JP2021070882A - Method for producing nonwoven fabric and apparatus for producing nonwoven fabric - Google Patents

Abstract

To provide a method for producing a nonwoven fabric which allows a loose insertion of a recess part and a protrusion part opposed to each other to be appropriately conducted when performing convexoconcave shaping.SOLUTION: A method for producing a nonwoven fabric includes supplying a fiber material between a support roll and a push-in body to perform convexoconcave shaping. On a surface of the support roll, a protrusion part and a recess part are alternately arranged along an axial direction of the support roll. The push-in body comprises a unit in which a part to be loosely inserted to which the protrusion part is loosely inserted, and a push-in part to be inserted to the recess part are alternately arranged along a width direction of the push-in body parallel to the axial direction of the support roll, and a movement mechanism allowing the unit to move in the width direction. The loose insertion is conducted by controlling a position in the width direction of the unit by the movement mechanism and performing convexoconcave shaping to the fiber material.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for producing a non-woven fabric and an apparatus for producing a non-woven fabric.

Nonwoven fabrics are often used as constituent members of absorbent articles because of their liquid permeability and good touch. Techniques for improving the physical properties of non-woven fabrics used for absorbent articles have been proposed so far.
For example, Patent Document 1 describes a shaping device provided with a pair of upper and lower stretching rolls as a device for improving the softness and smoothness of a non-woven fabric. The upper stretched roll is provided with a plurality of convex ridges at regular intervals in the roll width direction and parallel to each other along the outer peripheral surface of the roll. A concave groove is arranged between the adjacent convex ridges. The lower stretching roll is provided with a plurality of pins provided on the outer peripheral surface thereof so as to mesh with the concave groove. These pins are arranged at regular intervals in the roll width direction so as not to contact the convex ridges of the upper stretching roll, and are arranged substantially linearly at regular intervals along the outer peripheral surface. There is.

Japanese Unexamined Patent Publication No. 2016-123651

When the convex portions of the concavo-convex members arranged so as to face each other are loosely inserted into the concave portions of the other to perform the concavo-convex shaping on the fiber material as in the shaping device described in Patent Document 1, contact between the convex portions is prevented. Is required. By preferably performing loose insertion into the concave portion without bringing the convex portions into contact with each other, it is possible to satisfactorily shape the unevenness of the fiber material (fiber web, non-woven fabric, etc.), and unexpected damage (perforation) of the fiber material. It can prevent cutting).
However, the contact between the convex portions may occur due to the positional deviation of the concave-convex member in the width direction. In the width direction of the concavo-convex member, the space between the convex portions is often narrow by only a few millimeters, and if the above-mentioned positional deviation occurs during the concavo-convex shaping process, it is difficult to correct it. In particular, when the concavo-convex members facing each other have different materials and structures (for example, one of which has a structure in which a plurality of elements are assembled), the above-mentioned positional deviation is likely to occur.
Therefore, in the shaping process, it is required to control the position of the uneven member in the width direction with high accuracy in millimeters.

In view of the above points, the present invention relates to a non-woven fabric manufacturing method and a non-woven fabric manufacturing apparatus capable of suitably performing loose insertion between opposing concave-convex members when performing uneven-convex shaping.

The present invention is a method for producing a non-woven fabric in which a fiber material is supplied between a support roll and a push-in body to form unevenness, and on the surface of the support roll, convex portions and concave portions are formed on the shaft of the support roll. The push-in body is arranged alternately along the direction, and the push-in body has a push-in portion in which the convex portion is loosely inserted and the push-in portion loosely inserted in the concave portion is parallel to the axial direction of the support roll. The unit has units arranged alternately along the width direction and a movement mechanism that enables the unit to move in the width direction, and the movement mechanism controls the position of the unit in the width direction to control the position of the unit in the width direction. Provided is a method for producing a non-woven fabric, which performs loose insertion and embodies unevenness on the fiber material.

Further, the present invention is an apparatus for producing a non-woven fabric in which a fiber material is supplied between a support roll and a push-in body to form unevenness, and on the surface of the support roll, convex portions and concave portions are formed on the support roll. The push-in body is arranged alternately along the axial direction of the support roll, and the push-in portion in which the free-insertion portion in which the convex portion is loosely inserted and the push-in portion loosely inserted in the concave portion are parallel to the axial direction of the support roll. It has units arranged alternately along the width direction of the body and a moving mechanism that enables the unit to move in the width direction, and the position of the unit in the width direction is controlled by the moving mechanism. Provided is a non-woven fabric manufacturing apparatus for performing the loose insertion and performing unevenness shaping on the fiber material.

According to the method for manufacturing a non-woven fabric and the manufacturing apparatus of the present invention, it is possible to preferably execute loose insertion between opposing uneven members when performing uneven shaping.

It is sectional drawing which shows typically one preferable embodiment of the nonwoven fabric manufacturing apparatus of this invention. It is a partial perspective view which showed a preferable example of the support roll surface of the manufacturing apparatus shown in FIG. It is a partial cross-sectional view of the support roll shown in FIG. It is a partial cross-sectional view which showed the arrangement relationship between the convex part and the concave part of the support roll, and the push-in part of a push-in body. It is sectional drawing which showed a preferable example of a spline as a moving mechanism. It should be noted that the push-in portion and the idle insertion portion of the unit are not shown. It is the schematic perspective view which showed the preferable example of the push-in body. It is the schematic perspective view which showed another preferable example of the push-in body. FIG. 5 is a schematic perspective view showing yet another example of a pusher with corresponding support rolls and fibrous materials.

