Method for manufacturing a stretchable sheet and apparatus for manufacturing a stretchable sheet

Abstract

To provide a method and an apparatus for producing a stretchable sheet, which can stably convey a thread-like elastic body wound between a pair of conveying belts and efficiently produce a stretchable sheet having a large width.SOLUTION: A method for producing a stretchable sheet includes: a winding step of continuously winding a thread-like elastic body 24 around a pair of conveying belts 50, 50 that are arranged with a space therebetween in an orthogonal direction Y1; a conveying step of conveying the wound thread-like elastic body 24 in a conveying direction X1; and an integrating step of holding the conveyed thread-like elastic body 24 between a pair of continuous sheets 23a, 23b and fixing the thread-like elastic body 24 between the pair of continuous sheets 23a, 23b. Each of the pair of conveying belts 50, 50 includes an upper belt 51 and a lower belt 55 which are arranged in a height direction Z. In the conveying step, the elongation rate of the wound thread-like elastic body 24 in the height direction Z is gradually increased toward a downstream side in the conveying direction X1.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a stretchable sheet and an apparatus for manufacturing a stretchable sheet.

Background Art

[0002] There is known a disposable diaper of a spread type, which includes a stretchable waist panel and a fastening tape is provided on the waist panel. The waist panel is formed of a stretchable sheet in which a plurality of filamentary elastic bodies are fixed in an extended state between a pair of sheets. From various viewpoints such as shape followability and stability during manufacturing, the manufacturing method of the stretchable sheet has been studied. For example, in Patent Document 1, after both ends or a portion other than one end of an elastic stretchable member extended in the width direction is adhered and fixed to a first sheet, the extended state is released and the non-adhered portion of the elastic stretchable member is contracted to a non-extended state, and a contraction step; and a second adhesion step of sandwiching and adhering and fixing the extended portion and the non-extended portion of the elastic stretchable member between a first sheet and a second sheet to obtain a laminate are included, and a manufacturing method of a tape-type disposable diaper is disclosed.

[0003] Also, the present applicant has previously disclosed a manufacturing method of a stretchable sheet including a supply step of introducing a filamentary elastic body in an extended state into an elastic body winding means at a speed equal to or higher than the winding speed with respect to a pair of conveyor belts, a conveying step of continuously winding and conveying the filamentary elastic body by the elastic body winding means around a filament conveying longitudinal structure, and an integration step of sandwiching and fixing the filamentary elastic body between a pair of sheets (Patent Document 2).

[0004] Patent Document 3 discloses a manufacturing method using a winding mechanism for winding a filamentary elastic body fed out at a predetermined tension in an extended state around a conveying mechanism, and introducing the filamentary elastic body into the winding mechanism at a second speed slower than a first speed of winding around the conveying mechanism.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Japanese Patent Publication No. 2010-022550 [Patent Document 2] Japanese Patent Publication No. 2012-090835 [Patent Document 3] Japanese Patent Publication No. 2014-128435 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] In the methods for manufacturing stretchable sheets described in Patent Documents 1 to 3, a filamentous elastic body is continuously wound around a pair of spaced-apart conveyor belts, the wound filamentous elastic body is fixed between the pair of continuous sheets, and both ends of the filamentous elastic body located between the pair of conveyor belts are cut to manufacture a stretchable sheet. In this stretchable sheet, the direction of extension of the filamentous elastic body coincides with the width direction of the sheet. To increase the width (length in the width direction) of this stretchable sheet, it is conceivable to increase the distance between the pair of conveyor belts. However, increasing the distance between the pair of conveyor belts tends to make the conveyance of the filamentous elastic body unstable, and there is a risk that the filamentous elastic body will be cut during conveyance. Patent Documents 1 to 3 do not disclose any technology to solve the above problems.

[0007] Therefore, the object of the present invention is to provide a method for manufacturing an elastic sheet and an apparatus for manufacturing an elastic sheet that can stably convey a filamentous elastic material wound between a pair of conveyor belts and efficiently produce an elastic sheet of a large width. [Means for solving the problem]

