JP2022090568A - Spinning device, fiber sheet production device, method for producing the same and method for producing fiber - Google Patents

Abstract

To provide a technique capable of performing spinning in such a manner that a resin is uniformly discharged from plural spinning ports and efficiently producing a high quality fiber sheet free from unevenness in weighing.SOLUTION: A spinning device 1 comprises: plural spinning ports 51 for discharging a raw material liquid; a constant rate pump 2 for feeding the raw material liquid to the spinning ports 51 via outflow side flow passages 42; and constant rate discharge parts 3 for connecting the constant rate pump 2 and the outflow side flow passages 42. The device comprises plural constant rate spinning structures 20 in which each constant rate discharge part 3 and each spinning port 51 corresponds one-to-one, and including the single spinning port 51 and the single constant rate discharge port 3 corresponding one-to-one and each outflow side flow passage 42 connecting both of them. In the plural constant rate spinning structures 20, the outflow side flow passages 42 are mutually independent.SELECTED DRAWING: Figure 2

Description

The present invention relates to a spinning device, a fiber sheet manufacturing device and a manufacturing method, and a fiber manufacturing method.

In spinning, a raw material liquid consisting of a viscous material obtained by heating and melting a spinning material such as a resin or dissolving it in a solvent and fluidizing it is continuously supplied to a predetermined storage portion such as a spinning head, and the storage portion is supplied with the raw material liquid. This is a technique for manufacturing yarn by discharging it from a connected spinneret. Depending on the form of the raw material liquid, there are melt spinning and solution spinning. Further, there are known spinning methods such as wet spinning, dry spinning, melt blown, and electric field spinning (electrostatic spinning), depending on the form in which the raw material liquid is fixed in the shape of a yarn after being discharged from the spinning port.

The melt blown method, the electrospinning method, and the like are used for manufacturing nanofibers, which are ultrafine fibers having a fiber diameter of nanosize. For example, if the constituent fibers of the non-woven fabric are such ultrafine fibers, various properties such as flexibility, liquid retention, concealing property, wiping property, separability, and insulating property are improved. Therefore, a non-woven fabric made of ultrafine fibers is desired. ing.

In a spinning device or a non-woven fabric manufacturing device using an electrospinning method, for the purpose of improving production efficiency, etc., a plurality of spinning ports for discharging raw material liquid are provided, and the raw materials are arranged in one row or multiple rows. A technique for producing a nonwoven fabric made of ultrafine fibers by discharging a liquid is known (see Patent Documents 1 to 3). For example, the non-woven fabric manufacturing apparatus described in Patent Document 1 supports a storage portion for a raw material liquid, a liquid feed pump, and a plurality of nozzles having a spun port at the tip, and supports and supplies the raw material liquid to each of the plurality of nozzles. A member is provided, and the raw material liquid in the storage portion is sent out toward the support supply member by the liquid feed pump, and the raw material liquid is distributed to each nozzle in the support supply member. The devices described in Patent Documents 2 and 3 are also generally configured in this way.

Japanese Unexamined Patent Publication No. 2008-30503 Japanese Unexamined Patent Publication No. 2011-89240 Japanese Unexamined Patent Publication No. 2019-60040

FIG. 9 shows a schematic configuration of a spinning device 90, which is an example of a conventional spinning device as described in Patent Documents 1 to 3. The spinning device 90 has a function in which a plurality of spinning devices 93 having a metering pump 91 and a nozzle having a spinning port 94 at the tip thereof are arranged on one surface, and the raw material liquid sent from the metering pump 91 is distributed to each spinning device 93. It is provided with a pair of liquid feeding blocks 92 and 92 having the above, and a flow path 96 on the outflow side of the raw material liquid connecting each of these parts. A storage unit 10 for storing the raw material liquid is connected to the metering pump 91 via an inflow side flow path 95, and the raw material liquid in the storage unit 10 is connected to the inflow side flow path 95 by driving the metering pump 91. It is designed to flow and be sent to the metering pump 91. A melt extruder 11 that supplies a molten resin as a raw material liquid is connected to the storage unit 10.

In the spinning device 90, the metering pump 91 and each liquid feed block 92 are connected by a single outflow side flow path 96, and the single outflow side flow path 96 branches in the liquid feed block 92 to provide a plurality of outflows. It becomes a side flow path 96 and is connected to a plurality of spinning ports 94 on a one-to-one basis. Therefore, in the spinning device 90, the raw material liquids used in the plurality of spinning devices 93 are collectively sent out from the metering pump 91 by a single outflow side flow path 96, and the plurality of outflow side flows branched in the middle of the delivery. It is distributed to each spinning device 93 by the path 96.

In the spinning device 90 having the above-described configuration, the discharge amount of the resin may be unintentionally non-uniform among the plurality of spinning ports 94. If the amount of resin discharged from a plurality of spinning ports is non-uniform, the fiber sheet made of fibers spun from the discharged resin may have a portion having a relatively large amount of the fiber and a portion having a relatively small amount of the fiber. There is unevenness in basis weight in a mixed state, and there is a possibility that the performance of the product using the fiber sheet may vary. Such unevenness in basis weight becomes particularly remarkable when a sheet having a small thickness such as a nanofiber sheet is manufactured, and in that case, more accuracy is easily required for the discharge amount of the resin.

An object of the present invention is to provide a technique capable of uniformly discharging a resin from a plurality of spinning ports to perform spinning, and efficiently producing a high-quality fiber sheet having no unevenness in basis weight.