Hereinafter, a manufacturing apparatus for carrying out the method for manufacturing a nonwoven fabric of the present invention will be described based on a preferred embodiment thereof with reference to the drawings.

As shown in FIG. 1, the non-woven fabric manufacturing apparatus 1 of the present embodiment has a support roll 10 and a push-in body 20 arranged to face each other. A fiber material (not shown) is supplied between the support roll 10 and the push-in body 20 to form unevenness. The term "fiber material" as used herein refers to an aggregate of fibers formed into a sheet, and includes, for example, a non-woven fabric and a fiber web. The "nonwoven fabric" refers to fibers in an aggregate of fibers that are bonded to each other at their intersections or that are not easily separated by entanglement of the fibers. For example, fibers are bonded to each other by heat fusion or adhesive at the intersection (thermal bond non-woven fabric, resin bond non-woven fabric, etc.), or fibers are entangled with each other by the pressure of water flow (spun lace non-woven fabric, etc.). including. The "fiber web" refers to a material in a state before the fibers are bonded to each other in an aggregate of fibers, and is a material before being made into a non-woven fabric.

On the surface 10S of the support roll 10, convex portions 11 and concave portions 12 are alternately arranged along the axial direction X1 of the support roll 10. As a result, the support roll 10 is a concavo-convex member having a concavo-convex surface along the axial direction X1. The support roll 10 may have a drum shape, for example. The drum shape means a hollow cylindrical shape. In the circumferential direction of the surface 10S of the support roll 10, the convex portions 11 and the concave portions 12 may be arranged alternately, or the convex portions 11 may be continuously arranged. Continuous means a state of being connected without interruption.
Further, as shown in FIGS. 2 and 3, the convex portions 11 are arranged at equal intervals in the axial direction X1 and the circumferential direction Y of the surface 10S of the support roll 10, and the concave portions 12 surround the convex portions 11 vertically and horizontally. It may be arranged in a grid-like continuous form on the surface 10S of the support roll 10.
The support roll 10 preferably has a plurality of openings penetrating from the front surface 10S to the back surface between the convex portions 11. By having the holes, the wind easily blows through the support roll 10, and it is possible to prevent the fiber material from being disturbed or scattered. As a result, the unevenness of the fiber material can be suppressed and homogenized, and the shaping that suppresses the hardening of the fiber material becomes possible. Further, when the wind blows through the support roll 10, the fiber material can be easily pushed from the top of the convex portion 11 to the support roll 10, and the uneven shape having a height can be made clearer and efficiently shaped. Further, the orientation of the fiber material along the wall surface of the convex portion 11 becomes more remarkable due to the wind blow through. As a result, a bulky and soft non-woven fabric can be efficiently produced.

It is preferable that all the wall surfaces of the convex portions 11 are perpendicular to the surface 10S of the support roll 10. By using the support roll 10 in which the wall surface of the convex portion 11 is perpendicular to the surface 10S, it is possible to manufacture a non-woven fabric that is bulkier and softer than the conventional one.
"All the wall surfaces of the convex portions 11 are perpendicular to the surface 10S of the support roll 10" means that they are perpendicular to the surface 10S of the support roll 10 at any position on the wall surface. For example, when the convex portion 11 is a prism with angles such as a prism, it means that each surface sandwiched between the corners forming the wall surface is perpendicular to the surface 10S of the support roll 10. When the convex portion 11 is a columnar body having no corners such as a cylinder, it means that it is perpendicular to the surface 10S of the support roll 10 at any point of the curved surface constituting the wall surface.
"Vertical to the surface 10S of the support roll 10" means that the direction in which the wall surface is erected is perpendicular to the surface 10S of the support roll 10. For example, as shown in FIG. 3, when the surface 10S of the support roll 10 is an arcuate curved surface that is convex outward, the top of the wall surface from the root on the support roll 10 side at the side-viewed end surface of the support roll 10. It is said that the angle θ formed by the outer line to the side and the tangent line J with respect to the arc of the surface 10S at the width center point of the end surface of the convex portion 11 is perpendicular. In the present invention, it is preferable that the wall surface is in the "vertical" state as defined below for all the cross-sections or side-viewed end faces at any position of the convex portion 11.
“Vertical” means 88 ° or more and 92 ° or less with respect to the surface 10S of the support roll 10, preferably 89 ° or more, more preferably 89.5 ° or more, and preferably 91 °. Hereinafter, it is more preferably 90.5 ° or less.
The angle of the wall surface of the support roll 10 with respect to the surface 10S can be measured using MICURA manufactured by Tokyo Seimitsu Co., Ltd. The position of the surface 10S (plane or curved surface) of the support roll 10 is measured from 5 points other than the opening of the recess 12 in the direction orthogonal to the wall surface to be measured, and further, from 3 points in the height direction of the wall surface to the wall surface. The position is measured and the angle is derived from the positional relationship between the two.

