JP2017155367A - Manufacturing method and manufacturing installation of non-woven fabric - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of non-woven fabric which can remove fiber waste adhering to transportation belt easily when the non-woven fabric is formed.SOLUTION: A manufacturing method of non-woven fabric includes: a first step of producing fiber and forming the non-woven fiber by accumulating the produced fiber on backing supplied to a major plane of a ringed transportation belt; a second step of separating the non-woven fabric with the backing from the transportation belt; and a third step of removing fiber waste remaining on the transportation belt with a jig. The major plane of the transportation belt has steps with edge faces facing with the jig. The step is formed at least at both ends of a vertical direction to the move direction of the transportation belt. In the third step, the fiber waste is removed by contacting the major plane of the transportation belt and the edge face of the step with the jig.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a nonwoven fabric manufacturing method and a manufacturing apparatus suitable for removing fiber waste adhering to a conveyor belt that transports a substrate on which fibers are deposited.

  Nonwoven fabrics are used for various purposes in addition to filter media. A nonwoven fabric is manufactured by supplying a base material to the main surface of the conveyance belt of a production line, for example, and depositing the produced | generated fiber on a base material. At this time, in order to make the fiber distribution in the nonwoven fabric as uniform as possible, the fibers are deposited in a wider range than the base material. Therefore, fiber scraps are attached to the transport belt after separating the nonwoven fabric and the base material. The conveyor belt is generally annular and is continuously driven to rotate by rollers, and the formation of a nonwoven fabric by the deposition of fibers on the surface and the separation of the nonwoven fabric from the conveyor belt are repeated. Therefore, it is required to remove the fiber waste adhering to the conveyance belt before depositing new fibers. However, conventionally, removal of such fiber waste has been performed manually using an adhesive sheet, a brush, or the like.

  Patent Document 1 teaches that when producing an air-laid nonwoven fabric, gas is supplied from the top of the chamber by a gas discharge nozzle, and fiber waste is discharged from the chamber.

Japanese Patent Application Laid-Open No. 2015-503682

  The conveyance belt has a certain degree of adhesiveness to make it easier to hold the base material, and is difficult to remove if fiber waste adheres when manufacturing the nonwoven fabric. If the fibers are deposited again in a state where the fiber waste adhering to the conveyance belt is not completely removed, the nonwoven fabric with the fiber waste adhering to the substrate may be conveyed to a subsequent process. If fiber scraps fall off in a later process, the inside of the production facility is contaminated.

  The objective of this invention is providing the manufacturing method and manufacturing apparatus of a nonwoven fabric which can remove easily the fiber waste adhering to a conveyance belt, when forming a nonwoven fabric.

One aspect of the present invention is a method of manufacturing a nonwoven fabric containing fibers,
A first step of generating a fiber, and depositing the generated fiber on a base material supplied to a main surface of an annular conveyance belt to form a nonwoven fabric;
A second step of separating the nonwoven fabric together with the base material from the transport belt;
A third step of removing fiber waste remaining on the conveyor belt with a jig,
The main surface of the conveyor belt has a step having an end surface facing the jig,
The step is formed at least at both ends in a direction perpendicular to the moving direction of the conveyor belt,
In the third step, the present invention relates to a method for producing a nonwoven fabric, wherein the fiber scrap is removed by bringing the main surface of the transport belt and the end surface of the step into contact with the jig.

Another aspect of the present invention is a base material supply unit that supplies a base material to the main surface of the annular transport belt;
A spinning mechanism for generating fibers and depositing the fibers on the substrate to form a nonwoven fabric;
A jig for removing fiber waste remaining on the conveyor belt after the nonwoven fabric and the substrate are separated from the conveyor belt,
The main surface of the conveyor belt has a step having an end surface facing the jig,
The step is formed at least at both ends in a direction perpendicular to the moving direction of the conveyor belt,
The said fiber waste is related with the manufacturing apparatus of the nonwoven fabric removed by making the said jig | tool contact the main surface of the said conveyance belt, and the end surface of the said level | step difference.

  According to this invention, when forming a nonwoven fabric, the fiber waste adhering to a conveyance belt can be removed easily.

It is a figure which shows roughly the structure of an example of the manufacturing apparatus of the nonwoven fabric which concerns on one Embodiment of this invention. It is a schematic sectional drawing for demonstrating the fiber waste removal system by the cleaning unit with which the manufacturing apparatus of FIG. 1 is provided. It is a side view which shows a mode that the fiber waste is removed with a brush in a conveyance belt in FIG. It is a side view which shows typically a mode that fiber waste is removed from another conveyance belt with a brush. It is a side view which shows typically a mode that textile waste is further removed from another conveyance belt with a brush. It is a side view which shows a mode that fiber waste is removed with a brush from another conveyance belt. It is a side view which shows typically a mode that textile waste is removed with a brush from another conveyance belt. FIG. 6 is a schematic perspective view for explaining a state of a step in a direction perpendicular to the moving direction of the transport belt. It is a schematic perspective view for demonstrating the state of the level | step difference in the direction perpendicular | vertical to the moving direction of another conveyance belt. Furthermore, it is a schematic perspective view for demonstrating the state of the level | step difference in the direction perpendicular | vertical to the moving direction of another conveyance belt.