The present invention includes a plurality of spinning ports that discharge a raw material liquid containing a resin, a metering pump that feeds the raw material liquid to the spinning port via an outflow side flow path, and the metering pump and the outflow side flow path. A single spinning device provided with a fixed-quantity discharge unit for connecting a plurality of the fixed-quantity discharge units, the fixed-quantity discharge unit and the spinning port having a one-to-one correspondence, and the one-to-one correspondence. It is provided with a plurality of fixed-quantity spinning structures including a spinning port, a single fixed-quantity discharge unit, and the outflow-side flow path connecting the two. It is a spinning device.

Further, the present invention is a fiber sheet manufacturing apparatus including the spinning apparatus of the present invention. Further, the present invention is a method for manufacturing a fiber sheet using the above-mentioned manufacturing apparatus of the present invention.

Further, in the present invention, a distribution step of distributing a raw material liquid containing a resin to a plurality of outflow side flow paths independent of each other and a plurality of the raw material liquids distributed to the plurality of outflow side flow paths are performed by using a pump. A liquid feeding step of quantitatively sending to a plurality of spinning ports corresponding to the outflow side flow path on a one-to-one basis, and a spinning step of discharging the raw material liquid from the plurality of spinning ports to form fibers. It is a method for producing a fiber, wherein the difference between the discharge weight of the resin per unit time of each of the plurality of spinning ports and the arithmetic average value thereof is within 10% of the arithmetic average value.

INDUSTRIAL APPLICABILITY According to the present invention, there is provided a technique capable of uniformly discharging a resin from a plurality of spinning ports to perform spinning, and efficiently producing a high-quality fiber sheet having no uneven basis weight.

FIG. 1 is a schematic perspective view of a main part of an embodiment of the spinning apparatus of the present invention. FIG. 2 is a schematic view of the spinning device shown in FIG. 1 when viewed from the direction indicated by reference numeral X in FIG. 1, and includes a schematic enlarged plan view of a part of the spinning device (quantitative discharge portion forming member). .. FIG. 3 is a schematic exploded perspective view of a liquid feeding block in the spinning apparatus shown in FIG. 1. FIG. 4 is a schematic view (side view) of the spinning apparatus shown in FIG. 1 when viewed from the direction indicated by reference numeral Y in FIG. FIG. 5 is a schematic front view of the liquid feeding block in the spinning apparatus shown in FIG. 1, and is a diagram illustrating the position of the metering pump. FIG. 6 is a schematic configuration diagram of another embodiment of the spinning apparatus of the present invention. FIG. 7 is a graph of the spinning amount (resin discharge weight) per unit time of each of the plurality of spinning ports in the spinning device of the embodiment. FIG. 8 is a graph of the spinning amount (resin discharge weight) per unit time of each of the plurality of spinning ports in the spinning device of the comparative example. FIG. 9 is a schematic configuration diagram of a conventional spinning apparatus.

Hereinafter, the present invention will be described based on the preferred embodiment thereof with reference to the drawings. In the description of the drawings below, the same or similar parts are designated by the same or similar reference numerals. The drawings are basically schematic, and the ratio of each dimension may differ from the actual one.

1 to 5 show a spinning device 1 which is an embodiment of the spinning device of the present invention. The spinning device 1 includes a plurality of spinning ports 51 for discharging a raw material liquid containing a resin, a metering pump 2 for feeding the raw material liquid to the spinning port 51 via an outflow side flow path 42, a metering pump 2 and an outflow side flow. It is provided with a fixed-quantity discharge unit 3 that connects to the road 42.

In the present embodiment, the spinning device 1 has a single metering pump 2, a metering discharge section forming member 30 having a metering discharge section 3, and a liquid feeding block having an inflow side flow path 41 and an outflow side flow path 42 inside. 4 and a plurality of (16 in the illustrated embodiment) spinning devices 5 including a spinning port 51, and the raw material liquid supplied from the outside to the metering pump 2 via the inflow side flow path 41 is discharged to the metering unit 3. The liquid is sent to each spinning device 5 via the outflow side flow path 42 and discharged from each spinning port 51 to manufacture fibers. In FIG. 2, from the viewpoint of easy understanding, the inflow side flow path 41 is indicated by a black arrow, and the outflow side flow path is indicated by a white arrow.

As the raw material liquid, a solution containing a resin (resin-containing solution) may be used, or a resin melt liquid may be used, which may be appropriately selected depending on the spinning method and the like. The resin-containing solution is prepared by dissolving or dispersing various resins that are raw materials for fibers in a solvent. The resin melt is prepared by heating various resins (thermoplastic resins), which are raw materials for fibers, to a temperature equal to or higher than the melting point.

As the resin contained in the raw material liquid, those that can be used for spinning can be used without particular limitation. Examples of the thermoplastic resin used in the resin melt include polyolefin-based thermoplastic resins such as polypropylene, polyethylene, and ethylene-propylene copolymer, polyethylene-based thermoplastic resins such as polyethylene terephthalate, polybutylene terephthalate, and polylactic acid, nylon and the like. Examples thereof include polyamide-based thermoplastic resins described above, and one of these can be used alone or in combination of two or more.

In this embodiment, a resin melt is used as the raw material liquid, and when the spinning device 1 is used, it is connected to the melt extruder 11 via the pipe 12 as shown in FIG. The melt extruder 11 is configured to melt the chips of the raw material resin and supply the raw material liquid as a raw material liquid to a predetermined supply destination (spinning device 1), and is provided with a raw material resin input unit, a cylinder with a built-in screw, and the like. There is. As the melt extruder 11, a known melt extruder 11 can be used without particular limitation.