The height of the convex portion 11 is preferably 1.5 times or more the maximum diameter of the convex portion 11 from the viewpoint of improving the cushioning property, and twice the maximum diameter of the convex portion 11 from the viewpoint of further improving the cushioning property. The above is more preferable, and from the viewpoint of further improving the cushioning property, it is further preferable to be 3 times or more the maximum diameter of the convex portion 11.
Further, the height of the convex portion 11 is preferably 10 times or less the maximum diameter of the convex portion 11 from the viewpoint of stabilizing the shape after shaping, and the convex portion 11 from the viewpoint of further stabilizing the shape after shaping. It is more preferably 9 times or less the maximum diameter of the convex portion 11, and further preferably 8 times or less the maximum diameter of the convex portion 11 from the viewpoint of further stabilizing the shape after shaping.
The "maximum diameter" of the convex portion 11 means the maximum length of the convex portion 11 in the axial direction X1 and the circumferential direction Y of the surface 10S of the support roll 10.

The top of the convex portion 11 is preferably roughened. As a result, it is possible to increase the hookability to the fibers, preferably to increase the amount of fibers remaining on the top, and to prevent the fibers from being partially thinned when pressed into the fiber material. In addition, it is possible to produce a non-woven fabric having few spots by roughening the surface. The roughening may be applied only to a part of the top, may be applied to the entire top, or may be applied to a part of the upper part of the wall surface from the top. Considering the hookability to the fibers and the ease with which the fibers follow the wall surface, it is preferable that the entire top is roughened, and it is more preferable that the edges of the top are also roughened. Further, considering the ease of peeling after making the non-woven fabric, it is preferable that only the top surface is roughened and the wall surface is not roughened.
As a method of roughening the top surface, various methods applied to the support roll 10 of this type, such as sandblasting, can be used.

The push-in body 20 is a unit in which the play-inserted portion 23 into which the above-mentioned convex portion 11 is loosely inserted and the push-in portion 22 loosely inserted into the above-mentioned concave portion 12 are alternately arranged along the width direction X2 of the push-in body 20. Has 21. The width direction X2 of the pushing body 20 is parallel to the axial direction X1 of the support roll 10.
The idle insertion portion 23 is a space portion in which the convex portion 11 of the support roll 10 is loosely inserted. Therefore, the pushing body 20 is a concavo-convex member having a concavo-convex surface in the width direction X2 between the idle insertion portion 23 and the pushing portion 22. The above-mentioned "play insertion" means that the insertion is performed with play. The convex portion 11 of the support roll 10 is inserted into the idle insertion portion 23 of the unit 21 of the pushing body 20 while leaving a gap. The pushing portion 22 of the unit 21 of the pushing body 20 is inserted into the recess 12 of the support roll 10 while leaving a gap.

In the pushing body 20, the pushing portion 22 and the idle insertion portion 23 of the unit 21 are preferably arranged so as to correspond to the concave portion 12 and the convex portion 11 in the circumferential direction Y of the support roll 10. In this case, the pushing portion 22 and the idle insertion portion 23 of the unit 21 may be arranged so as to correspond to all the concave portions 12 and the convex portions 11 in the circumferential direction Y of the support roll 10, and only partially correspond to them. It may be arranged. For example, the pushing portion 22 of the pushing body 20 may not be arranged with respect to a part of the recess 12 in the circumferential direction Y of the support roll 10.

The push-in body 20 has a movement mechanism (not shown) that allows the unit 21 to move in the width direction. Even if the convex portion 11 of the support roll 10 and the pushing portion 22 of the pushing body 20 come into contact with each other due to the positional deviation of the support roll 10 or thermal expansion, this moving mechanism utilizes the contact force to form a unit of the pushing body 20. 21 is a structure that can automatically move in the width direction X2. For example, the unit 21 is incorporated so as to be movable to the left and right in the width direction X2 by lubrication with respect to the rail member extending in the width direction X2, or the unit 21 is placed between the rail member and the unit 21 in the width direction X2 left and right. Examples thereof include a structure in which a trolley member that allows the vehicle to move is interposed. As a result, the pushing body 20 can control the position in the width direction X2.

The arrangement relationship between the convex portion 11 and the concave portion 12 of the support roll 10 and the pushing portion 22 of the pushing body 20 is shown, for example, as shown in FIG. A pushing portion 22 having a width W is loosely inserted with respect to a width D0 between the convex portions 11 and 11 (recessed portion 12) of the support roll 10. At this time, the clearance D1 between one side surface of the push-in portion 22 and the side surface of the convex portion 11 and the distance D2 between the other side surface of the push-in portion 22 and the side surface of the convex portion 11 are the clearances. These intervals D0, width W, and tolerance tolerances D1 and D2 are all dimensions in millimeters. For example, if the width D0 between the convex portions 11 and 11 is 4 mm and the width W of the pushing portion 22 is 2 mm, the clearance is 1 mm on one side. It is necessary to allow the pushing portion 22 to be loosely inserted within this margin of only 1 mm. It is preferable to control the position of this evenly over the entire width (for example, 2 to 4 m) of the support roll 10 and the push-in body 20.
On the other hand, in the non-woven fabric manufacturing apparatus of the present embodiment, the above-mentioned position control can be automatically executed by the moving mechanism during the unevenness shaping, and can be executed in units of 21 units. In particular, the longer the width of the support roll 10 and the push-in body 20, the higher the effect of position control of the convex portion 11 and the push-in portion 22. For example, in the present embodiment, it is possible to control the position in which the convex portion 11 and the pushing portion 22 are loosely inserted with a clearance of about 1 mm over a width of 2 to 4 m (2000 mm to 4000 mm) of the member.

