet web, a powder sintered body, and a nonwoven fabric are plated, and then the nonwoven fabric is degreased. Many things, such as a metal sheet obtained by using it, are used. Further, a sheet-like material composed of metal fibers, metal powders and the like is generally formed into a sheet by sintering in a vacuum or a non-oxidizing atmosphere to fuse the overlapping portions of the metal fibers. .

[0003] Among such sheet-like materials, a metal fiber sheet obtained by making a slurry containing metal fibers by papermaking by a wet papermaking method is known. According to the metal fiber sheet obtained by the wet papermaking method, the metal fiber sheet can be formed by randomly orienting the metal fibers from the characteristics of the manufacturing method called the papermaking method, and the sheet formation is uniform and thin and dense. It can be a metal fiber sheet, and can be used in many fields such as a filter material, a buffer material, an electromagnetic wave shielding material, and an electrode material.

[0004] The above-mentioned conventional method for producing a metal fiber sheet is to form a slurry in which metal fibers are dispersed in water together with organic binder fibers, make this slurry on a net, dehydrate, press and heat dry. Into a sheet,
Thereafter, the organic binder fiber is decomposed and removed by heating in a vacuum or in a non-oxidizing atmosphere, and the portion where the metal fibers overlap with each other is sintered at a temperature equal to or lower than the melting point of the metal.
% Sheet.

[0005]

However, such a conventional method for manufacturing a metal fiber sheet has the following problems. That is, in the metal fiber sheet obtained by the above-mentioned wet papermaking method, the sheet is formed by spontaneous dehydration or suction dehydration on a net, and when a slurry in which metal fibers are dispersed is formed on the net, the metal The problem is that the fibers are only laminated on the net and there is little entanglement between the metal fibers, and the sheet strength of the metal fibers alone is low, making it extremely difficult to process the papermaking stage and handling the paper-made metal fiber sheet. There is.

[0006] For this reason, usually, a long fiber organic binder fiber is added to a slurry in which metal fibers are dispersed, and the entanglement of the organic binder fiber is used to ensure easy-to-handle sheet strength, or a relatively low temperature. In the drying step after papermaking, it is necessary to secure the sheet strength so that the organic binder is melted and the metal fibers are joined to each other to facilitate handling. In any case, in the production of the metal fiber sheet by the conventional wet papermaking method, it has been indispensable to add an organic binder fiber or an organic binder during the production process.

In the sintering step of the metal fiber sheet containing such an organic binder, the organic binder and the like contained therein are thermally decomposed when the temperature in the sintering furnace reaches about 400 ° C., and the temperature is further increased. This is to sinter the overlapping portions of the metal fibers at a temperature lower than the melting point of the fibers. However, the decomposition gas such as the organic binder generated in the sintering step is sequentially degassed out of the furnace in the temperature raising step, but cannot be completely degassed at present. Therefore, decomposition gases such as organic binders remain in the sintering furnace and become impurities, which deteriorate the furnace atmosphere, become carbides, contaminate the walls of the furnace, and adhere to metal fiber sheets. A problem will occur and sinterability will be impaired.

As a method of removing as much as possible the decomposition gas of the organic binder which inhibits the sinterability outside the furnace, for example,
In the sintering in the non-oxidizing atmosphere, a method of increasing the supply amount of the gas constituting the non-oxidizing atmosphere, a method of supplying the gas, and changing a structure in the furnace are conceivable. Further, for example, in sintering in a vacuum, a method of removing a decomposition gas by increasing the degree of vacuum may be considered. However, in these methods, it is difficult to completely remove the decomposition gas, and in fact, good sinterability is not achieved, and the above-mentioned improvement means also increases the production cost. Having. Therefore, in the sintering step, a metal fiber sheet that does not contain an organic binder that inhibits sinterability is required, but as described above, an organic binder is indispensable due to the problem of strength.

An object of the present invention is to solve the above-mentioned problems, to provide a metal fiber sheet and a metal fiber which have a sheet strength which is easy to handle before the sintering step and which have a gloss characteristic of a metal even after the sintering. It is to provide a sheet laminate and a method for producing a metal fiber sheet.