[Method and apparatus for producing nonwoven fabric]
A method for producing a nonwoven fabric containing fibers according to the present invention,
A first step of generating fibers (first fibers) and depositing the generated fibers on a base material supplied to the main surface of the annular transport belt to form a nonwoven fabric (first nonwoven fabric);
A second step of separating the nonwoven together with the base material from the transport belt;
And a third step of removing fiber waste remaining on the conveyor belt with a jig. The main surface of the conveyor belt has a step having an end surface facing the jig, and the step is formed at both ends in a direction perpendicular to the moving direction of the conveyor belt. In the third step, the main surface of the transport belt and the end face of the step (and / or fiber waste applied to the end face) are brought into contact with the jig to remove fiber waste.

  In the spinning method in which a nonwoven fabric is formed while producing fibers, the nonwoven fabric is formed by depositing fibers on a base material supplied to the main surface of the transport belt. At this time, the fibers deposited in a wider range than the base material remain on the transport belt as fiber waste when the nonwoven fabric is separated from the transport belt together with the base material. At least the surface layer of the conveyor belt is made of a material having a certain degree of tackiness such as silicone resin in order to easily hold the base material, and it is difficult to remove if fiber waste adheres when manufacturing the nonwoven fabric. If the fibers are deposited again in a state where the fiber waste adhering to the conveyance belt is not completely removed, the nonwoven fabric with the fiber waste adhering to the substrate may be conveyed to a subsequent process. In addition, if fiber scraps fall off in a later process, the inside of the manufacturing facility is contaminated. In particular, when the nonwoven fabric and the base material are crimped at a crimping portion including a roller or the like, if fiber waste adheres to the roller and solidifies, it is not possible to perform proper crimping, and the quality of the nonwoven fabric is impaired.

  Conventionally, fiber waste adhered to the conveyor belt is manually removed with an adhesive sheet or brush, but fiber waste is difficult to remove and the operation itself is complicated. Therefore, it is industrially very useful if the operation of removing the fiber waste from the conveyor belt can be performed as a series of steps in the production of the nonwoven fabric.

  In the present invention, a step having an end surface facing a jig for removing fiber waste is formed on at least both ends of the main surface of the conveying belt in a direction perpendicular to the moving direction of the conveying belt. When the jig is brought into contact with the main surface of the conveyor belt to remove the fiber waste, the above-described step is utilized, so that the fiber waste can be easily removed. Further, in the production of a nonwoven fabric, the removal of fiber waste can be performed as a series of steps, which is extremely simple and advantageous in terms of cost.

  Note that both end portions in the direction perpendicular to the moving direction of the transport belt are regions including at least a region outside the region where the base material is arranged in the direction perpendicular to the moving direction of the transport belt, preferably the transport belt It includes a region outside the region where the substrate is arranged in a direction perpendicular to the moving direction and a region near the end of the substrate inside.

  The nonwoven fabric is formed, for example, by conveying the substrate from the upstream to the downstream of the production line and continuously depositing fibers on the main surface of the conveyed substrate. When the laminate of the base material and the nonwoven fabric is separated from the transport belt, a step of removing fiber waste remaining on the transport belt is performed. Such a series of steps includes, for example, (1) a base material supply unit that supplies the base material to the main surface of the annular transport belt, and (2) fiber is generated and the fiber is deposited on the base material to form the nonwoven fabric. The manufacturing apparatus includes a spinning mechanism to be formed, and (3) a jig that removes the fiber waste remaining on the conveyor belt after separating the nonwoven fabric and the base material from the conveyor belt. Here, the main surface of the transport belt has a step having an end surface facing the jig, and the step is formed at both ends in a direction at least perpendicular to the moving direction of the transport belt. And fiber waste is removed by making a jig | tool contact the main surface of a conveyance belt, and the end surface of a level | step difference.

  Hereinafter, the nonwoven fabric production method and production apparatus will be described more specifically with reference to the drawings as appropriate. However, the present invention is not limited to the following production apparatus. The following manufacturing apparatus includes an electrospinning mechanism as a spinning mechanism.

  FIG. 1 is a diagram schematically showing a configuration of an example of a nonwoven fabric manufacturing apparatus according to the present invention. In FIG. 1, a laminated nonwoven fabric 10 is formed in which a substrate (porous substrate) 1, a nonwoven fabric, and a protective layer 3 that protects the nonwoven fabric are laminated in this order.

  First, the base material 1 is prepared and conveyed from upstream to downstream of the production line of the production apparatus 200. In the uppermost stream of the manufacturing apparatus 200, a base material supply unit 201 is provided in which the base material 1 wound in a roller shape is accommodated. The base material supply unit 201 rotates the supply reel 12 by the motor 13 and supplies the base material 1 wound around the supply reel 12 to the transport roller 11 of the production line.