[0008] The present invention relates to a method for manufacturing an elastic sheet, comprising a fixing step of fixing an elongated filamentous elastic body between a pair of continuous sheets while conveying the pair of continuous sheets and a filamentous elastic body along the conveying direction. In one embodiment, the fixing step is: An adhesive application step of applying adhesive to one or both of the pair of continuous sheets in the transport state, A winding step of continuously winding the filamentous elastic body around a pair of conveyor belts spaced apart in a direction perpendicular to the conveying direction, A conveying step in which the wound filamentous elastic body is conveyed in the conveying direction by the pair of conveying belts, An integration step in which the filamentous elastic body in the transport state is sandwiched between the pair of continuous sheets and the filamentous elastic body is fixed between the pair of continuous sheets, It is preferable that the process includes a cutting step after the integration step, in which the thread-like elastic bodies extending from each of the two ends in the width direction of the continuous sheet are cut. In one embodiment, it is preferable that each of the pair of conveyor belts comprises an upper belt and a lower belt arranged in the height direction of the conveyor belt. In one embodiment, it is preferable that, in the conveying process, the elongation rate of the wound filamentous elastic body in the height direction is gradually increased toward the downstream direction of the conveying process.

[0009] The present invention also relates to an apparatus for manufacturing stretchable sheets, which fixes an elongated filamentous elastic body between a pair of continuous sheets while conveying the pair of continuous sheets along the conveying direction. In one embodiment, the manufacturing apparatus preferably comprises: an adhesive application means for applying adhesive to one or both of the pair of continuous sheets in a conveying state; a pair of conveyor belts spaced apart in an orthogonal direction perpendicular to the conveying direction; a winding means for continuously winding the filamentous elastic body around the pair of conveyor belts; an integrating means for fixing the wound filamentous elastic body between the pair of continuous sheets; and a cutting means for cutting the filamentous elastic body extending from each of the widthwise ends of the continuous sheets. In one embodiment, each of the pair of conveyor belts is preferably comprised of an upper belt and a lower belt arranged in the height direction of the conveyor belt, and the distance between the upper belt and the lower belt gradually increases toward the downstream direction in the conveying direction. [Effects of the Invention]

[0010] According to the method for manufacturing an elastic sheet and the apparatus for manufacturing an elastic sheet of the present invention, a filamentous elastic material wound between a pair of conveyor belts can be stably conveyed, and an elastic sheet of a large width can be efficiently manufactured. [Brief explanation of the drawing]

[0011] [Figure 1] Figure 1 is a plan view showing a deployable disposable diaper using a waist panel, obtained by the method for manufacturing the stretchable sheet of the present invention. [Figure 2] Figure 2 is a schematic diagram showing one embodiment of the manufacturing apparatus for the stretchable sheet of the present invention. [Figure 3] Figure 3 is a perspective view showing the winding means, conveying device, and integrating means shown in Figure 2. [Figure 4] Figure 4 is a cross-sectional view showing the conveyor belt shown in Figure 2 and the support member that supports the conveyor belt. [Figure 5] Figure 5 is a schematic side view of the conveyor belt shown in Figure 2. [Figure 6] Figure 6 is a schematic plan view showing the conveyor belt shown in Figure 2. [Figure 7] Figure 7 is a schematic perspective view showing the transport state of a filamentous elastic material wound around a conveyor belt. [Modes for carrying out the invention]

[0012] The present invention will be described below with reference to the drawings, based on its preferred embodiments. First, an embodiment of the method for manufacturing an elastic sheet and an elastic sheet manufactured by the apparatus for manufacturing the elastic sheet of the present invention will be described. The elastic sheet of this embodiment is used as a waist panel for a deployable disposable diaper. The disposable diaper 1 shown in Fig. 1 (hereinafter also simply referred to as "diaper 1") has, in the worn state, a ventral part A arranged on the ventral side of the wearer, a dorsal part B arranged on the dorsal side of the wearer, and a crotch part C located between the ventral part A and the dorsal part B. The crotch part C is a part arranged at the crotch of the wearer in the worn state of the diaper 1. The ventral part A is a part arranged on the ventral side, i.e., the front side of the wearer, rather than the crotch part C in the worn state of the diaper 1. The dorsal part B is a part arranged on the dorsal side, i.e., the rear side of the wearer, rather than the crotch part C in the worn state of the diaper 1. The ventral part A, the crotch part C, and the dorsal part B correspond to the respective regions when the diaper 1 is divided into three equal parts in the vertical direction X. As shown in Fig. 1, the diaper 1 has a vertical direction X corresponding to the front-back direction of the wearer and a horizontal direction Y orthogonal to this. In this specification, the "front-back direction of the wearer" refers to the direction extending from the ventral side of the wearer through the crotch to the dorsal side. The diaper 1 extends in the vertical direction X extending from the ventral part A through the crotch part C to the dorsal part B.