The metering pump 2 may be any as long as it can repeatedly send a predetermined fixed amount of the raw material liquid, and known ones can be used without particular limitation. In the present embodiment, the metering pump 2 is a gear pump, and includes a motor 21 connected to a control device (not shown) and a pump unit 22 having a gear connected to the output shaft of the motor 21 and configured to be rotatable. The primary side of the pump unit 22 is connected to the melt extruder 11 which is the supply source of the raw material liquid via the inflow side flow path 41, and the secondary side of the pump unit 22 is spun through the outflow side flow path 42. It is connected to the spinneret 51 of the device 5. When the motor 21 is driven by a control device (not shown), the metering pump 2 rotates the gear of the pump unit 22 to pump the raw material liquid on the primary side to the secondary side.

As shown in an enlarged manner in FIG. 2, the fixed-quantity discharge unit 3 is a through hole that penetrates the plate-shaped fixed-quantity discharge unit forming member 30 in the thickness direction, and the fixed-quantity pump 2 and the outflow side flow path 42 are fixed-quantity discharge units. It communicates through 3. The fixed-quantity discharge unit forming member 30 is interspersed with the same number (16 in the illustrated embodiment) of the fixed-quantity discharge units 3 as the plurality of spinning ports 51 (spinning devices 5). The metering discharge portion forming member 30 is interposed and arranged between the metering pump 2 and the liquid feeding block 4 (the first block 43 described later). The fixed quantity discharge portion forming member 30 is made of a material (metal, plastic, etc.) having resistance to the raw material liquid. In the illustrated form, the fixed quantity discharge portion forming member 30 has a circular shape in a plan view, but the shape in a plan view of the fixed quantity discharge portion forming member 30 is not particularly limited.

The liquid feed block 4 supports each part of the spinning device 1 such as the metering pump 2, the metering discharge unit 3, and the spinning device 5. The flow paths 41 and 42 of the raw material liquid are formed inside the liquid feed block 4, and the liquid feed block 4 is made of a material (metal, plastic, etc.) having resistance to the raw material liquid. In the present embodiment, the liquid feeding block 4 has a rectangular parallelepiped shape as shown in FIG. 3, but the shape of the liquid feeding block 4 is not particularly limited.

In the present embodiment, the liquid feeding block 4 is configured to be separable into a plurality of parts. Specifically, as shown in FIG. 3, the liquid feed block 4 is configured to be divisible in the thickness direction, and the first block 43 to which the metering pump 2 is arranged and the second block 43 to which the spinning device 5 is arranged are arranged. Includes block 44 and. Both blocks 43 and 44 are detachably attached to each other by fasteners such as bolts and nuts and other known integrating means.

In the present embodiment, the outflow side flow path 42 includes a portion formed at the boundary between the first block 43 and the second block 44, as shown in FIGS. 2 and 3. More specifically, the liquid feed block 4 has the same number of outflow side flow paths 42 as the plurality of spinning ports 51 (spinning devices 5) (16 in the illustrated embodiment), and the plurality of outflow side flow paths 42 thereof. The portions extending in the direction orthogonal to the thickness direction (discharge direction of the raw material liquid) of the liquid feed block 4 in each are the portion formed on the facing surface of the first block 43 with the second block 44 and the portion of the second block 44. It is composed of a portion formed on a surface facing the first block 43, and by superimposing both blocks 43 and 44 at appropriate positions, both portions overlap to form an outflow side flow path 42. As shown in FIG. 3, the plurality of outflow side flow paths 42 formed at the boundary between the two blocks 43 and 44 and extending in the direction orthogonal to the discharge direction of the raw material liquid are arranged positions of the metering pump 2 (liquid feeding block 4). Radiates from the central part) when viewed from the discharge direction of the raw material liquid.

In the present embodiment, a plurality of spinning devices 5 having a spinning port 51 are arranged on one surface of the liquid feeding block 4 (the surface opposite to the surface on which the metering pump 2 is arranged). Since the spinning device 1 is provided with a plurality of spinning ports 51 in this way, it is possible to efficiently manufacture a fiber sheet such as a non-woven fabric made of spun fibers.

The arrangement pattern of the plurality of spinning devices 5 (spinning port 51) is not particularly limited. In the present embodiment, a spinning device row in which a plurality of (8 in the illustrated embodiment) spinning devices 5 are arranged at predetermined intervals in one direction on one surface of the liquid feeding block 4 is the spinning device row. A plurality of (two rows in the illustrated form) are provided at predetermined intervals in a direction orthogonal to the extending direction. Further, in the present embodiment, the plurality of spinning devices 5 are arranged in a staggered pattern. The term "staggered" as used herein refers to an arrangement in which the spinning devices 5 are misaligned (preferably half-pitch-shifted) between adjacent rows of spinning devices.

Each of the plurality of spinning devices 5 includes a nozzle having a spinning port 51 at the tip thereof. The nozzle is a hollow member made of a conductive material such as metal, communicates with the metering pump 2 via the metering discharge unit 3 and the outflow side flow path 42, and is a raw material liquid sent from the metering pump 2. Can be discharged from the spinning port 51.

In the present embodiment, each of the plurality of spinning devices 5 has a spout (not shown) for injecting a gas flow such as hot air in the vicinity of the spinning port 51, and the gas flow is ejected from the spout. In this state, the raw material liquid can be discharged from the spinning port 51 to perform spinning, and each spinning device 5 includes a gas flow generator 6. By bringing the raw material liquid discharged from the spinning port 51 into contact with the gas stream for spinning, the miniaturization of the fibers is promoted, and the production of ultrafine fibers such as nanofibers becomes easier. As the gas flow generator 6, a known gas flow generator 6 that can generate hot air or the like can be used without particular limitation.