  The substrate 1 is conveyed by the conveying roller 11 to an electrospinning apparatus 202 including an electrospinning unit (not shown). The electrospinning mechanism included in the electrospinning unit is a positively charged discharge body (nozzle) 23 for discharging a raw material liquid containing a fiber raw material, which is installed above the apparatus, and the discharged raw material liquid. A charging means (see below) and a conveyor 21 that conveys the base material 1 disposed so as to face the emitter 23 from the upstream side to the downstream side are provided. The transport conveyor 21 includes a pair of transport rollers 21b arranged at intervals, and an annular transport belt 21a that covers the peripheral surfaces of the pair of transport rollers 21b. When the pair of transport rollers 21b rotate in the same direction, the transport belt 21a moves, and thereby the base material 1 supplied to the main surface of the transport belt 21a is transported along the moving direction of the transport belt 21a. The The conveyor 21 functions as a collector unit that collects the fibers 2F together with the base material 1. The number of electrospinning units is not particularly limited, and may be one or two or more.

  On the side of the emitter 23 facing the main surface of the substrate 1, a plurality of raw material liquid outlets (not shown) are provided. The emitter 23 is installed above the electrospinning unit, and the second support 25 extending downward from the first support 24 parallel to the conveying direction of the substrate 1 causes the longitudinal direction of the emitter 23 to be the main of the substrate 1. It is supported so as to be parallel to the surface. The first support 24 may be movable so as to swing the emitter 23 in a direction perpendicular to the transport direction of the substrate 1.

  The charging means includes a voltage applying device 26 that applies a voltage to the emitter 23 and a counter electrode 27 that is installed in parallel with the transport conveyor 21. The counter electrode 27 is grounded. Thereby, a potential difference (for example, 20 kV to 200 kV) corresponding to the voltage applied by the voltage application device 26 can be provided between the emitter 23 and the counter electrode 27. The configuration of the charging unit is not particularly limited. For example, the counter electrode 27 may be negatively charged. Moreover, you may comprise the belt part of the conveyance conveyor 21 from a conductor instead of providing the counter electrode 27. FIG.

  The emitter 23 is made of a conductor, has a long shape, and is hollow inside. The hollow portion serves as a storage portion that stores the raw material liquid 22. The raw material liquid 22 is supplied from the raw material liquid tank 29 to the hollow of the emitter 23 by the pressure of the pump 28 communicating with the hollow portion of the emitter 23. The raw material liquid 22 is discharged from the discharge port toward the main surface of the substrate 1 by the pressure of the pump 28. The discharged raw material liquid 22 undergoes electrostatic explosion while moving in the space (generation space) between the emitter 23 and the base material 1 in a charged state, and generates a fibrous material (fiber 2F). The produced fibers 2F are deposited on the main surface of the substrate 1 to form a nonwoven fabric.

  The spinning mechanism is not limited to the above configuration. Any mechanism that can generate the fibers 2F in a predetermined fiber generation space and deposit the generated fibers 2F on the main surface of the substrate 1 can be used without particular limitation.

  The laminate of the base material 1 and the nonwoven fabric formed by the electrospinning apparatus 202 is separated from the transport belt 21a and is supplied to the subsequent apparatus (or process). Fiber scraps remain on the main surface of the conveyor belt 21a after the laminate is removed. The manufacturing apparatus 200 according to the present embodiment includes a cleaning unit 70 for removing the fiber waste. Fiber waste is removed by the cleaning unit 70 from the main surface of the conveyor belt 21a that is moving by the rotation of the conveyor roller 21b. And the base material 1 is again supplied from the base material supply part 201 to the main surface of the conveyance belt 21a from which the fiber waste has been removed.

  The laminate of the base material and the nonwoven fabric separated from the transport belt 21 a is transported to the adhesive application unit 203. In the adhesive application unit 203, the adhesive 4 is applied to the base material 1 from above the base material 1 through the nonwoven fabric.

  For example, the adhesive application unit 203 forms an adhesive tank 32 for storing the adhesive 4 installed above the adhesive application unit 203 and a line-shaped region on the base material 1 with the adhesive 4. An applicator 34 having a nozzle 33 for coating, and a transport roller 31 for transporting a laminate of a base material and a nonwoven fabric downstream are provided. The adhesive tank 32 or the nozzle 33 includes a heating device (not shown). For example, the adhesive 4 that is a hot-melt resin is discharged while being melted.

  The laminate to which the adhesive 4 has been applied is then conveyed to a protective layer laminating apparatus 204 that includes a conveyance roller 41. In the protective layer laminating apparatus 204, the protective layer 3 is supplied from above the nonwoven fabric, and is laminated on the base material 1 via the adhesive 4 and the nonwoven fabric. When the protective layer 3 is long, the protective layer 3 may be wound around the reel 42 as in the case of the substrate 1. In this case, the protective layer 3 is laminated on the main surface of the nonwoven fabric while being unwound from the reel 42 rotated by the motor 43.

  The laminate obtained by disposing the protective layer 3 on the main surface of the nonwoven fabric is conveyed to the crimping unit 205. The pressure bonding part 205 includes a pair of pressure rollers 51 and 52 arranged vertically. The laminated nonwoven fabric 10 is formed by sandwiching and pressing the laminate between the pair of pressure rollers 51 and 52 at the crimping portion 205.