[0010]

Means for Solving the Problems The metal fiber sheet according to the present invention is a metal fiber sheet obtained by making a slurry comprising one or more kinds of metal fibers by wet papermaking. The metal fibers are entangled with each other. Here, the above-mentioned metal fiber refers to a fiber made of a metal material such as stainless steel, aluminum, brass, copper, titanium, nickel, gold, platinum, lead, and the like. Alternatively, two or more types of metal fibers may be mixed to make paper. Further, the entanglement between the metal fibers can be achieved by performing a fiber entanglement treatment on a sheet formed on the mesh in the papermaking process, for example, on the surface of the metal fiber sheet containing an appropriate amount of moisture on the mesh. It can be performed by injecting a high-pressure jet water stream.

That is, in the conventional wet papermaking method of a metal fiber sheet, a sheet is formed by laminating metal fibers dispersed in water by spontaneous dewatering or suction dewatering on a wire mesh. The metal fibers of the obtained sheet are merely laminated so as to intersect irregularly in the plane direction, and very few fibers are oriented in the sheet thickness direction (Z-axis direction). Since there is almost no entanglement, sheet strength cannot be obtained. On the other hand, the metal fiber sheet according to the present invention is characterized by including a fiber entanglement treatment step of entanglement of the metal fibers with each other. For example, by jetting a high-pressure jet stream in the Z-axis direction of a sheet onto a sheet composed of metal fibers that intersect irregularly in the plane direction by wet papermaking, the metal fiber in the portion where the high-pressure jet stream is jetted is Z It is oriented in the axial direction. This Z
The metal fibers oriented in the axial direction are entangled between the metal fibers oriented irregularly in the plane direction, and the respective fibers are three-dimensionally entangled with each other, that is, physical strength can be obtained by entanglement. .

According to the present invention, since the metal fibers constituting the metal fiber sheet are entangled with each other, the sheet strength before the sintering step can be reduced without adding the above-mentioned organic binder fiber or organic binder. Can be secured,
The handling of the metal fiber sheet before the sintering step is facilitated. In addition, according to such a metal fiber sheet, since an organic binder or the like is not added, in the sintering step of the metal fiber sheet, the decomposition gas such as the organic binder does not become an obstacle, and the sheet surface has a whiteness of 30 or more. Thus, it is possible to obtain a metal fiber sheet having a gloss characteristic of a metal having a color difference of 50 or more. Furthermore, since the sheet strength after the wet papermaking process can be sufficiently ensured, a sheet of 100% metal fibers can be provided without sintering, and the metal fibers are physically entangled with each other. It is possible to further improve the sheet strength of the metal fiber sheet after sintering.

In the above, it is preferable that the above-mentioned metal fibers have a fiber diameter of 1 μm to 50 μm, preferably 8 μm to 20 μm, and an aspect ratio of 500 to 3000, and more preferably an aspect ratio of 500 to 3000. It is good to adopt the thing whose ratio is 1000-2000. That is, such a metal fiber is suitable for entanglement of the metal fibers with each other by a high-pressure jet water flow, and by entanglement of such metal fibers, a metal fiber sheet with little surface fuzz is formed. It becomes possible. When a slurry containing long-fiber metal fibers is produced, the dispersibility of the metal fibers in water may deteriorate. Therefore, a polymer aqueous solution such as polyvinylpyrrolidone, polyvinyl alcohol, or CMC, which has a viscous action, may be used. May be added in small amounts.

Further, the metal fiber sheet laminate according to the present invention is a metal fiber sheet laminate obtained by laminating the above-mentioned metal fiber sheets and, if necessary, sintering the metal fiber sheets. In this method, the metal fiber sheets have a striped formation extending along the sheet flow direction in the method, and the metal fiber sheets are stacked so as to cross each other. Here, the striped formation of the metal fiber sheet is formed mainly in a fiber entanglement process step of entanglement of the metal fibers, for example, a plurality of nozzle holes are formed along a direction orthogonal to the flow direction of the sheet. It can be formed by a multi-hole nozzle or the like.

According to the present invention, since the metal fiber sheet laminate is laminated so that the striped formations of the metal fiber sheet cross each other, the tensile strength of the metal fiber sheet laminate is reduced in the direction. Irrespective of this, it can be made uniform. In addition, since the above-described metal fiber sheets in which the metal fibers are entangled are laminated, the metal fiber sheet laminate in which the metal fibers are entangled uniformly in the thickness direction can be formed.