As described above, as shown in FIG. 2, the spinning apparatus 1 includes a plurality of fixed-quantity discharge units 3 (16 in the illustrated form), and the plurality of fixed-quantity discharge units 3 and a plurality (16 in the illustrated form). ), Which has a one-to-one correspondence with the spinning port 51, and includes a single spinning port 51 having a one-to-one correspondence, a single fixed-quantity discharge unit 3, and an outflow-side flow path 42 connecting the two. It has a plurality of structures 20. That is, the quantitative spinning structure 20 includes a single spinning port 51, a single fixed-quantity discharge unit 3, and an outflow side flow path 42 connecting the two, and the spinning device 1 has the fixed-quantity spinning structure 20 as the number of spinning ports 51. The same number (16 in the illustrated form) is provided.

One of the main features of the spinning device 1 is that the outflow side flow paths 42 are independent of each other in the plurality of quantitative spinning structures 20. That is, in each of the plurality of quantitative spinning structures 20, the outflow side flow path 42 of the quantitative spinning structure 20 does not merge with the outflow side flow path 42 of the other quantitative spinning structure 20 and does not branch. It extends from a single fixed-quantity discharge unit 3 of the fixed-quantity spinning structure 20 to a single spinning port 51 of the fixed-quantity spinning structure 20. That is, in the spinning device 1, a dedicated outflow side flow path 42 is provided to each of the plurality of spinning ports 51 (spinning device 5), and each spinning port 51 is provided with a dedicated outflow side flow path 42 from the metering pump 2. The raw material liquid is sent through the liquid.

Such a characteristic configuration of the spinning device 1 is that in the spinning device 90 shown in FIG. 9 described above, a single outflow side flow path 96 extending from the metering pump 91 to the spinning port 94 branches in the middle and a plurality of outflows occur. This is in contrast to the side flow path 96. Due to such a characteristic configuration different from the conventional technique, the spinning device 1 can uniformly discharge the resin from a plurality of spinning ports, which was difficult in the conventional technique such as the spinning device 90, and has a tsubo. It is possible to efficiently produce a high-quality fiber sheet (nonwoven fabric) with no unevenness in quantity.

In the present embodiment, the plurality of quantitative spinning structures 20 are connected to each other via a single liquid feeding block 4, and the outflow side of each of the plurality of quantitative spinning structures 20 is contained in the single liquid feeding block 4. The flow path 42 is arranged. With such a configuration, parts related to liquid feeding (liquid feeding related parts) such as a heater, a filter, a pressure sensor, and a safety valve, which will be described later, are collectively installed in a single member (liquid feeding block 4). This makes it possible to simplify the configuration of the spinning apparatus 1 and obtain the best results with a relatively small number of component configurations.

In the present embodiment, the liquid feed block 4 has a heating function capable of heating the outflow side flow path 42 of each of the plurality of quantitative spinning structures 20. Specifically, as shown in FIG. 4, a heater (FIG. 4), which is a kind of heating means, is on the side surface of the liquid feed block 4 (the surface intersecting both the arrangement surface of the metering pump 2 and the arrangement surface of the spinning device 5). A heater insertion port 7 into which (not shown) can be inserted is provided. A plurality of heater insertion ports 7 are provided in each of the first block 43 and the second block 44 constituting the liquid feed block 4, and the plurality of heater insertion ports 7 are short of the liquid feed block 4 having a rectangular shape in a plan view. It is arranged intermittently in the hand direction. Each heater insertion port 7 extends over substantially the entire length in the longitudinal direction (direction in which the spinning device row extends) of the liquid feeding block 4 having a rectangular shape in a plan view, and the heater inserted into the heater insertion port 7 is also It extends over substantially the entire length of the liquid feed block 4 in the longitudinal direction. By inserting the heater into the heater insertion port 7, the raw material liquid flowing through the outflow side flow path 42 in the liquid feeding block 4 can be heated by the heater. As the heater, a known heater can be used without particular limitation. In the present embodiment, as described above, the liquid feed block 4 is configured so that heating means such as a heater can be intermittently arranged, whereby the outflow side flow path 42 of each of the plurality of quantitative spinning structures 20 can be heated. There is. Heating the raw material liquid in the outflow side flow path 42 leads to ease of control of the amount of resin discharged from the spinneret 51, and the resin can be uniformly discharged from the plurality of spinneret 51s with high accuracy. It will be possible.

In the present embodiment, the liquid feed block 4 has 1) a filter for filtering the raw material liquid (not shown), 2) a pressure sensor 9 for measuring the pressure in the outflow side flow path 42, and 3) an outflow side flow path 42. It comprises one or more liquid feed-related parts selected from safety valves that regulate the pressure inside, and the liquid feed-related parts are made compatible with each of a plurality of quantitative spinning structures 20.

The filter can be installed in, for example, one or both of the inflow side flow path 41 and the outflow side flow path 42. Examples of the location where the filter is installed in the inflow side flow path 41 include a connection portion with a raw material liquid supply source (melt extruder 11 in the illustrated embodiment) in the spinning device 1 or a vicinity thereof. As the location where the filter is installed in the outflow side flow path 42, it is preferable to arrange the filter in the outflow side flow path 42 of each quantitative spinning structure 20 from the viewpoint of being able to correspond to each of the plurality of quantitative spinning structures 20, for example, a plurality of. The boundary between each of the spinning devices 5 and the liquid feed block 4 or its vicinity may be mentioned. By installing the filter in the above-mentioned location, it becomes possible to remove carbonized resin, impurities, etc. contained in the raw material liquid, whereby clogging of the spinneret 51 is suppressed and the raw material liquid is smoothly discharged. Therefore, it may be easier to solve the problem of uniform discharge of the resin from the plurality of spinners 51. As the filter, a filter that can be used for filtering a raw material liquid containing a resin can be used without particular limitation, and for example, a sintered metal filter can be used.