  Finally, the laminated body 10 is unloaded from the pressure-bonding unit 205 and is conveyed via the roller 51 to the collecting unit 206 disposed on the further downstream side. The collection unit 206 includes, for example, a collection reel 52 that winds the laminated nonwoven fabric 10 being conveyed. The collection reel 52 is rotationally driven by a motor 53. In addition, what is necessary is just to press the nonwoven fabric laminated | stacked on the base material 1 with the crimping | compression-bonding part 205, when not protecting the protective layer 3. FIG. In this case, it is not particularly necessary to provide the adhesive application portion 203, and an adhesive may be applied to the surface of the substrate 1 before forming the nonwoven fabric as necessary.

  When a releasable sheet is used as the base material 1, the base material 1 is peeled off from the laminated nonwoven fabric 10 obtained by the pressure-bonding part 205, and is collected by winding it with a recovery reel. The peeled non-woven fabric (or the laminate of the non-woven fabric and the protective layer 3) may be taken out from the crimping portion 205 and collected by the collecting device 206.

(Third step and cleaning unit)
Hereinafter, the third step (and the cleaning unit for removing fiber waste) will be described more specifically.
FIG. 2 is a schematic cross-sectional view for explaining a fiber waste removal system by the cleaning unit 70 in the manufacturing apparatus of FIG. In the conveyor 21, the conveyor belt 21 a is moved in the direction of arrow B (the direction of movement of the conveyor belt) by the rotation of the conveyor roller 21 b, and the base material 1 supplied to the main surface of the conveyor belt 21 a is moved along with the arrow. It is conveyed in the direction A (the conveyance direction of the substrate 1). When the main surface of the conveyor belt 21a is facing upward, fibers are deposited on the base material 1 that moves together with the conveyor belt 21a, and the nonwoven fabric 2 is formed. The transport belt 21a moves along the peripheral surface of the transport roller 21b located on the downstream side in the transport direction A of the base material 1, and the main surface faces downward at a position where it does not come into contact with the transport roller 21b. On the other hand, the laminate separated from the conveyance belt 21a at the position of the conveyance roller 21b is provided to subsequent apparatuses and processes along the conveyance direction A.

  The cleaning unit 70 includes a brush 70a as a jig for removing the fiber waste f remaining on the main surface of the transport belt 21a. In FIG. 2, the cleaning unit 70 is installed below the transport conveyor 21. However, the cleaning unit 70 is not particularly limited to this case, and the laminate of the base material 1 and the nonwoven fabric 2 is transported along the transport belt 21 a in the movement path of the transport belt 21 a. What is necessary is just to be downstream rather than the position which leaves | separates. In the example of FIG. 2, after the laminate of the base material 1 and the nonwoven fabric 2 is separated from the transport belt 21a, it is installed below the main surface of the transport belt 21a when the main surface of the transport belt 21a is downward. The brush 70a is brought into contact with the main surface of the transport belt 21a. Thereby, the fiber waste f remaining on the main surface of the conveyor belt 21a is removed.

  FIG. 3 is a side view schematically showing how the fiber waste f is removed by the brush 70a in FIG. The conveyor belt 21a has a step S1 having an end surface E1 facing a brush 70a as a jig (a region (specifically, a hair portion of the brush 70a) from which at least fiber waste f of the jig is removed). Yes. In FIG. 3, the conveyor belt 21a is formed in an annular shape by overlapping and connecting the ends of at least one belt-like belt, and a step S1 is formed at this connecting portion. At this time, the end on the outer peripheral side overlapped with the end on the inner peripheral side of the belt protrudes to the outer peripheral side from the main surface of the end on the inner peripheral side. E1 is formed. Note that. When the conveyor is viewed from the side, the side closer to the center of the conveyor is the inner peripheral side, and the side far from the center is the outer peripheral side.

  In the end surface E1, when the transport belt 21a is moved along the movement direction B, the brush 70a is in contact with the main surface of the transport belt 21a on the downstream side of the end surface E1 in the vicinity of the step S1, and the end surface E1 ( Alternatively, it is formed so as to also contact the fiber waste f) applied to the end face E1. The end surface E1 is formed so that it can be seen from the moving direction B of the conveyor belt 21a. That is, the end surface E1 is formed toward the moving direction B of the conveyor belt 21a. When the end surface E1 is opposed to the brush 70a (specifically, the bristle portion of the brush 70a), the end surface E1 of the transport belt 21a moving along the moving direction B (or fiber waste f applied to the end surface E1). In addition, the brush 70a can be contacted more reliably. Since the fiber waste f is continuously attached in a non-woven fabric form on the main surface of the transport belt 21a, it can be scraped continuously with the brush 70a starting from the step S1. Thus, in the present invention, the fiber waste f can be easily removed by the jig (brush 70a) using the step S1.

  Note that the end face of the step faces (or comes into contact with) the jig means that the end face faces (or comes into contact) with at least the region of the jig that removes fiber waste (the hair part in the case of a brush). means. Similarly, the fact that the main surface of the conveyor belt is in contact with the jig means that the main surface of the conveyor belt is in contact with at least the region of the jig from which fiber waste is removed (the hair part in the case of a brush). To do.