[0013] The diaper 1 has an absorbent main body 15, a pair of left and right waist panels 20, 20 continuously provided on both outer sides of the left and right of the dorsal part B, and a pair of left and right panel materials 19, 19 continuously provided on both outer sides of the left and right of the ventral part A (see Fig. 1). The absorbent main body 15 includes a liquid-permeable surface sheet 11, a liquid-impermeable or water-repellent back sheet 13, and an absorber 14 interposed between these two sheets 11, 13, and these are integrally formed by known joining means such as an adhesive. The absorber 14 becomes the main liquid-absorbing part for excreta such as urine.

[0014] The diaper 1 has a pair of leak - proof cuffs 16, 16 made of a liquid - resistant or water - repellent and breathable sheet material on both left and right sides along the longitudinal direction X on the skin - facing surface of the absorbent body 15. This leak - proof cuff 16 has a breathable sheet and a cuff elastic member 17 which is between the sheets and is fixed in an extended state in the longitudinal direction X at the inner end in the transverse direction Y. The inner end in the transverse direction Y of the leak - proof cuff 16 is a free end, and when the cuff elastic member 17 contracts, the free end stands up at least in the crotch part C, preventing the lateral outward flow of excreted liquids such as urine. The outer end in the transverse direction Y of the leak - proof cuff 16 is fixed on the surface sheet 11. The diaper 1 also has leg elastic members 18 for forming leg gathers at parts arranged around the legs on both left and right sides of the absorbent body 15. The leg elastic members 18 are arranged in an extended state in the longitudinal direction X, and leg gathers are formed by the contraction of the elastic members 18 in the worn state.

[0015] In the deployed and extended state of the diaper 1, the absorbent body 15 is rectangular in shape and long in the longitudinal direction X, and the panel material 19 is trapezoidal. The "deployed and extended state" of the diaper 1 means that the diaper 1 is in a deployed state and is expanded until each elastic member of the diaper 1 is extended to the design dimensions (the same as the dimensions when it is spread flat in a state where the influence of the elastic members is completely excluded).

[0016] Each of the pair of waist panels 20, 20 consists of an elastic sheet 21 that is stretchable in the lateral direction Y. The waist panel 20 is rectangular in its unfolded and extended state and has two sheets 23 and a plurality of thread-like elastic bodies 24 arranged between these sheets 23 in an extended state, which are integrated by means of adhesive or fusion. In this waist panel 20, the thread-like elastic bodies 24 are fixed in an extended state in the lateral direction Y and are intermittently arranged in the longitudinal direction X. In this embodiment, the inner end of the waist panel 20 in the lateral direction Y is fixed to both sides of the back side B of the absorbent body 15, and a fastening tape 26 is fixed to the outer end in the lateral direction Y. The fastening tape 26 has a fastening portion that can be detachably fastened to a fastening area (not shown) on the non-skin-facing surface of the ventral side A of the diaper 1. The fastening area is made of an appropriate material depending on the material of the fastening portion. For example, if the fastening portion is the male component of a mechanical fastener, the fastening area can be the female component of the mechanical fastener, which can engage with the male component. This can be a fibrous sheet, such as a knitted fabric or a nonwoven fabric.

[0017] In the diaper 1 of this embodiment, the elastic sheet 21 constituting the waist panel 20 is fixed such that the conveying direction X1 of the sheet during manufacturing is parallel to the vertical direction X, and the direction Y1 (orthogonal direction Y1) perpendicular to the conveying direction X1 of the elastic sheet 21 during manufacturing coincides with the horizontal direction Y.

[0018] The forming materials of diaper 1 will be described. The sheet 23 and panel material 19 constituting the waist panel 20 can be used without particular restrictions, as long as they are commonly used in absorbent articles such as disposable diapers. For example, the sheet 23 and panel material 19 can be nonwoven fabric, woven fabric, film, or laminated sheets thereof. The surface sheet 11 and back sheet 13 constituting the absorbent body 15 can be used without particular restrictions, as long as they are commonly used in absorbent articles such as disposable diapers. For example, the surface sheet 11 can be a hydrophilic and liquid-permeable nonwoven fabric, and the back sheet 13 can be a liquid-impermeable or water-repellent resin film or a laminate of resin film and nonwoven fabric. The absorbent body 14 can be an absorbent core made of pulp fibers or other fibers, or an absorbent core holding water-absorbent polymer particles thereon, covered with a core wrap sheet made of water-permeable thin paper or nonwoven fabric. The sheet constituting the leak-proof cuff 16 can be an elastic film, nonwoven fabric, woven fabric, or laminated sheets thereof.