In the non-woven fabric manufacturing apparatus 1 of the present embodiment, even if the support roll 10 is moved or thermally expanded, the position of the unit 21 of the pushing body 20 in the width direction X2 is automatically adjusted by the moving mechanism described above. It is modified and controlled. As a result, the position of the idle insertion portion 23 with respect to the convex portion 11 is corrected, and the free insertion of the convex portion 11 into the idle insertion portion 23 can be preferably executed. At the same time, the position of the pushing portion 22 with respect to the recess 12 is corrected, and the pushing portion 22 can be suitably inserted into the recess 12. As a result, unevenness shaping on the fiber material can be satisfactorily carried out. In addition, it is possible to prevent unexpected damage (perforation or cutting) of the fiber material. That is, it is possible to efficiently produce a high-quality non-woven fabric having a concave-convex shape.

As shown in FIG. 1, the non-woven fabric manufacturing apparatus 1 of the present embodiment preferably has a plurality of units 21. Further, it is preferable that each unit 21 is provided with the above-mentioned moving mechanism. As a result, each unit 21 can be individually moved in the width direction X2 of the pushing body 20. As a result, the pusher 20 can be subdivided and the position in the width direction can be controlled to a higher degree with respect to the total length of the support roll 10 in the axial direction X1 where the movement or thermal expansion has occurred. For example, even if the thermal expansion of the support roll 10 occurs non-uniformly in the axial direction X1, the position can be controlled for each unit 21 according to the non-uniform thermal expansion.

The method for producing a non-woven fabric of the present embodiment is performed using the above-mentioned non-woven fabric manufacturing apparatus 1. More specifically, it can be carried out as follows. First, the fiber material is supplied between the support roll 10 and the push-in body 20 while rotating the support roll 10 in the machine flow direction (MD, Machine Direction). The above-mentioned free insertion is performed between the support roll 10 and the push-in body 20 to shape the unevenness of the fiber material. At that time, if there is contact between the convex portion 11 and the pushing portion 22, the position of the unit 21 in the width direction X2 is corrected and controlled by the above-mentioned moving mechanism. As a result, the above-mentioned idle insertion can be suitably executed without stopping the operation of the manufacturing apparatus 1 during the unevenness shaping process, and the unevenness shaping of the fiber material can be performed satisfactorily and continuously. As a result, it is possible to continuously produce a high-quality non-woven fabric having an uneven shape with good yield and efficiency. From the viewpoint of easier position control, as described above, the pushing body 20 preferably has a plurality of units 21, and it is more preferable that each unit 21 is provided with the above-mentioned moving mechanism.

As the fiber material used in the method for producing a non-woven fabric of the present embodiment, various materials that can be formed into irregularities can be used without particular limitation. For example, the above-mentioned non-woven fabric, fiber web, and the like can be mentioned. The non-woven fabric referred to here is a sheet-shaped raw material non-woven fabric before the unevenness is formed. As the raw material non-woven fabric, various non-woven fabrics usually used in the field of non-woven fabric can be adopted without particular limitation, and can be produced by various commonly used methods. The fiber web is a sheet-like fiber aggregate in which fibers are not bonded at intersections, and can be produced by various commonly used methods. For example, the carding method and the like can be mentioned. In the case of a fiber web, a step of joining the fibers at an intersection is carried out after shaping the unevenness. In this bonding step, various commonly used methods can be adopted, and examples thereof include chemical bonding, physical bonding, thermal bonding (fusion), and mechanical bonding. For thermal bonding, the fiber web preferably contains thermoplastic fibers.

In the method for producing a non-woven fabric of the present embodiment, it is preferable to have a heating step in which the support roll 10 for shaping the unevenness of the fiber material is heated. That is, it is preferable that the nonwoven fabric manufacturing apparatus 1 has a heating apparatus (not shown) for heating the support roll 10. By heating the support roll 10, the fiber material supported by the support roll 10 is also heated at the same time, and a non-woven fabric having irregularities shaped can be produced more efficiently. The term "supported by the support roll 10" means that the fiber material is broadly included from a state in which the fiber material is simply placed on the support roll 10 to a state in which the fiber material is formed into unevenness and follows the uneven shape of the support roll 10. is there.

When there is a heating step for the support roll 10, specifically, the following treatment is performed.
For example, when the fiber material is a fiber web, first, the fiber web is placed on the support roll 10 and the pushing body 20 is pressed while rotating the fiber web, and the above-mentioned free insertion is performed to shape the fiber web into unevenness. The unevenly shaped fiber web follows the uneven shape of the support roll 10. Next, the fibers of the fiber webs along the uneven shape of the support roll are fused to each other by the heating step. As a result, the support roll 10 makes the non-woven fabric as it is in a state where the uneven shape of the fiber web is stably held, and the non-woven fabric having the uneven shape can be manufactured more efficiently.
Further, for example, when the fiber material is a non-woven fabric (raw material non-woven fabric), first, the non-woven fabric is placed on the support roll 10 and rotated while being heat-treated immediately before shaping. As a result, the fusion force between the fused fibers of the non-woven fabric can be relaxed. After weakening the fiber fusion force, the non-woven fabric is placed on the support roll 10 and the pushing body 20 is pressed while further rotating, and the above-mentioned loose insertion is performed to shape the non-woven fabric into unevenness. As a result, heating of the non-woven fabric (raw material non-woven fabric) and uneven shaping can be continuously performed on the support roll 10, and the non-woven fabric having the uneven shape can be produced more efficiently.