  4 to 7 are side views schematically showing how the fiber waste f is removed by the brush 70a when the steps of the steps of the conveyor belt are different. 4 to 7 are the same as FIG. 3 except for the state of the step. 4 to 7, the same components as those in FIGS. 2 and 3 are denoted by the same reference numerals.

  In FIG. 4, the conveyance belt 121a has a step S2 having an end surface E2 inclined with respect to the main surface of the conveyance belt 121a. When the conveying belt 121a and the brush 70a are in contact with each other, the end surface E2 is in contact with the main surface of the conveying belt 121a on the downstream side of the end surface E2 in the moving direction B at the step S2 and in the vicinity thereof. The end surface E2 needs to be formed so as to come into contact with the end surface E2. Therefore, the end surface E2 is formed so that the thickness of the conveyor belt 121a increases from the downstream side in the movement direction B toward the upstream side (the height of the step S2 increases), and thereby the end surface E2 faces the brush 70a. Let By forming the step S2 having such an end surface E2, the brush 70a can be more reliably brought into contact with the end surface E2 of the conveying belt 121a moving along the moving direction B, and the fiber waste f can be easily obtained. Can be removed.

  In FIG. 5, the conveyance belt 221a has a step S3 having an end face E3 facing the brush 70a. The step S3 is formed at a portion where the ends of at least one belt-like belt are connected to each other, and the ends of the belt-like belt are connected so that the end surfaces are in contact with each other. At this time, the step S3 is formed by making the thickness of one end portion larger than the thickness of the other end portion connected to the one end portion, and the thickness is larger than the end portion having the smaller thickness. The end face E3 is formed by projecting the end on the outer peripheral side. In order for the end surface E3 to face the brush 70a, the thickness of the end portion of the belt disposed on the downstream side in the moving direction B of the transport belt 221a is reduced, and the thickness of the end portion of the belt disposed on the upstream side is increased. Then, by using the step S3 including the end surface E3, the fiber waste f attached to the main surface of the transport belt 221a can be easily removed by the brush 70a.

  In FIG. 5, in order to form the step S3, the main surface of the conveyance belt 221a is inclined so that the thickness of the conveyance belt 221a increases along the movement direction B on the upstream side from the end surface E3 in the movement direction B. It is in a state. However, it is not particularly limited to this case. For example, the main surface is inclined so that the thickness of the conveyor belt 221a is constant upstream from the end surface E3 in the moving direction B, and the thickness of the conveyor belt 221a decreases toward the end surface E3 downstream of the end surface E3. A step S3 may be formed.

In FIG. 6, the conveyance belt 321a includes an annular base belt 321c and a surface belt 321d covering the base belt 321c. The conveyor belt 321a has at least one gap s where the surface belt 321d is interrupted. The thickness of the surface belt 321d is small on the downstream side in the movement direction B of the conveying belt 321a with the gap s interposed therebetween, and the thickness is large on the upstream side. A step S4 having an end surface E4 is formed on the conveyor belt 321a by the portion where the thickness of the surface belt 321d is protruded to the outer peripheral side with respect to the portion where the thickness is small across the gap s. The end surface E4 faces the brush 70a, and the waste fiber f is removed using the end surface E4 by bringing the brush 70a into contact with the moving conveyor belt 321a.
Although FIG. 6 shows the case where the thickness of the surface belt is different with a gap in between, the thickness of the surface belt may be the same.

  In FIG. 7, a convex portion P is formed on the main surface of the annular transport belt 421a so as to protrude from the main surface of the transport belt 421a toward the outer periphery of the transport conveyor. The convex part P protrudes from the main surface of the conveyance belt 421a, so that a step S5 having the side surface of the convex part P as the end face E5 is formed. The end surface E5 is formed to face the brush 70a. Also in this example, when the brush 70a is brought into contact with the main surface of the moving conveyor belt 421a, the end surface E5 of the step S5 is also brought into contact, and the fiber waste f can be removed using the step S5.

  The fiber waste may be continuous at the step or discontinuous. When the fiber waste is discontinuous at the step, it is easy to remove the fiber waste starting from the step when the jig is brought into contact with the end face of the step. Therefore, the height of the step, the shape of the step, and the fiber accumulation state may be adjusted so that the fiber waste is discontinuous at the step. It should be noted that fiber waste is discontinuous at the level difference, where the distribution of fiber waste at the end face of the step is smaller than the fiber waste distribution at both sides of the end face (the fiber waste distribution is coarse. Say state. For example, fiber scraps may be discontinuous when the amount per unit area of fiber scraps on the end face is, for example, 50% or less of the amount per unit area of fiber scraps on both sides of the end face. In addition, the quantity of the fiber waste per unit area can be calculated | required based on a scanning electron microscope (SEM) photograph, for example. Specifically, in the SEM photograph, the projected area of the fiber scraps on the end face in the range of a predetermined area is obtained, and the area ratio of the fiber scraps per unit area is calculated. Similarly, the area ratio per unit area of the fiber waste in the regions on both sides sandwiching the end face is calculated. Then, the former ratio (%) may be calculated when the latter area ratio is 100%.