[0019] The filamentous elastic body 24, the cuff elastic member 17, and the leg elastic member 18 can be made from filamentous stretchable materials such as natural rubber, polyurethane, polystyrene-polyisoprene copolymer, polystyrene-polybutadiene copolymer, or polyethylene-α-olefin copolymer such as ethyl acrylate-ethylene. The filamentous elastic body in this invention includes not only those with a circular or square cross-section, but also those with an elliptical or rectangular cross-section, or other narrow strip-like shapes, and multifilament types can also be used. The width (or diameter) of the filamentous elastic body 24 provided in the stretchable sheet 21 is, for example, 0.1 mm or more and 3 mm or less, preferably 1 mm or less. As the fastening tape 26, for example, one can be used in which a hook member of a mechanical fastener is attached to one side of a tape base material such as nonwoven fabric by heat fusion or adhesive.

[0020] As one embodiment of the stretchable sheet, the waist panel 20 of diaper 1 was given as an example, but the stretchable sheet is not limited to this.

[0021] Next, preferred embodiments of the method for manufacturing the stretchable sheet and the apparatus for manufacturing the stretchable sheet of the present invention will be described with reference to Figures 2 to 7. Figure 2 shows a schematic diagram of the manufacturing apparatus 100 of the stretchable sheet according to this embodiment (hereinafter also simply referred to as "manufacturing apparatus 100"). The manufacturing apparatus 100 of this embodiment is an apparatus that continuously manufactures stretchable sheets 21 by integrating continuous sheets 23a, 23b and filamentous elastic bodies 24.

[0022] The manufacturing apparatus 100 of this embodiment has a conveying direction X1 for conveying the filamentous elastic body 24 in one direction, an orthogonal direction Y1 perpendicular to the conveying direction X1, and a height direction Z perpendicular to both the conveying direction X1 and the orthogonal direction Y1. The orthogonal direction Y1 coincides with the width direction of the continuous sheets 23a and 23b, which will be described later. In the manufacturing apparatus 100 of this embodiment, the height direction Z coincides with the vertical direction, and the conveying direction X1 coincides with the horizontal direction. Furthermore, the surfaces of the continuous sheets 23a and 23b that are passed between the pair of nip rollers 61 and 62, which will be described later, are arranged to be parallel to the horizontal direction. The manufacturing apparatus 100 of this embodiment includes a conveying means 5 for conveying a filamentous elastic body 24 extended in the orthogonal direction Y1 along the conveying direction X1, a winding means 4 for continuously winding the filamentous elastic body 24 around the conveying means 5, an introduction means 3 for introducing the filamentous elastic body 24 into the winding means 4, adhesive application means 71a, 71b for applying adhesive to continuous sheets 23a, 23b, an integrating means 6 for fixing the filamentous elastic body 24 sandwiched between a pair of continuous sheets 23a, 23b, and a cutting means 8 for cutting the filamentous elastic body 24 extending from both ends in the width direction of the continuous sheets 23a, 23b (see Figure 2).

[0023] In this embodiment, the manufacturing apparatus 100 is arranged in the following order from upstream in the transport direction X1: introduction means 3, winding means 4, transport means 5, integration means 6, and cutting means 8. The cutting means 8 partially overlaps with the integration means 6 in the transport direction X1. The adhesive application means 71a is located upstream of the point where it merges with the transport path of the filamentous elastic body 24, in the transport path of the continuous sheets 23a and 23b.

[0024] The introduction means 3 is installed upstream of the winding means 4 in the transport direction X1 and supplies the filamentous elastic body 24 to the winding means 4. The introduction means 3 includes a tension adjustment means 30 and a speed adjustment means 35. The tension adjustment means 30 adjusts the tension of the filamentous elastic body 24 to a constant level before it is introduced into the winding means 4. The tension adjustment means 30 includes a tensioner (not shown) that applies tension to the filamentous elastic body 24 being unwound from the winding body (not shown) of the filamentous elastic body 24 by means of a brake, an unwinding roller 31 located downstream of the tensioner that unwinds the filamentous elastic body 24, and a tension sensor 32 located downstream of the unwinding roller 31 that measures the tension of the filamentous elastic body 24 being unwinded from the roller 31 (see Figure 2). The unwinding roller 31 has its rotation axis axially aligned with the orthogonal direction Y1, and a motor (not shown) is attached to the drive unit of the roller 31. The unwinding roller 31 is used with the filamentous elastic body 24 wound around its outer circumference. Based on the detection output from the tension sensor 32, the tension adjustment means 30 controls the rotation speed of the unwinding roller 31 (motor) by a control unit (not shown) provided in the manufacturing apparatus 100. This allows the feed roller 31 to unwind the filamentous elastic material 24 from its winding body at a predetermined tension. A known yarn feeding device capable of supplying the filamentous elastic material 24 at a predetermined tension can be used as the tension sensor 32.