In the method for producing a metal fiber sheet according to the present invention, when a slurry comprising one or more metal fibers is formed into a sheet by a wet papermaking method, the slurry contains water on the net. And a fiber entanglement treatment step of entanglement of the metal fibers forming the elastic sheet with each other. Here, as the fiber entanglement treatment step, for example, it is preferable to adopt a fiber entanglement treatment step of jetting a high-pressure jet water stream onto the metal fiber sheet surface after papermaking, and specifically, in a direction orthogonal to the sheet flow direction. By arranging a plurality of nozzles and simultaneously jetting a high-pressure jet water stream from the plurality of nozzles, it is possible to entangle the metal fibers over the entire sheet. Further, as the papermaking method, for example, various methods such as fourdrinier papermaking, circular net papermaking, inclined wire papermaking, etc. can be adopted.

According to the present invention, since the fiber entanglement process is provided, the metal fibers can be entangled with each other to secure the sheet strength of the metal fiber sheet.
The handling of the metal fiber sheet during and after the papermaking process is facilitated, and the productivity of the metal fiber sheet is significantly improved. In addition, if the fiber entanglement process is performed by injecting a high-pressure jet water stream, the metal fibers can be entangled simply by arranging a plurality of nozzles in a direction orthogonal to the flow direction of the sheet after papermaking. Therefore, the production of the above-mentioned metal fiber sheet is facilitated, and the production equipment is simplified.

In the above-described high-pressure jet water stream, a plurality of nozzle holes arranged in a direction orthogonal to the sheet flow direction in the papermaking process are arranged in two or more stages,
It is preferable that the high-pressure jet water jets jetted from the plurality of nozzles have a gradually increasing water pressure from the preceding nozzle to the subsequent nozzle. That is, since the high-pressure jet water stream is jetted from the plurality of nozzles in a stepwise manner, it is possible to perform the fiber entanglement process evenly over the entire metal fiber sheet. Also, if the water pressure of the high-pressure jet stream is increased from the nozzle at the former stage toward the nozzle at the latter stage, the entanglement of the metal fibers is gradually performed, so that the metal fibers are entangled with the papermaking net and cannot be peeled off, It is also possible to prevent the metal fibers from being blown off by the high-pressure jet water flow.

Further, the method for producing a metal fiber sheet includes a sintering step of sintering the obtained metal fiber sheet at a temperature equal to or lower than the melting point of the metal fiber in a vacuum or a non-oxidizing atmosphere after the above-mentioned wet papermaking step. It is preferable to include it. That is, if the sintering step is performed after the above-described wet papermaking step, the fiber entanglement treatment is performed, and it is not necessary to add an organic binder or the like to the metal fiber sheet. It is possible to produce a metal fiber sheet having a glossy surface peculiar to a metal without hindering the process. Further, since the metal fibers are entangled, the strength of the metal fiber sheet after sintering can be further improved.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a papermaking apparatus 1 for producing a metal fiber sheet according to an embodiment of the present invention. The papermaking apparatus 1 is a fourdrinier papermaking apparatus,
It is configured to include a raw material supply unit 10 that supplies the raw material slurry S1, a papermaking unit 20, and a fiber entanglement processing unit 30. The raw material supply unit 10 includes a head box 11 for supplying a raw material slurry S1 on a wire 21 described later, and a supply pipe 12 for supplying the raw material slurry S1 adjusted in the previous process to the head box 11. . Although not shown in FIG. 1, a slit corresponding to the width of the wire 21 is formed at the bottom of the head box 11, so that the raw slurry S1 can be supplied onto the wire 21.

The papermaking section 20 is provided with an endless orbital wire 21 for removing water from the raw material slurry S1 and making paper.
And a turn roll 22, a coach roll 23, and a guide roll 24 for supporting the wire 21;
25, table roll 26, which supports
And a suction box 27.
Then, the coach roll 23 is rotated by driving means (not shown) or the like, and accordingly, the wire 21 moves in an endless track along the above-described roll and box.

The fiber entanglement unit 30 is disposed above the above-mentioned suction box 27 and has a shower nozzle 31 having a nozzle hole directed to the upper surface of the wire 21, and a high-pressure pump for supplying high-pressure fresh water to the shower nozzle 31. 32
It is comprised including. Two shower nozzles 31 are arranged along the sending direction of the metal fiber sheet made by the paper making section 20, and are configured to be able to process the entanglement of the metal fiber sheet in two stages.