  The step may be provided along a direction perpendicular to the moving direction of the conveying belt (over the entire vertical direction), or may be provided in a region where fiber waste remains. On the conveyor belt, fibers deposited mainly in a wider area than the base material become fiber scraps. Therefore, the fiber waste remains on the main surface of the transport belt outside the end of the base material in the direction perpendicular to the moving direction of the transport belt. From such a viewpoint, it is only necessary to form steps at both ends in the direction perpendicular to the moving direction of the conveyor belt. Since almost no fiber waste is attached to the central portion in the direction perpendicular to the moving direction of the conveyor belt, it is not necessary to provide a step in particular, but a step may be formed in the central portion.

  The central portion in the direction perpendicular to the moving direction of the transport belt is a region including the center in the direction perpendicular to the moving direction of the transport belt, and preferably refers to a region inside the above-described both end portions.

8 to 10 are schematic perspective views for explaining a state of a step in a direction perpendicular to the moving direction of the conveyor belt.
In FIG. 8, the conveyance belt 521a has a step S6 having an end surface E6, and the end surface E6 faces a jig (not shown). In the illustrated example, the step S6 is formed in the entire vertical direction so as to cross the main surface of the conveyance belt 521a along the direction perpendicular to the moving direction B of the conveyance belt 521a.

  In the transport belt 621a shown in FIG. 9, the step S7 is formed at both end portions in the direction perpendicular to the moving direction B of the transport belt 621a, and no step is formed in the central portion in the vertical direction. The step S7 includes an end face E7 that faces a jig (not shown).

  In FIG. 10, the conveyance belt 721a has a step S8 having an end surface E8 facing a jig (not shown). The step S8 is formed as a whole across the conveyor belt 721a along a direction perpendicular to the moving direction B of the conveyor belt 721a. The height of the step S8 is lower at the center in the direction perpendicular to the moving direction B, and the height of the step S8 is higher at both ends than the height of the step S8 at the center. .

  8 to 10, the fiber waste f is attached to the main surface of the conveyor belt at both ends in the direction perpendicular to the moving direction of the conveyor belt. At the step of the conveyor belt, there is almost no fiber waste f on the end face, and the fiber waste f is discontinuous. As described above, since the step is formed at least in the region where the fiber scrap is adhered, the jig can be brought into contact with the end face of the step to scrape the fiber scrap. Further, since the fiber waste f is discontinuous at the level difference, the fiber waste f can be easily removed from the level difference.

  The maximum height of the step is preferably 0.1 mm or more, and more preferably 0.5 mm or more. The maximum height of the step is, for example, 5 mm or less. By forming the step so that the maximum height falls within such a range, it becomes easy to remove fiber waste.

  When the maximum height of the step becomes large, it becomes easy to remove fiber waste, but when the height of the step in the region where the base material is placed becomes large, the fiber deposition state on the nonwoven fabric varies. Therefore, in the central part in the direction perpendicular to the moving direction of the conveyor belt, no step is formed, or even when a step is formed, the height of the step in the central part is higher than the height of both ends in the direction perpendicular to the moving direction. It is preferable to reduce the size. The height of the step in the central portion is, for example, 0.05 mm or less, and preferably 0.01 mm or less or 0.005 mm or less.

What is necessary is just to form a level | step difference so that an end surface may face the moving direction of a conveyance belt. When viewed from the side surface of the conveyance belt, an angle formed between the end surface of the step and the main surface of the conveyance belt on the downstream side of the end surface in the movement direction of the conveyance belt is, for example, 70 to 140 °, It is preferable that it is 80-120 degrees.
Further, the step may be formed along a direction perpendicular to the moving direction of the conveying belt when the conveying belt is viewed from above, or may be formed obliquely with respect to the vertical direction.

  In the annular conveying belt, the step may be formed at least at one place, and may be formed at two or more places. When forming a level | step difference in two or more places along the moving direction of a conveyance belt, it becomes still easier to remove fiber waste. In this case, the maximum height of the step in at least one place may be different from the maximum height of the step in other places. When the end faces of the step (end faces facing the jig) are on the same plane, the step is formed at one place.

The jig is not limited to a brush as long as it can contact the main surface of the conveyor belt and remove fiber waste. An adhesive roller or the like can also be used, and a brush and an adhesive roller may be used in combination. As a brush, you may use a roll-shaped brush as needed.
The material of the bristles of the brush is not particularly limited, but natural fibers such as plant fibers and animal fibers, chemical fibers formed of resin, and the like are preferable from the viewpoint that the conveyance belt is not easily damaged.

  When a brush is used as the jig, it is preferable to make the average wire diameter of the brush bristles smaller than the maximum height of the step (particularly, the step at both ends in the direction perpendicular to the moving direction of the transport belt). In this case, the brush bristles contact the end surface of the step or the corner of the step (the corner formed between the end surface of the step and the main surface of the transport belt on the downstream side in the moving direction of the transport belt). It becomes easy to do and can improve the removal property of fiber waste. The average wire diameter of the brush hair can be appropriately selected from the range of 1 to 300 μm, for example, and may be 1 to 80 μm or 10 to 50 μm.