The pressure in the outflow side flow path 42 measured by the pressure sensor is an index of the supply amount of the resin which is the raw material of the fiber to the spinneret 51. Therefore, by arranging the pressure sensor in the liquid feed block 4, the pressure sensor is arranged. It is possible to manage the amount of resin discharged from the spinneret 51, detect the clogging of the spinneret 51 at an early stage, and solve the problem of uniform discharge of the resin from a plurality of spinneret 51s. As the pressure sensor, a known pressure sensor that can be used for this type of application can be used without particular limitation.

The safety valve is useful because it can prevent the inconvenience of damaging the metering pump 2 when an excessive pressure load is applied. As the safety valve, for example, a valve seat, a valve body, and a drive unit for opening and closing the valve body are used, and when the pressure in the outflow side flow path 42 is equal to or less than a predetermined value, the valve body is used. Is closed, and when the pressure in the outflow side flow path 42 exceeds a predetermined value, the valve body opens, and the raw material liquid is discharged from the outflow side flow path 42 to the outside of the spinning device 1. Can be done.

Reference numeral 8 in FIG. 3 indicates a location where the pressure sensor and the safety valve are installed. In the embodiment shown in FIG. 3, 16 outflow side flow paths 42, which are the same number as the plurality of spinning ports 51, are arranged in the spinning device 1 (liquid feeding block 4), so that each of the plurality of quantitative spinning structures 20 is supported. From the viewpoint of enabling it, the number of installation points 8 of the pressure sensor and the safety valve is 16 corresponding to each outflow side flow path 42 (partially not shown). The location where the pressure sensor is installed and the location where the safety valve is installed are the same. In the form shown in FIG. 3, the pressure sensor 9 is installed at one of the 16 installation locations 8.

In the present embodiment, the discharge directions of the raw material liquids of the plurality of spinning ports 51 (16 in the illustrated embodiment) are the same as each other. However, as shown in FIG. 5, the plurality of spinning ports 51 (spinning device 5) are used. When viewed from the discharge direction, a virtual rectangle having a diagonal line connecting two spinning ports having the longest separation distance between the spinning ports 51 (spinning device 5) is created, and the virtual rectangle is used in the longitudinal direction thereof. The metering pump 2 preferably has a single center in the central region when it is divided into three equal parts, preferably in the central region M (the region shaded in the middle of FIG. 5) when it is further divided into three equal parts in the lateral direction. The single metering pump 2 and a plurality of (16 in the illustrated embodiment) metering discharge units 3 are connected to each other. In order to enable uniform discharge of the resin from the plurality of spinners 51, which is one of the main problems of the present invention, it is effective to make the flow path lengths of the plurality of outflow side flow paths 42 as uniform as possible. However, such a configuration makes it even easier.

As shown in FIG. 2, each of the plurality of (16 in the illustrated embodiment) outflow side flow paths 42 extends in the discharge direction of the raw material liquid (thickness direction of the liquid feed block 4) (hereinafter, "first". A portion (also referred to as a "part") and a portion extending in a direction orthogonal to the discharge direction (hereinafter, also referred to as a "second portion"), the first portion is typically a spinneret. Regardless of the position of 51 (spinning device 5), the outflow side flow paths 42 are substantially the same, but the second portion differs depending on the position of the spinning port 51 (spinning device 5), and the metering pump 2 (spinning device 5) is used. The distance from the fixed quantity discharge unit 3) increases. Therefore, in order to make the flow path lengths of the plurality of outflow side flow paths 42 as uniform as possible, it is sufficient to make the flow path lengths of the second portion as uniform as possible. Then, as described above, the single metering pump 2 in which the plurality of metering discharge units 3 corresponding to one-to-one corresponding to the plurality of outflow side flow paths 42 are connected to the plurality of spinning ports 51 (spinning device 5) is arranged. When arranged in the central region M of the virtual rectangle corresponding to the region, there is a relatively large room for adjusting the flow path length of the second portion of each outflow side flow path 42, so that it is easy to align them. become.

In the present embodiment, since the metering pump 2 (quantitative discharge unit 3) is arranged in the central region M as described above, as shown in FIG. 3, the second of the plurality of outflow side flow paths 42 is described. The portion extends radially from the metering pump 2 toward the outside of the spinning device 1 (liquid feeding block 4), whereby the flow path length of the outflow side flow path 42 of each of the plurality of metering spinning structures 20 is maximized. It is limited.

When the average value of the flow path lengths of the plurality of outflow side flow paths 42 is " _{LA Ave} " and the standard deviation is "σ", the flow path lengths of the plurality of outflow side flow paths 42 are " _{LA Ave} ± 3σ", respectively. If it is within the range, it can be evaluated that the variation in the flow path lengths of the plurality of outflow side flow paths 42 is small and the flow path lengths are relatively uniform. If it is within the range of "L _Ave ± 2σ", it can be evaluated that the variation in the flow path lengths of the plurality of outflow side flow paths 42 is smaller and the flow path lengths are relatively more uniform. The standard deviation σ is calculated by the following (Equation 1).

“ _Li ” in the above (formula 1) is the sum of the flow path lengths of each of the plurality of outflow side flow paths 42 included in the spinning device 1. The “flow path length of the outflow side flow path 42” here is the actual length from the metering discharge unit 3 (quantitating pump 2) to the spinning port 51. For example, in the present embodiment, as described above, the plurality of outflow side flow paths 42 are first portions extending in the discharge direction of the raw material liquid or the thickness direction of the liquid feed block 4 (first block 43, second block 44), respectively. And a second portion extending in a direction orthogonal to the discharge direction, the length of each of these portions, specifically, a portion extending in the thickness direction inside the first block 43 (the first portion). The length of the portion extending in the thickness direction inside the second block 44 (the first portion), and the length of the portion formed by overlapping the blocks 43 and 44 (the second portion). The total is the flow path length of the outflow side flow path 42. "N" in the above (formula 1) is the total number of outflow side flow paths 42 included in the spinning device 1, and is a natural number of 2 or more. Since n = 16 in this embodiment, the variable “i” in the above (Equation 1) is any one of 1 to 16. The average value L _Ave is an arithmetic mean value of the flow path lengths of a plurality of (16 in this embodiment) outflow side flow paths 42 included in the spinning device 1.