Here, the shower nozzle 3
The moisture of the metal fiber sheet S2 sent to the portion 1 is 30
% To 70%. That is, in a dry state in which the water content of the metal fiber sheet S2 is less than 30%, if the high-pressure jet water streams W1 and W2 are jetted from the shower nozzle 31 to the metal fiber sheet S2, the metal fibers are easily scattered by the water pressure. . Conversely, if the water content is large, the formation of the portion where the high-pressure jet water flows W1 and W2 do not hit is likely to be lost, and in any case, uniform sheet formation may be impaired.

Each shower nozzle 31 has a nozzle diameter of 0.2
mm or less, preferably 0.1 mm or less,
Nozzle spacing in the direction perpendicular to the flow direction
1.0mm perforated nozzle with shower nozzle
Le 31 has a water pressure of 5 kg / cm ^Two~ 100kg / cm^TwoHigh pressure jet
Inject two streams of water, as shown in FIG.
When disposing the shower nozzle 31 in multiple stages,
The nozzle 31 is at the same pressure as the shower nozzle 31 at the previous stage.
Inject high-pressure jet water to be equal to or greater than
It is configured to be.

Here, the diameter of the shower nozzle 31, the interval,
The water pressure and the like are appropriately set according to the material, thickness, length, and the like of the metal fiber, the papermaking speed, the amount of moisture, and the like, but are preferably in the above range. This is because, for example, if the nozzle diameter is too large, there is a possibility that a pinhole may be generated or good confounding may not be formed. Further, if the interval between the nozzles is too wide or the water pressure is too low, entanglement is insufficient and good sheet strength cannot be obtained, and conversely, if the interval between the nozzles is too narrow or the water pressure is too high, it is formed. This is because there is a problem that the uniformity of the sheet, that is, the so-called formation deteriorates. Although not shown in FIG. 1, this papermaking apparatus 1
Is provided with a known press section and a drying section at the subsequent stage of the fiber entanglement processing section 30.

In such a papermaking apparatus 1, for example, a metal fiber sheet is manufactured as follows. The raw material slurry S1 was prepared by dispersing 100 parts by weight of stainless fiber having a fiber diameter of 8 μm and a fiber length of 12 mm in water at room temperature with a reciprocating rotary stirrer for 10 minutes so that the concentration became 0.05%. It is carried out by adding 5 parts by weight of polyacrylamide dissolved in 0.1%. The prepared raw material slurry S1 is supplied to the head box 11
Is supplied onto the wire 21 from the slit. At this time, the moving speed of the wire 21 and the interval between the slits of the head box 11 are adjusted so that the weight of the metal fiber sheet becomes 300 g / m ² .

The raw material slurry S 1 on the wire 21 is
While moving on the foil 25 and the table roll 26, the water is discharged under the net of the wire 21 and is made into a metal fiber sheet S2. At a stage where the water content of the metal fiber sheet S2 has been removed to some extent, a high-pressure jet stream W1 having a water pressure of 30 kg / cm ² is jetted onto the surface of the metal fiber sheet S2 by the shower nozzle 31 in the preceding stage.
A high-pressure jet water stream W2 having a water pressure of 50 kg / cm ² is jetted by the shower nozzle 31 at the subsequent stage, and the fiber entanglement treatment of the metal fiber sheet S2 is performed. In this fiber entanglement treatment,
The high-pressure jet water streams W1 and W2 are jetted at a feed speed of the metal fiber sheet S2 of 5 m / min.

After that, the metal fiber sheet S2 is compressed in a press section to remove moisture, and further dried at 100 ° C. in a drying section. After drying by the drying unit, the metal fiber sheet is cut into a desired size and sintered in a vacuum sintering furnace having a degree of vacuum of 10 ⁻⁴ Torr at a sintering temperature of 1120 ° C. and a holding time of 30 minutes. The sheet is completed. The surface of the sintered metal fiber sheet has a luster (brightness) peculiar to a metal, and a stripe-like formation formed by the above-described fiber entanglement process is slightly recognized. The pitch is the same as the shower nozzle 3 described above.
It is defined by one nozzle hole interval.