  The number of jigs used in the third step (or cleaning unit) is not particularly limited, and may be one or plural. In the case of using a plurality of jigs, the jig may be arranged along a direction perpendicular to the moving direction of the transport belt, and a plurality of jigs may be arranged at intervals along the transport path of the transport belt. A jig may be arranged. Further, a plurality of (for example, a pair) jigs along a direction perpendicular to the moving direction of the transport belt may be arranged at a plurality of locations (a plurality of pairs) at intervals along the transport path of the transport belt. When the jigs are arranged at a plurality of locations along the movement path of the conveyance belt, it is possible to further improve the removal property of the fiber waste adhering to the conveyance belt.

  In the third step, since the jig is brought into contact with the main surface of the moving conveyor belt, the jig itself need not be moved, but may be moved as necessary. When the jig is moved, it is preferable to move the jig so as to face the moving direction of the conveyor belt so that the fiber waste can be removed using the step. For example, when an adhesive roller or a roll-like brush is used as a jig, it is rotated in a direction opposite to the moving direction of the conveyor belt.

Hereinafter, each process and manufacturing apparatus other than the third process of the manufacturing method according to the present invention will be described more specifically.
(First step)
The first step is not particularly limited as long as a nonwoven fabric can be formed by generating fibers and depositing the generated fibers, and a known spinning method can be employed. For example, the non-woven fabric may be formed by dissolving fiber raw materials, generating fibers by melt spinning, and depositing while cooling.

  In a preferred embodiment, the nonwoven fabric is formed by electrospinning. In this case, in the fiber forming space, fibers are generated by electrospinning, and the generated fibers are deposited on the base material supplied to the main surface of the transport belt to form a nonwoven fabric. The fiber is produced by electrospinning a raw material liquid containing the raw material of the fiber. In electrospinning, fibers are generated by applying a high voltage to a raw material liquid and discharging the charged raw material liquid from a nozzle. In the first step, a laminate is obtained in which a nonwoven fabric is laminated on a base material (specifically, the main surface of the base material opposite to the conveyor belt).

  The raw material of the fiber is not particularly limited, and various polymers that can be fiberized can be used depending on the spinning method. Examples of such a polymer include polyamide (PA), polyimide (PI), polyamideimide, polyetherimide, polyacetal, polycarbonate, polyetheretherketone, polysulfone, polyethersulfone, polyphenylene sulfide, polytetrafluoroethylene, Examples thereof include polymers such as polyarylate, polyacrylonitrile, polyvinylidene fluoride, polystyrene (PS), polyvinyl alcohol, polyvinyl acetate, polypropylene (PP), polyethylene terephthalate (PET), and polyurethane (PU). Each of these polymers includes both homopolymers and copolymers. These polymers are also suitable as raw materials when forming nonwoven fabrics by electrospinning. Moreover, you may use the precursor of these polymers as a raw material of a fiber. For example, when the fiber is composed of PI, a PI precursor such as polyamic acid may be used as a raw material. The fiber may contain one or more of these polymers. A polymer can be suitably selected according to the use of a nonwoven fabric.

The raw material liquid used in the electrospinning method usually contains a solvent in addition to the fiber raw material. The solvent is not particularly limited as long as it dissolves the fiber raw material and can be removed by volatilization or the like, and can be appropriately selected from water and an organic solvent according to the type of raw material and production conditions. As the solvent, an aprotic polar organic solvent is preferable. Examples of such a solvent include amides such as N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMAc), and N-methyl-2-pyrrolidone (NMP) (chain or cyclic amide). A sulfoxide such as dimethyl sulfoxide; These solvent may be used individually by 1 type, and may be used in combination of 2 or more type. From the viewpoint of easy dissolution of raw materials such as PS and PU and ease of electrospinning, amides such as DMAc and DMF are preferred.
A raw material liquid can contain a well-known additive as needed.

  The average fiber diameter of the fiber obtained by the first step is not particularly limited, and can be appropriately selected from a range of 10 nm to 3 μm, for example. When the fibers are nanofibers, it is particularly difficult to remove fiber waste adhering to the conveyance belt. According to the method for producing a nonwoven fabric according to the present invention, even when the fiber is a nanofiber, the fiber can be easily removed. The average fiber diameter of the nanofibers is preferably 10 to 800 nm, for example.

  The substrate on which the fibers are deposited is not particularly limited, and a resin film or the like may be used depending on the use of the nonwoven fabric, or a porous substrate such as a nonwoven fabric (second nonwoven fabric) may be used. The resin constituting the resin film or the porous substrate is not particularly limited, and examples thereof include acrylic resin, polyolefin, polyester, and PA. Cellulose can also be used for the porous substrate. Examples of polyolefin include PP and polyethylene. Examples of the polyester include PET and polybutylene terephthalate. The porous substrate may be composed of inorganic fibers such as glass fibers. The base material may contain one or more of these materials.

In the first step, the conveyor belt is operated so that the substrate is conveyed from the upstream to the downstream of the production line, and the substrate is supplied to the main surface on which the conveyor belt moves. The shape of the substrate is not particularly limited and may be a sheet shape, but is preferably a belt shape. The belt-like base material is supplied onto the main surface of the transport belt so that the length direction of the base material is along the direction in which the transport belt transports the base material.
In addition, you may prepare a raw material liquid and a base material respectively prior to a 1st process.