In any case, the heating step is preferably a step of blowing hot air toward the support roll 10 that supports the fiber material. That is, it is preferable that the heating device included in the above-mentioned non-woven fabric manufacturing device 1 is arranged at a position where hot air is blown toward the support roll that supports the fiber material. By blowing hot air, the hot air penetrates the fiber material and is heated relatively evenly in the thickness direction. The temperature, wind speed, and the like of the hot air are all appropriately selected depending on the type of fiber of the fiber material, the basis weight, and the like. Further, it is preferable to use hot air by heating air from the viewpoint of ease of handling and cost.

When there is such a heating step, the support roll 10 is heated and thermally expanded, and the distance between the convex portions 11 arranged in the rotation axis direction may be extended. In this case, in the conventional shaping device, the pushing portion 22 and the convex portion 11 may come into strong contact with each other during the uneven shaping, and one or both of them may be damaged.
However, in the non-woven fabric manufacturing apparatus 1 and the manufacturing method of the present embodiment, the pushing portion 22 and the convex portion 11 do not strongly contact the position of the unit 21 of the pushing body 20 in the width direction X2 due to the action of the moving mechanism described above. Can be moved automatically. As a result, the above-mentioned loose insertion can be suitably performed, and the uneven shaping of the fiber material can be performed satisfactorily and continuously.
In particular, in a situation where the operation must be temporarily stopped for some reason while heating the support roll 10, it is possible to accelerate the return to continuous production, which is more effective for efficient continuous production of the unevenly shaped nonwoven fabric. Is. This is because the non-woven fabric manufacturing apparatus and manufacturing method of the present embodiment can solve the conventional problem in the uneven shaping involving the heating step.
That is, when the uneven shaping is temporarily stopped, it is difficult for the heating device to temporarily stop due to its nature, and a part of the support roll 10 whose rotation has stopped is exposed to hot air. In this case, there are portions in the support roll 10 having different degrees of thermal expansion, and the degree of misalignment of the positional relationship between the convex portion 10 and the pushing portion 22 is also different. In such a situation, in the conventional shaping device, the above-mentioned free insertion between the support roll 10 and the pushing body 20 must be removed until the difference in the thermal expansion dimensions of the support roll 10 is within a certain range. In this case, conventionally, it takes time to properly restart the operation, and a manufacturing loss occurs.
On the other hand, in the non-woven fabric manufacturing apparatus and manufacturing method of the present embodiment, the time until the operation is restarted is shortened in response to the positional deviation by controlling the position of the unit 21 of the pushing body 10 by the action of the moving mechanism described above. be able to. As a result, the continuous production efficiency of the non-woven fabric having the uneven shape can be improved.

Further, the non-woven fabric manufacturing apparatus 1 of the present embodiment may have a smoothing roll (not shown) in contact with the outer peripheral surface of the support roll 10 on the downstream side of the push-in body 20. The smoothing roll preferably has a heating mechanism on the roll surface. As a result, other fibrous materials can be accurately heat-sealed and bonded by the smoothing roll while keeping the non-woven fabric shaped by the unevenness along the uneven shape of the support roll 10. That is, in the heat fusion bonding by the smoothing roll, the support roll 10 preferably retains the uneven shape of the non-woven fabric, and a laminated non-woven fabric having a two-layer structure having a good uneven shape can be produced. In addition, since the non-woven fabric having the uneven shape is heat-sealed to be bonded to other fiber materials at the portion supported by the convex portion 11 of the support roll 10, unnecessary heat-sealing is suppressed and the non-woven fabric is soft. It can be made easier to hold.
The above-mentioned "downstream side" means a position on the rear side of a certain point in the machine flow direction (MD) in the manufacturing apparatus. As for the manufacturing method, it means the back side of a certain process in the machine flow direction (MD). Further, the "smoothing roll" has no unevenness that enables loose insertion between the convex portion 11 and the concave portion 12 of the opposite support roll 10, and enables uniform pressing on the convex portion 11. It means that the peripheral surface of the roll is flat to some extent.

In the above manufacturing method, for example, the following steps may be carried out.
First, the support roll 10 sucks the fiber material toward the inside of the support roll 10. In the sucked state, the above-mentioned loose insertion between the support roll 10 and the pushing body 20 is performed to shape the fiber material into unevenness.
Next, the fiber material is supplied onto the fiber material in a state where the fiber material is aligned with the uneven shape of the support roll 10 by the suction, and the fiber material and the other fiber material are laminated in a laminated state. It is sandwiched between the support roll and the smoothing roll and conveyed. At the same time, the smoothing roll is heated to fuse the fiber material with the other fiber material. This makes it possible to manufacture a laminated non-woven fabric having a two-layer structure having a good uneven shape.