According to the above-described embodiment, the following effects can be obtained. That is, since the stainless steel fibers constituting the metal fiber sheet S2 are entangled with each other by the fiber entanglement process in the fiber entanglement processing section 30, even after adding the organic binder fiber, the organic binder, and the like to the raw material slurry S1, the paper after the papermaking is performed. Sheet strength can be ensured, and handling of the metal fiber sheet S2 such as cutting before the sintering step can be easily performed.

The fiber entanglement treatment of the metal fiber sheet S2 is performed by the high pressure jet water flows W1, W2 from the shower nozzle 31.
Since it is only necessary to spray, the fiber entanglement process can be simplified, and the production of the metal fiber sheet can be facilitated and the production equipment can be simplified. Further, the fiber entanglement processing unit 30
Since the fiber entanglement process is performed stepwise by the two shower nozzles 31, the fiber entanglement process can be performed uniformly over the entire metal fiber sheet S2.

Since the water pressure of the high-pressure jet water flow of the first-stage shower nozzle 31 is 30 kg / cm ² and the water pressure of the high-pressure jet water flow of the second shower nozzle 31 is 50 kg / cm ² , the water pressure gradually increases. Stainless steel fibers are gradually entangled with each other, so that it is possible to prevent the stainless fibers from being entangled with the wire 21 so that they cannot be peeled off, or the stainless fibers from being blown off by the high-pressure jet water flow.

Further, since the metal fiber sheet S2 thus obtained does not contain an organic binder or the like, it has a luster peculiar to a metal without a decomposition gas of the organic binder or the like in the sintering step. A metal fiber sheet can be obtained. Further, similarly, the sheet strength after the sintering step can be sufficiently ensured without adding an organic binder or the like, and since the stainless steel fibers are physically entangled by the fiber entanglement treatment, the sheet of the metal fiber sheet is similarly formed. Strength can be further improved.

Since the stainless steel fiber constituting the raw material slurry S1 has a fiber diameter of 8 μm and a fiber length of 12 mm (aspect ratio 1500), it is suitable for being entangled with each other by the fiber entanglement unit 30 and a metal fiber sheet. Since S2 is composed of such stainless steel fibers, a metal fiber sheet having a less fuzzy surface can be formed.

Note that the present invention is not limited to the above-described embodiment, but includes the following modifications. In the above-described embodiment, the metal fiber sheet S2 is formed from one type of stainless steel fiber. However, the present invention is not limited to this, and the metal fiber sheet may be formed from a plurality of types of metal fiber such as stainless steel fiber and aluminum fiber. In the above-described embodiment, the fiber entanglement processing unit 30 includes the shower nozzles 31 arranged in two stages in the flow direction of the metal fiber sheet S2.
The fiber entanglement processing unit may be configured to perform the fiber entanglement processing by the high-pressure jet water flow in one stage according to 1. Further, three or more shower nozzles 31 are arranged along the flow direction of the metal fiber sheet, The fiber entanglement treatment of the metal fiber sheet may be performed in three or more stages.

Further, in the above-described embodiment, the metal fiber sheet S2 after the papermaking is sintered in the sintering step as it is to form a thin leaf metal fiber sheet. The metal fiber sheet laminate may be sintered as required in a sintering step. In addition, when laminating the metal fiber sheets S2, it is preferable that the metal fiber sheets S2 are laminated so that the striped formation seen on the sheet surface, that is, the sheet flowing directions cross each other.

With this configuration of the metal fiber sheet laminate, the tensile strength of the metal fiber sheet laminate can be made uniform regardless of the direction. Further, since the metal fiber sheet laminate is formed by laminating the metal fiber sheets S2 in which metal fibers are entangled, it is possible to form a metal fiber sheet laminate in which metal fibers are entangled uniformly in the thickness direction, For example, it can be used as a sheet requiring uniform formation like a filter material. When a thin material is required, the sheet may be sintered after being subjected to pressure bonding after lamination.