(Second step)
In the second step, the laminate of the base material and the nonwoven fabric formed in the first step is separated from the transport belt.
The fibers deposited in the region outside the base material remain as fiber waste on the transport belt after the laminate is separated in the second step, and the fiber waste is removed in the third step.

  In the second step, the laminate separated from the conveyor belt may be recovered as it is, and if necessary, a drying step (or heating step), an adhesive application step, a pressure bonding step, a step of laminating a protective layer, and the like. You may collect | recover, after using for. In addition, when using the sheet | seat which has a mold release property as a base material, you may peel a base material from the formed nonwoven fabric. When the manufacturing method includes these steps, the nonwoven fabric manufacturing apparatus is a unit corresponding to each step, specifically, a drying unit (or heating unit), an adhesive application unit that applies an adhesive to a substrate or a nonwoven fabric. , A pressure-bonding part for pressure-bonding a laminate including the base material and the nonwoven fabric, a protective layer laminating device, and / or a base material peeling unit.

  ADVANTAGE OF THE INVENTION According to this invention, when depositing a fiber on a conveyance belt and forming a nonwoven fabric, the fiber waste adhering to a conveyance belt can be removed easily. Therefore, it can utilize for the manufacturing method and manufacturing apparatus of various nonwoven fabrics, such as the nonwoven fabric manufacturing method using an electrospinning method.

1: base material, 2F: fiber, 2: non-woven fabric, 3: protective layer, 4: adhesive, 10: laminated non-woven fabric, 11, 21b, 31, 41: transport roller, 12: supply reel, 13, 43, 53: Motor, 21: Conveyor, 21a, 121a, 221a, 321a, 421a, 521a, 621a, 721a: Conveyor belt, 321c: Base belt, 321d: Surface belt, 22: Raw material liquid, 23: Ejector, 24: First Support: 25: Second support, 26: Voltage application device, 27: Counter electrode, 28: Pump, 29: Raw material tank, 32: Adhesive tank, 33: Nozzle, 34: Applicator, 42: Reel, 51, 52: Pressure roller, 70: Cleaning unit, 70a: Brush, A: Substrate transport direction, B: Transport belt movement direction, f: Textile waste, S1 to S8: Step, E1 to E : End face, s: gap, P: convex part, 200: manufacturing apparatus (manufacturing system), 201: base material supply part, 202: electrospinning apparatus, 203: adhesive application part, 204: protective layer laminating apparatus, 205: Crimping part 206: Collection device

Claims (10)

A method for producing a nonwoven fabric containing fibers, comprising:
A first step of generating a fiber, and depositing the generated fiber on a base material supplied to a main surface of an annular conveyance belt to form a nonwoven fabric;
A second step of separating the nonwoven fabric together with the base material from the transport belt;
A third step of removing fiber waste remaining on the conveyor belt with a jig,
The main surface of the conveyor belt has a step having an end surface facing the jig,
The step is formed at least at both ends in a direction perpendicular to the moving direction of the conveyor belt,
The manufacturing method of the nonwoven fabric which makes the main surface of the said conveyance belt, the end surface of the said level | step difference, and the said jig | tool in the said 3rd process, and removes the said fiber waste.   The maximum height of the said level | step difference is a manufacturing method of the nonwoven fabric of Claim 1 which is 0.1 mm or more. The main surface of the conveyor belt has the step in the central portion in the direction perpendicular to the moving direction of the conveyor belt,
The height of the said level | step difference in the said center part is a manufacturing method of the nonwoven fabric of Claim 1 or 2 smaller than the height of the said level | step difference in the said both ends.   The height of the said level | step difference in the said center part is a manufacturing method of the nonwoven fabric of Claim 3 which is 0.01 mm or less.   The said fiber waste is a manufacturing method of the nonwoven fabric of any one of Claims 1-4 which is discontinuous in the said level | step difference.   The said jig | tool has a brush, The manufacturing method of the nonwoven fabric of any one of Claims 1-5.   The method for producing a nonwoven fabric according to claim 6, wherein an average wire diameter of the bristles of the brush is smaller than a height of a step at the both end portions.   In the said 1st process, the manufacturing method of the nonwoven fabric of any one of Claims 1-7 which produces | generates the said fiber by electrospinning the raw material liquid containing the raw material of a fiber.   The said fiber is a manufacturing method of the nonwoven fabric of any one of Claims 1-8 which is a nanofiber. A base material supply unit for supplying the base material to the main surface of the annular conveying belt;
A spinning mechanism for generating fibers and depositing the fibers on the substrate to form a nonwoven fabric;
A jig for removing fiber waste remaining on the conveyor belt after the nonwoven fabric and the substrate are separated from the conveyor belt,
The main surface of the conveyor belt has a step having an end surface facing the jig,
The step is formed at least at both ends in a direction perpendicular to the moving direction of the conveyor belt,
The said waste fiber is a nonwoven fabric manufacturing apparatus removed by making the said jig | tool contact the main surface of the said conveyance belt, and the end surface of the said level | step difference.

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