Next, a preferable specific example of the structure of the push-in body 20 will be described.
The push-in body 20 shown in FIG. 1 has a roll shape and is rotatable in the roll circumferential direction. The pushing body 20 has a rotating shaft 31. A plurality of units 21 are arranged on the outer peripheral surface of the rotating shaft 31 in the width direction (axial direction of the rotating shaft 31) X2. As described above, each unit 21 alternately has the pushing portion 22 and the idle insertion portion 23 along the width direction X2 of the pushing body 20.

In the pushing body 20, each unit 21 is preferably formed of a tubular body through which the rotating shaft 31 is inserted. That is, it is preferable that each unit 21 has an annular shape that covers the entire circumference of the rotating shaft 31 in the peripheral surface direction. As a result, while the pushing body 20 rotates according to the rotation of the support roll 10, the force of this rotation causes the convex portion 11 to be loosely inserted into the loosened portion 23 and the pushing portion 22 to be loosely inserted into the concave portion 12. It is done continuously.

In the roll-shaped pushing body 20, the pushing portion 22 and the free insertion portion 23 may be continuously arranged in the circumferential direction of the rotating shaft 31, or may be alternately arranged in the circumferential direction of the rotating shaft 31. .. In the case of continuous arrangement, there is a structure in which the adjacent push-in portion 22 and the idle insertion portion 23 run in parallel over the entire circumferential direction of the rotation shaft 31. Examples of the alternating arrangement include a structure in which the pushing portions 22 are arranged in a grid pattern and the portion surrounded by the pushing portions 22 is the idle insertion portion 23. In this case, the idle insertion portion 23 is arranged in a grid pattern. Further, in the case of alternating arrangement, the idle insertion portion 23 is continuously arranged in the circumferential direction of the rotating shaft 31, while the pushing portion 22 is intermittently arranged in the circumferential direction of the rotating shaft 31, and the intermittent portion is idled. Examples thereof include a structure formed in the insertion portion 23.
The arrangement of the pushing portion 22 and the idle insertion portion 23 in the width direction X2 (axial direction of the rotating shaft 31) and the circumferential direction of the rotating shaft 31 depends on the arrangement pattern of the convex portion 11 and the concave portion 12 in the support roll 10. Further, it can be appropriately set according to the required uneven shape.

In the roll-shaped push-in body 20, examples of the above-mentioned moving mechanism include those shown in FIG. This moving mechanism has a concave portion that is slidable on the inner peripheral surface of the unit 21 with respect to the convex portion 32 arranged in the axial direction of the outer peripheral surface of the rotating shaft 31 (width direction X2 of the pushing body 20). It has a structure arranged by 25. It is a so-called spline structure having a spline shaft (rotating shaft 31) and a spline hole (concave portion 25). In this structure, the convex portion 32 serves as a guide rail for the concave portion 25, and each unit 21 can move in the axial direction of the rotating shaft 31. The cross-sectional shape of the ridge portion 32 is not particularly limited, but a trapezoidal shape, a quadrangle, or a deformation thereof, in which the ridge portion 25 is easy to slide and easily transmit a rotational force, is preferable. That is, the cross-sectional shape of the concave portion 25 is preferably a shape that matches the cross-sectional shape of the convex portion 32 so as to be slidable with respect to the convex portion 32. Further, in this moving mechanism, since the convex portion 32 and the concave portion 25 are in contact with each other on the side surface, the rotational force of the rotating shaft 31 is transmitted from the convex portion 32 to the concave portion 25 and rotates. The unit 21 can be rotated with the rotation of the shaft 31.

Examples of the moving mechanism when the pushing body 20 is in the shape of a roll include a ball bush, a non-lubricated bush, or a combination thereof, in addition to the spline as described above. Of these, splines are preferable from the viewpoint of torque transmission. Specific examples of splines include square splines, involute splines, standard splines, ball splines and the like.
As specific examples of the commercially available moving mechanism used in the present invention, the ball bush is ST70B (trade name, manufactured by THK Co., Ltd.), the oil-free bush is SPB-709080 (trade name, manufactured by Oiles Industries, Ltd.), and the standard spline is MZ70. (Product name, manufactured by Maruzen Seiki Co., Ltd.), SLS70 (trade name, manufactured by THK Co., Ltd.), etc. for the ball spline.

The push-in body 20 may have the same material and structure as the support roll 10, or may have a different material and structure. Even if the push-in body 20 has a different material and structure (structural difference between a ring roll and a drum roll, etc.), the position of the push-in portion 22 of the push-in body 20 is controlled by the action of the above-mentioned moving mechanism. As a result, the convex portion 11 is preferably loosely inserted into the idle insertion portion 23, and the push-in portion 23 is preferably loosely inserted into the concave portion 12. This point also applies to the push-in bodies 20A and 20B shown below.

Next, another preferable specific example of the push-in body 20 will be described with reference to FIGS. 6 to 8.

FIG. 6 shows a roll-shaped push-in body 20A.
The pushing body 20A has a rotating shaft 31 and a plurality of units 21A arranged on the outer peripheral surface of the rotating shaft 31 in the width direction (axial direction of the rotating shaft 31) X2. Each unit 21A has a push-in portion 22A arranged in a grid pattern and a playable insertion portion 23A surrounded by the push-in portion 22. The idle insertion portion 23A is arranged in a grid pattern. In the illustrated example, the number of units is 4, but the number of units is not limited to 4. Each unit 21A is provided with the above-mentioned moving mechanism that can move in the width direction X2.