In the above embodiment, the papermaking apparatus 1
Was a fourdrinier papermaking machine, but not limited to this.
Even if the present invention is applied to a round papermaking type papermaking apparatus and an inclined wire type papermaking apparatus, the same effects as in the above-described embodiment can be enjoyed. In the above-described embodiment, the sintering step is performed in a vacuum sintering furnace separated from the papermaking step. However, the sintering step is not limited to this, and may be performed in a reducing atmosphere such as hydrogen or an inert gas atmosphere such as argon. The sintering may be performed in a non-oxidizing atmosphere continuous sintering furnace that continuously performs sintering in a non-oxidizing atmosphere. In addition, specific structures, shapes, and the like at the time of carrying out the present invention may be other structures and the like as long as the object of the present invention can be achieved.

[0038]

EXAMPLES Next, the performance evaluation of the stainless steel fiber sheet manufactured by the method of the above-described embodiment was performed, and will be described below. <Example 1> The metal fiber sheet S2 obtained by the papermaking apparatus 1 according to the above-described embodiment was sintered in a vacuum sintering furnace having a degree of vacuum of 10 ^-4 Torr at a sintering temperature of 1120 ° C and a holding time of 30 minutes. To obtain a metal fiber sheet. <Example 2> The metal fiber sheet S2 obtained by the papermaking apparatus 1 according to the above embodiment was sintered in a continuous sintering furnace in a hydrogen atmosphere under the conditions of a sintering temperature of 1120 ° C and a holding time of 20 minutes. A fiber sheet was obtained.

Comparative Example 1 Fiber diameter 8 μm, fiber length 12 mm
100 parts by weight of stainless steel fiber and 10 parts by weight of polyvinyl alcohol fiber having a water dissolution temperature of 70 ° C. were dispersed in water at room temperature for 10 minutes with a reciprocating rotary stirrer to a concentration of 0.05%. 5% by weight of polyacrylamide dissolved in 0.1% was added to prepare a raw material slurry. This raw material slurry is weighed 300 g by wet papermaking method.
/ M ^2, and after dehydration, pressing, and heat drying, a sheet with a high content of stainless fibers was obtained. The obtained sheet in a vacuum furnace, after decomposing and removing the polyvinyl alcohol fibers and held 1 hour at 60 ° C., vacuum of 10 ^-4 the To
rr, sintering was performed at a sintering temperature of 1120 ° C. for a holding time of 30 minutes to obtain a metal fiber sheet.

Comparative Example 2 Fiber diameter 8 μm, fiber length 12 mm
100 parts by weight of stainless steel fiber
The mixture was dispersed with a reciprocating rotary stirrer for 10 minutes so that the concentration became 5%, and 5 parts by weight of polyacrylamide dissolved at a solid content of 0.1% was added to prepare a raw material slurry. This raw material slurry was made into a weight of 300 g / m ² by a wet papermaking method, and after dehydration, pressing and drying by heating, a metal fiber sheet was obtained.

With respect to Examples 1 and 2, and Comparative Examples 1 and 2, sheet handling properties after papermaking, sheet strength after sintering, and glitter on the sheet surface were evaluated. In addition, the sheet strength after sintering measures the tensile strength based on the method of JISP8113. Further, regarding the brilliancy of the sheet surface, the whiteness according to JISP8123 and JISZ8
The evaluation is based on the color difference according to 722. Table 1 shows Example 1
And 2, and the evaluation results of Comparative Examples 1 and 2.

[0042]

[Table 1]

In the metal fiber sheets after the paper making in Examples 1 and 2, the water flow jetted from the shower nozzle 31 of the paper making apparatus 1 causes entanglement between the stainless fibers, and there is no inter-fiber bonding by an organic binder or the like. In both cases, it can be seen that the sheet after papermaking has physical strength and good handleability. Also, since it does not contain organic binders, etc.
It can be seen that when the metal fiber sheets of Example 1 and Example 2 were sintered in a sintering furnace, a highly brilliant metal fiber sheet having a whiteness of 30 or more and a color difference of 50 or more was obtained.

On the other hand, since the sheet with a high blend of stainless fibers of Comparative Example 1 contains a polyvinyl alcohol binder, the sheet after papermaking has physical strength and good handling properties. Is sintered in a vacuum furnace, as compared with Examples 1 and 2.
It can be seen that the values of the whiteness and the color difference are small and the glitter is inferior. In addition, the metal fiber sheet after sintering of Comparative Example 1 had a clearly darker and darker color than the metal fiber sheets of Examples 1 and 2 even when visually observed.