FIG. 6 shows a schematic configuration of a spinning device 1A, which is another embodiment of the spinning device of the present invention. The spinning device 1A will be described with a configuration different from that of the spinning device 1 described above, and the same configuration will be designated by the same reference numerals and description thereof will be omitted. The description of the spinning device 1 is appropriately applied to the configurations not particularly described in the spinning device 1A.

In the spinning device 1, one metering pump 2 is arranged for a plurality of (16) quantitative spinning structures 20, whereas in the spinning device 1A, a metering pump is provided for a plurality (4) quantitative spinning structures 20. 2 is arranged in the same number (4 units) as the plurality. That is, in the spinning device 1A, a dedicated metering pump 2 is provided to each of the plurality of spinning ports 51 (spinning device 5), and each spinning port 51 is provided with a dedicated outflow side flow path 42 from the dedicated metering pump 2. The raw material liquid is sent through the liquid. Each of the plurality of metering pumps 2 is connected to a single storage unit 10 for storing the raw material liquid. The supply source of the raw material liquid, such as the melt extruder 11 connected to the reservoir 10 or the spinning device 1, is not a single source as shown in FIG. 6, but is the same as the number of the quantitative spinning structures 20 (spinning ports 51). Therefore, the plurality of suppliers and the plurality of quantitative spinning structures 20 (spinning ports 51) may have a one-to-one correspondence. The spinning device 1A also produces the same effect as the spinning device 1.

The fiber diameter of the fiber spun in the present invention and the fiber diameter of the constituent fibers of the nonwoven fabric produced in the present invention are not particularly limited. For example, by spinning by a known electrospinning method using the above-mentioned spinning device 1, it is possible to spin nanofibers having a fiber diameter at or near the nano level, and a fiber sheet such as a non-woven fabric containing nanofibers can be spun. It is possible to manufacture.
In the present invention, the "nanofiber" (ultrafine fiber) refers to a fiber whose fiber diameter is preferably in the range of 0.1 μm or more and 7 μm or less when the fiber diameter is expressed by a circle-equivalent diameter.
The fiber diameter of various fibers such as nanofibers is measured by the following procedure. Cross-sectional length when 300 fibers are arbitrarily selected from the two-dimensional image observed by scanning electron microscope and excluding defects such as fiber lumps, fiber intersections, and polymer droplets, and lines perpendicular to the longitudinal direction of the fibers are drawn. Is measured, and the calculated average value of these is taken as the fiber diameter of the fiber.

The spinning device 1 can be used for various spinning methods such as melt spinning, solution spinning, wet spinning, dry spinning, melt blown, and electric field spinning (electrostatic spinning). The spinning device 1 is suitable for a melt-blown method and an electric field spinning method. The electric field spinning method is a raw material containing a resin as a spinning material in an electric field (electric field) generated by applying a high voltage to a conductive nozzle provided in a spinning device, a charged electrode arranged apart from the nozzle, and the like. It is a method of spinning by discharging a liquid, and the discharged raw material liquid is elongated in the electric field to form fibers having a small diameter. The electric field spinning method is roughly classified into a solvent type in which a resin-containing solution is used as a raw material liquid and a molten type in which a resin molten liquid is used as a raw material liquid, and the spinning device 1 can be applied to both.

As an example of a fiber sheet (specifically, non-woven fabric) manufacturing device by the melt blown method, a spinning device 1, a spinning space in which a raw material liquid discharged from each spinning port 51 of the spinning device 1 is used as a fiber, and a spinning space for capturing the fiber. Examples thereof include those provided with a collecting means for collecting, and the fibers are directly accumulated on the collecting means to form a fiber sheet. As the collecting means, known collecting means such as a net conveyor and a collecting screen can be used without particular limitation.

Further, as an example of a method for manufacturing a fiber sheet (specifically, for example, a non-woven fabric) by the melt blown method using the spinning device 1, a raw material liquid (resin-containing solution or resin melt) is discharged from each spinning port 51 of the spinning device 1. Examples thereof include a step of forming fibers (spinning step) and a step of directly accumulating the fibers to produce a nonwoven fabric. Such a manufacturing method can be carried out by using the fiber sheet manufacturing apparatus by the above-mentioned melt blown method.

As an example of an apparatus for producing a fiber sheet (specifically, for example, a non-woven fabric) by an electrospinning method, a spinning apparatus 1, a spinning space in which a raw material liquid discharged from each spinning port 51 of the spinning apparatus 1 is used as a fiber, and the spinning space. It is provided with an electric field generating means for generating an electric field (electric field) and a collecting means for collecting the fibers, and the fibers are directly accumulated on the collecting means to form a fiber sheet. Can be mentioned. The electric field generating means includes various power sources, electrodes and the like. The electric field is generated by, for example, grounding the conductive nozzle having a spinning port 51 and applying a voltage to the charged electrodes arranged apart from the nozzle by using a power source. It can be generated between the charged electrode and the charged electrode. Further, the collecting means may be grounded or a voltage may be applied. As the manufacturing apparatus having such a configuration, for example, the one described in Japanese Patent Publication No. 2017-190552 can be used.