As the pushing portion 22A of the pushing body 20A, for example, the pushing portion 22A continuous in the circumferential direction may be disk-shaped, and the pushing portion 22A continuous in the width direction X2 may be linear, or all may be linear. Good. However, the shape and arrangement of the double push-in portion 22A are not limited to these. The shape and arrangement of both push-in portions 22A should be variously set according to the shape of the recess 12 of the support roll 10 and the thickness and basis weight of the fiber material to be shaped, as long as the fiber material can be pushed in appropriately. Can be done.

The push-in body 20A shown in FIG. 6 and the support roll 10 shown in FIGS. 1 to 3 rotate in the machine flow direction (MD) while maintaining a loosely inserted state so that the convex portion 11 and the push-in portion 22A do not come into contact with each other. .. Therefore, the width of the pushing portion 22A is smaller than the distance between the convex portions 11 (width of the concave portion 12) in both the axial direction X1 (width direction X2) and the circumferential direction Y.

Next, FIG. 7 shows a roll-shaped push-in body 20B.
The push-in body 20B is formed by laminating a plurality of thin plate-shaped ring rolls in the width direction X2 on the outer peripheral surface of the rotation shaft 31. The ring roll is divided into a predetermined number of sheets, and a plurality of units 21B are arranged in the width direction (axial direction of the rotation shaft 31) X2. Each unit 21B alternately has a push-in portion 22B made of the ring roll and a groove-shaped idle insertion portion 23B between the push-in portions 22B at equal intervals in the width direction X2. The number of units 21B can be set as appropriate. In the unit 21B, the pushing portions 22B are arranged at equal intervals in the roll axis direction corresponding to the recesses 12 of the support roll 10. As a result, the pushing portion 22B is loosely arranged in the recess 12 between the convex portions 11 and 11 in the axial direction X1 of the support roll 10 shown in FIGS. 1 to 3. Further, in the unit 21B, the convex portion 11 of the support roll 10 is loosely arranged in the idle insertion portion 23B.

In the push-in body 20B, as described above, thin plate-shaped ring rolls are laminated in the width direction X2. Therefore, there is a possibility that the push-in body 20B and the support roll 10 may be displaced due to an error in the thickness of the ring roll, warpage, mixing of dust between the ring rolls, and the like. Even in this case, by using a plurality of units 21B, the width of one unit is reduced, and the accumulation of positional deviation due to thickness error, warpage, and mixing of dust between ring rolls is not increased. Therefore, with respect to the mutual position of the units 21B, the position of the unit 21B is controlled by the action of the above-mentioned moving mechanism, and the position of the pushing portion 22B made of the ring roll is preferably corrected. As a result, the convex portion 11 is preferably loosely inserted into the idle insertion portion 23B and the push-in portion 23B is preferably loosely inserted into the concave portion 12. This is more effective when the push-in body 20B has a long width (for example, more than 300 mm) in the width direction X2. For example, when the width of the production machine (= push-in body 20 and support roll 10) is 3 m and the pitch of the convex portions 11 in the axial direction X1 of the support roll 10 is 6 mm, 500 ring rolls are laminated. In this case, it is difficult to reduce the thickness error and warpage of all 500 ring rolls so that each ring roll is loosely inserted into the recess 12 within the pitch of 6 mm, and even if it is possible, it takes time. This will result in a huge cost increase. On the other hand, according to the non-woven fabric manufacturing apparatus 1 and the manufacturing method of the present embodiment, the above-mentioned loose insertion is suitably carried out by the action of the unit (division) and the moving mechanism, and the uneven shape is formed with good quality. Non-woven fabric can be efficiently manufactured.
From this point of view, it is more preferable to have a plurality of units 21B provided with a moving mechanism. As a result, even if there is a cumulative error on the long support roll 10 side, the position of the pushing body 20B can be controlled for each unit 21B made of the ring roll, and the contact (interference) between the convex portion 11 and the pushing portion 22B. ) Can be preferably avoided. Further, since the ring roll has a thin plate shape, the thermal expansion of the unit 21B unit tends to be smaller than that of the support roll 11, which is extremely small. Therefore, even if the long-width support roll 10 thermally expands, the position correction of the ring roll is controlled for each unit 21B, and contact (interference) between the convex portion 11 and the pushing portion 22B can be suitably avoided.

FIG. 8 shows the configuration of a pair of tooth groove rolls to be shaped together with the fiber material 50 to be processed. The tooth groove roll has a support roll 10D and a push-in body (push-in roll) 20D. As the support roll 10D, a concavo-convex roll having tooth grooves cut at equal intervals in the roll circumferential direction of the rotating shaft 13 and its outer peripheral surface is used. The tooth portion is the convex portion 11, and the groove portion is the concave portion 12. The pushing body 20D is a concavo-convex roll, and has a rotating shaft 31 and a plurality of units 21D arranged on the outer peripheral surface of the rotating shaft 31 in the width direction X2 (axial direction of the rotating shaft). Each unit 21D has a moving mechanism (not shown) capable of moving the unit 21D in the width direction X2 (axial direction of the rotating shaft) between the unit 21D and the rotating shaft 31.
Each unit 21D is an uneven roll in which a tooth groove is cut in the width direction X2 of the pushing body 20D, the tooth portion is the pushing portion 22D, and the groove portion is the idle insertion portion 23D. The pushing portion 22D is arranged in a convex shape in the circumferential direction, and the idle insertion part 23D is arranged in a concave line in the circumferential direction. Further, the pushing portion 22D is arranged so as to be freely inserted into the concave portion 12 (see FIG. 1) between the convex portions 11 and 11 in the axial direction of the support roll 10D. The idle insertion portion 23D is arranged so that the convex portion 11 (see FIG. 1) of the support roll 10D can be loosely inserted.