The stainless fiber sheet of Comparative Example 2 did not contain an organic binder or the like and did not have any entanglement between the stainless fibers.
The sheet form could not be maintained during transfer or the like, and sintering did not occur due to poor handling properties. Furthermore, comparing the tensile strength of the sintered metal fiber sheet of Example 1 and Example 2 with the tensile strength of the sintered metal fiber sheet of Comparative Example 1, the metal fiber sheet of Example 1 and Example 2 was compared. It was confirmed that the tensile strength was high and the physical strength was improved due to the entanglement between the metal fibers.

[0046]

The metal fiber sheet of the present invention as described above,
According to the metal fiber sheet laminate and the method for manufacturing the metal fiber sheet, since the metal fibers are entangled with each other, the sheet strength before the sintering step is ensured without adding the organic binder fiber or the organic binder. Thus, the handling of the metal fiber sheet before the sintering step can be facilitated. In addition, since no organic binder or the like is added, in the sintering step of the metal fiber sheet, a decomposed gas such as the organic binder does not become an obstacle, and a metal fiber sheet whose surface has a gloss characteristic of a metal can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a papermaking apparatus according to an embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 20 papermaking section (papermaking process) 26 table roll 27 suction box 30 fiber entanglement processing section (fiber entanglement processing step) 31 shower nozzle 32 high-pressure pump S1 raw material slurry S2 metal fiber sheet W1, W2 high-pressure jet water flow

 ──────────────────────────────────────────────────続 き Continued on front page F-term (reference) 4F100 AB01A AB01B AB04A AB04B BA01 BA08 BA10A BA13 BA22 DG01A DG01B DG10A DG10B EC09A EC09B EC091 EJ481 EJ591 GB48 GB56 GB90 HB00A JA20A JK11 JL10A JA21A32 DA08 KA01 KA22 KA32 KA37 KA57 4L055 AF02 AJ01 AJ10 BE20 EA11 EA16 FA12 FA13 GA03 GA31 GA38

Claims (10)

[Claims] 1. A metal fiber sheet obtained by making a slurry containing one or more metal fibers by a wet papermaking method, wherein the metal fibers are entangled with each other. Characteristic metal fiber sheet. 2. The metal fiber sheet according to claim 1, wherein the metal fibers are entangled with each other by jetting a high-pressure jet of water onto the surface of the metal fiber sheet. 3. The metal fiber sheet according to claim 1, wherein the surface has a whiteness of 30 or more and a gloss of 50 or more in color difference. 4. The metal fiber sheet according to claim 1, wherein the metal fibers have a fiber diameter of 1 μm to 50 μm and an aspect ratio of 500 to 3000. Metal fiber sheet. 5. A metal fiber sheet laminate formed by laminating the metal fiber sheets according to any one of claims 1 to 4, wherein the metal fiber sheet is a sheet of the sheet in the wet papermaking method. A metal fiber sheet laminate having a stripe-shaped formation extending in the flow direction, wherein the formations of the metal fiber sheets are crossed and laminated. 6. The metal fiber forming a sheet containing moisture on a net when forming a sheet by a wet papermaking method using a slurry containing one or more kinds of metal fibers. A fiber entanglement treatment step of entanglement of the fibers with each other. 7. The method for manufacturing a metal fiber sheet according to claim 6, wherein the fiber entanglement treatment step is to jet a high-pressure jet stream on the surface of the sheet containing moisture on the net. A method for producing a metal fiber sheet. 8. The method for producing a metal fiber sheet according to claim 7, wherein the high-pressure jet water stream includes a plurality of nozzles arranged in a direction orthogonal to a flow direction of the sheet containing moisture on the net. A method for producing a metal fiber sheet, wherein the metal fiber sheet is arranged and jetted in stages or more. 9. The method for producing a metal fiber sheet according to claim 8, wherein the high-pressure jet water jet ejected from the plurality of nozzles comprises:
A method for manufacturing a metal fiber sheet, wherein the water pressure gradually increases from the nozzle at the front stage to the nozzle at the rear stage. 10. The method for producing a metal fiber sheet according to claim 6, wherein the metal fiber sheet is formed in a vacuum or in a non-oxidizing atmosphere after forming the metal fiber sheet by the wet papermaking method. A sintering step of sintering at a temperature equal to or lower than the melting point of the metal fiber.