Further, as an example of a method for manufacturing a fiber sheet (specifically, for example, a non-woven fabric) by an electrospinning method using a spinning device 1, a raw material liquid is discharged from each spinning port 51 of the spinning device 1 and an electric field (specifically, a non-woven fabric) is applied to the raw material liquid. Examples thereof include a step of forming fibers by applying an electric field) (electromagnetic spinning step) and a step of directly integrating the fibers to produce a fiber sheet. Such a manufacturing method can be applied to both the solvent type electric field spinning method and the molten type electric field spinning method. Such a manufacturing method can be carried out by using the non-woven fabric manufacturing apparatus by the above-mentioned electric field spinning method.

In the electric field spinning method, the raw material liquid containing the resin discharged from the spinning port 51 is refined while being stretched by the Coulomb force generated inside the spinning port 51 and preferably by the injection of the gas flow (hot air). .. When a resin-containing solution containing a resin and a solvent is used as the raw material liquid, the solvent evaporates instantly during stretching and the resin solidifies to form a fine fibrous substance. When a resin melt is used as the raw material liquid, the resin melt is cooled and solidified while being stretched to become a fine fibrous product. The solidified fibrous material is randomly deposited on the collecting means. As a result, a non-woven fabric having fine-diameter fibers and having little unevenness in basis weight is formed.

The spinning device 1 can be used to carry out a fiber manufacturing method (hereinafter, also referred to as "fiber manufacturing method A") having the following four steps.
1) Supply step: A step of supplying a raw material liquid containing a resin to a single metering pump 2.
2) Distributing step: A step of distributing the raw material liquid to a plurality of outflow side flow paths 42 that are independent of each other and branch from the metering pump 2.
3) Liquid feeding step: A step of quantitatively sending the raw material liquid distributed to the plurality of outflow side flow paths 42 to a plurality of spinners 51 corresponding to the plurality of outflow side flow paths 42 on a one-to-one basis.
4) Spinning process: A process of forming fibers by discharging raw material liquids from a plurality of spinning ports 51.

The supply step of the fiber manufacturing method A is carried out in the spinning apparatus 1 by supplying the raw material liquid from the melt extruder 11 to the metering pump 2 via the inflow side flow path 41.
In the distribution step of the fiber manufacturing method A, in the spinning apparatus 1, a plurality of independent liquids are branched by branching the raw material liquid via a plurality of quantitative discharge units 3 (quantitative discharge unit forming member 30) connected to the metering pump 2. It is carried out by distributing to the outflow side flow path 42.
According to the fiber manufacturing method A having the above four steps, as demonstrated in the examples described later, the discharge weight (spinning amount) of the resin per unit time of each of the plurality of spinners 51 and their It is possible to keep the difference from the arithmetic mean value within 10% of the arithmetic mean value, that is, to make the variation in the discharge amount of the plurality of spinners 51 extremely small.

Further, the spinning device 1 and the spinning device 1A can each be used to carry out a fiber manufacturing method (hereinafter, also referred to as "fiber manufacturing method B") having the following three steps.
1) Distributing step: A step of distributing a raw material liquid containing a resin to a plurality of outflow side flow paths 42 independent of each other.
2) Liquid feeding process: The raw material liquid distributed to the plurality of outflow side flow paths 42 is quantitatively distributed to a plurality of spinners 51 corresponding to the plurality of outflow side flow paths 42 on a one-to-one basis by using the pump 2. The process of sending.
3) Spinning process: A process of forming fibers by discharging raw material liquids from a plurality of spinning ports 51.

The fiber manufacturing method B is characterized in that after the raw material liquid is distributed to a plurality of the raw material liquids, the distributed raw material liquids are quantitatively sent to each spinning port 51. The distribution step of the fiber manufacturing method B is characterized in that the raw material liquid does not need to be quantitatively distributed and is quantitatively fed in the liquid feeding step. The spinning process of the fiber manufacturing method B is the same as that of the fiber manufacturing method A.
When the fiber manufacturing method B is carried out using the spinning device 1, the raw material liquid is distributed using a single metering pump 2 in the distribution step, and the single metering pump is used in the subsequent liquid feeding step. Using No. 2, quantitative feeding of the distributed raw material liquid to each spinning port 51 is carried out. Further, when the fiber manufacturing method B is carried out using the spinning device 1A, it is the same as the case where the spinning device 1 is used except that the number of metering pumps 2 is a plurality.
Even in the fiber manufacturing method B having the above three steps, the difference between the discharge weight (spinning amount) of the resin per unit time of each of the plurality of spinning ports 51 and their arithmetic mean values can be determined by the arithmetic mean value. It can be within 10%.

Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to the following examples.

[Example 1]
A spinning device having the same configuration as the spinning device 1 described above, that is, a fixed-quantity spinning structure including a single spinning port corresponding to one-to-one, a single fixed-quantity discharge unit, and an outflow-side flow path connecting the two. The 16 quantitative spinning structures are a spinning device in which the outflow side flow paths are independent of each other. ”In other words, the outflow side flow paths extending from the metering pump to the spinning port do not branch in the middle. A non-woven fabric made of an aggregate of nanofibers having a fiber diameter of 920 nm was produced by a melt-type electrospinning method using a spinning device that did not merge with the outflow side flow path. In the spinning apparatus used, the average value L _Ave of the flow path lengths of the plurality of outflow side flow paths was 297 mm, the standard deviation σ was 91.8 mm, and the above-mentioned “LA _Ave ± 3σ” was satisfied. As the raw material liquid, a resin melt prepared by heating polypropylene resin to a temperature higher than its melting point was used. The implementation conditions of the electric field spinning method are a voltage of -10 kV, a separation distance of 300 mm between the tip of the nozzle (spinning port) and the collecting means (net conveyor), and a target spinning amount (target discharge weight of resin) of 6 g / min. did.