The non-woven fabric having a concave-convex shape produced by the non-woven fabric manufacturing apparatus and manufacturing method of the present invention can be applied to constituent members of various articles. Applicable articles include, for example, absorbent articles, cleaning supplies, filter materials and the like.
In the case of an absorbent article, it is preferable to apply it to a surface sheet from the viewpoint of making it soft to the touch. When arranged as a surface sheet, the contact area with the skin is reduced, the sticky feeling and the stuffy feeling of the skin are suppressed, and the dry feeling is excellent, which is preferable. The absorbent articles include, for example, diapers, sanitary napkins, urine absorbing pads, panty liners, and the like, which are attached to the body and have a function of absorbing body fluids.

1 Manufacturing equipment 10, 10D Support roll 10S Surface of support roll 11 Convex part 12 Concave part 20, 20A, 20B, 20D Pushing body 21,21A, 21B, 21D Unit 22, 22A, 22B, 22D Pushing part 23, 23A, 23B, 23D Free insertion part 25 Concave part 31 Rotating shaft 32 Convex part

Claims (14)

It is a method for manufacturing a non-woven fabric in which a fiber material is supplied between a support roll and a push-in body to form irregularities.
On the surface of the support roll, convex portions and concave portions are alternately arranged along the axial direction of the support roll.
In the push-in body, the idle insertion portion in which the convex portion is loosely inserted and the push-in portion loosely inserted in the concave portion are alternately arranged along the width direction of the push-in body parallel to the axial direction of the support roll. It has a unit and a moving mechanism that enables the unit to move in the width direction.
A method for producing a non-woven fabric, in which the position of the unit in the width direction is controlled by the moving mechanism to perform the loose insertion, and the unevenness shaping on the fiber material is carried out. The method for producing a non-woven fabric according to claim 1, wherein the push-in body has a plurality of the units, and each of the units is provided with the moving mechanism. The method for producing a non-woven fabric according to claim 1 or 2, which comprises a heating step in which the support roll is heated. The fiber material is a fiber web
The non-woven fabric according to claim 3, wherein the fibers of the fiber web are formed into irregularities by performing the loose insertion, and then the fibers of the fiber web along the concave-convex shape of the support roll are fused to each other by the heating step. Method. The fiber material is a non-woven fabric
The method for producing a non-woven fabric according to claim 3, wherein the fiber fusion force of the non-woven fabric arranged on the support roll is weakened by the heating step, and then the non-woven fabric is subjected to the loose insertion to form unevenness on the non-woven fabric. The method for producing a non-woven fabric according to any one of claims 3 to 5, wherein the heating step is a step of blowing hot air toward the support roll that supports the fiber material. The support roll attracts the fiber material toward the inside of the support roll.
The fibrous material is formed into irregularities by performing the free insertion.
Another fiber material is supplied onto the fiber material in a state where the fiber material is made to follow the uneven shape of the support roll by the suction.
The fibrous material and the other fibrous material are sandwiched between the support roll and the smoothing roll and conveyed in a laminated state, and the smoothing roll is heated to melt the fibrous material and the other fibrous material. The method for producing a non-woven fabric according to any one of claims 1 to 6, which is to be worn. The method for producing a non-woven fabric according to any one of claims 1 to 7, wherein a spline is used for the moving mechanism. A non-woven fabric manufacturing device that supplies a fiber material between the support roll and the push-in body to shape the unevenness.
On the surface of the support roll, convex portions and concave portions are alternately arranged along the axial direction of the support roll.
In the push-in body, the idle insertion portion in which the convex portion is loosely inserted and the push-in portion loosely inserted in the concave portion are alternately arranged along the width direction of the push-in body parallel to the axial direction of the support roll. It has a unit and a moving mechanism that enables the unit to move in the width direction.
A non-woven fabric manufacturing apparatus that controls the position of the unit in the width direction by the moving mechanism to perform the loose insertion and perform unevenness shaping on the fiber material. The non-woven fabric manufacturing apparatus according to claim 9, wherein the push-in body has a plurality of the units, and each of the units is provided with the moving mechanism. The non-woven fabric manufacturing apparatus according to claim 9 or 10, further comprising a heating apparatus for heating the support roll. The non-woven fabric manufacturing device according to claim 11, wherein the heating device blows hot air toward the support roll that supports the fiber material. The non-woven fabric manufacturing apparatus according to any one of claims 9 to 12, which has a smoothing roll in contact with the outer peripheral surface of the support roll on the downstream side of the push-in body, and the smoothing roll has a heating mechanism. The non-woven fabric manufacturing apparatus according to any one of claims 9 to 13, wherein the moving mechanism is a spline.

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