[Comparative Example 1]
As the spinning device, the same as in Example 1 except that a spinning device having the same configuration as the above-mentioned spinning device 90, that is, a spinning device in which the outflow side flow path extending from the metering pump to the spinning port is branched in the middle is used. , A non-woven fabric made of an aggregate of nanofibers having a fiber diameter of 1540 nm was produced by a melt-type electrospinning method.

For the spinning devices of each Example and Comparative Example, the spinning amount (residue weight of the resin) per unit time of each spinning port during the production of the non-woven fabric was measured. Specifically, the resin is discharged from each spinning port toward the basket as a measuring container for 1 minute to spin the fibers, and the weight of the fibers collected in the measuring container is measured to spin the fibers per unit time. The amount was calculated.

FIG. 7 shows the 16 spinning device Nos. The graph of the spinning amount per unit time of 1 to 16, FIG. 8, shows the 12 spinning device Nos. Graphs of spinning amount per unit time from 1 to 12 are shown respectively. The details of each data are described below.
(Example 1)
-Average value of spinning amount (Ave): 6.12 g / min
-Maximum value of spinning amount (Max): 6.18 g / min
-Minimum value of spinning amount (Min): 6.02 g / min
・ (| Max-Ave | × 100) / 100 = 1.0%
・ (| Min-Ave | × 100) / 100 = 1.6%
(Comparative Example 1)
-Average value of spinning amount (Ave): 5.97 g / min
-Maximum value of spinning amount (Max): 6.66 g / min
-Minimum value of spinning amount (Min): 5.52 g / min
(| Max-Ave | x100) / 100 = 11.46%
・ (| Min-Ave | × 100) / 100 = 7.62%

Comparative Example 1 was carried out while the difference between the spinning amount (residue weight of the resin) per unit time of each of the plurality of spinning ports and their arithmetic mean values exceeded 10% of the arithmetic mean values. In Example 1, it is 2% or less, and the small variation in the spinning amount of Example 1 is obvious from the graph of FIG. 7. From this, in order to uniformly discharge the resin from a plurality of spinning ports and perform spinning, the outflow side flow paths of the plurality of quantitative spinning structures are independent of each other (the outflow side extending from the metering pump to the spinning port). It can be seen that it is effective that the flow path does not branch in the middle and does not merge with other outflow side flow paths).

1,1A, 90 Spinning device 2,91 Metering pump 20 Metering spinning structure 3 Metering discharge part 30 Metering discharge part forming member 4,92 Liquid feed block 41,95 Inflow side flow path 42,96 Outflow side flow path 43 1st block 44 2nd block 5,93 Spinning device 51,94 Spinning port 6 Gas flow generator 7 Heater insertion port 8 Pressure sensor and safety valve installation location 9 Pressure sensor 10 Reservoir 11 Melt extruder

Claims (10)

A plurality of spinning ports that discharge the raw material liquid containing the resin, a metering pump that feeds the raw material liquid to the spinning port via the outflow side flow path, and a metering that connects the metering pump and the outflow side flow path. A spinning device equipped with a discharge unit,
It is provided with a plurality of the fixed-quantity discharge units.
The fixed quantity discharge unit and the spinneret have a one-to-one correspondence, and include a single spinneret and a single fixed quantity discharge unit corresponding to the one-to-one correspondence, and the outflow side flow path connecting the two. It has multiple spinning structures and
The plurality of quantitative spinning structures are spinning devices in which the outflow side flow paths are independent of each other. The plurality of quantitative spinning structures are connected to each other via a single liquid feeding block, and the outflow side flow path of each of the plurality of quantitative spinning structures is arranged in the liquid feeding block. Item 1. The spinning apparatus according to Item 1. The spinning device according to claim 2, wherein the liquid feed block has a heating function capable of heating the outflow side flow path of each of the plurality of quantitative spinning structures. The liquid feed block is one or two selected from a filter for filtering the raw material liquid, a pressure sensor for measuring the pressure in the outflow side flow path, and a safety valve for adjusting the pressure in the outflow side flow path. The spinning apparatus according to claim 2 or 3, further comprising the above-mentioned liquid-feeding-related parts, wherein the liquid-feeding-related parts can be adapted to each of the plurality of quantitative spinning structures. The spinning apparatus according to any one of claims 2 to 4, wherein the liquid feeding block is configured to be redividable into a plurality of parts. The discharge directions of the raw material liquids of the plurality of spinners are the same as each other, and when the plurality of spinners are viewed from the discharge directions, the two spinners having the longest separation distance between the spinners are connected. A single metering pump is arranged in the central region when a virtual rectangle having a virtual straight line as a diagonal line is created and the virtual rectangle is divided into three equal parts in the longitudinal direction thereof, and the single metering pump and a plurality of metering pumps are arranged. The spinning apparatus according to any one of claims 1 to 5, wherein the fixed-quantity discharge unit is connected to the spinning device. The spinning device according to any one of claims 1 to 6, which is a nanofiber spinning device. A fiber sheet manufacturing apparatus comprising the spinning apparatus according to any one of claims 1 to 7. A method for manufacturing a fiber sheet using the manufacturing apparatus according to claim 8. A distribution process that distributes the raw material liquid containing the resin to multiple outflow side channels that are independent of each other.
A liquid feeding step in which the raw material liquid distributed in the plurality of outflow side flow paths is quantitatively sent to a plurality of spinners corresponding to the plurality of outflow side flow paths on a one-to-one basis by using a pump.
It has a spinning process in which the raw material liquid is discharged from a plurality of the spinning ports to form fibers.
A method for producing a fiber, wherein the difference between the discharge weight of the resin per unit time of each of the plurality of spinners and the arithmetic mean value thereof is within 10% of the arithmetic average value.

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