[0025] The speed adjustment means 35 is located downstream of the tension adjustment means 30 and adjusts the supply speed at which the filamentous elastic body 24 is supplied to the winding means 4. The speed adjustment means 35 in this embodiment includes a feed roller 37 and guide rollers 36a and 36b located upstream and downstream of the feed roller 37. The feed roller 37 is positioned between the winding means 4 (described later) and the unwinding roller 31, and the axial direction of the rotation axis of the feed roller 37 is aligned with the orthogonal direction Y1. A servo motor (not shown) is attached to the drive unit of the feed roller 37 and it is controlled by a control unit (not shown) provided in the manufacturing apparatus 100. In this embodiment, the manufacturing apparatus 100 continuously feeds out the filamentous elastic body 24 using an introduction means 3 equipped with tension adjustment means 30 and speed adjustment means 35, and introduces the filamentous elastic body 24 in an extended state into the winding means 4.

[0026] The winding means 4 includes a rotating arm 40 that continuously winds the filamentous elastic body 24 onto a pair of conveyor belts 50, 50 (described later), and a drive unit 47 that rotates the rotating arm 40 (see Figure 3). The rotating arm 40 is a rod-shaped member, with one end 42 of a vertical portion 41 extending in the vertical direction bent at approximately a right angle downstream of the conveying direction X1, and the other end 43 of the vertical portion bent at approximately a right angle upstream of the conveying direction X1, forming a crank shape, with both the one end 42 and the other end 43 extending in the conveying direction X1. Hereinafter, the one end 42 of the rotating arm 40 will also be called the "circumferential portion 42," and the other end 43 of the rotating arm 40 will also be called the "shaft portion 43." The vertical portion 41 of the rotating arm 40 is at an angle to the circumferential portion 42 and the shaft portion 43, respectively, while the circumferential portion 42 and the shaft portion 43 are approximately parallel. The shaft portion 43 has an inlet for the filamentous elastic body 24 at one end on the upstream side in the conveying direction X1, and the circumferential portion 42 has an outlet 42a for the filamentous elastic body 24 at its tip (one end on the downstream side in the conveying direction X1). The rotating arm 40 passes the filamentous elastic body 24 introduced from the inlet through the shaft portion 43, the vertical portion 41, and the circumferential portion 42 in that order, and leads out the filamentous elastic body 24 from the outlet 42a. Various known members (such as driven rolls or low-friction members) that can reduce friction between the filamentous elastic body 24 and the rotating arm 40 may be arranged at the bends between the vertical portion 41 and the circumferential portion 42 or between the vertical portion 41 and the shaft portion 43, or at the outlet 42a.

[0027] The outlet 42a of the circumferential section 42 is positioned downstream of the upstream end of the conveyor belts 50, 50, which will be described later. In other words, the leading edge of the circumferential section 42 overlaps with the conveyor belts 50, 50 in the conveying direction X1. The drive unit 47 of the winding means 4 rotates the shaft portion 43 of the rotating arm 40. The drive unit 47 comprises a servo motor 48 and an interlocking belt 49 that links the shaft portion 43 to the rotation of the servo motor 48. The interlocking belt 49 is stretched between the outer circumference of the servo motor 48 and the outer circumference of the shaft portion 43, so that when the servo motor 48 rotates, the shaft portion 43 rotates in the same direction in conjunction with the interlocking belt 49. This rotation of the shaft portion 43 causes the circumferential portion 42 to circumfer the outer circumference of the conveyor belt 50. As a result, the filamentous elastic body 24 discharged from the outlet 42a is wound between the pair of conveyor belts 50, 50. In this manner, the rotating arm 40 continuously winds the captured filamentous elastic body 24 around the upstream end of the pair of conveyor belts 50, 50. The rotational speed of the rotating arm 40, i.e., the rotational speed of the servo motor 48, is controlled by a control unit (not shown) provided in the manufacturing apparatus 100.

[0028] The conveying means 5 comprises a pair of conveying belts 50, 50 spaced apart in the orthogonal direction Y1, and conveys the wound filamentous elastic body 24 in the conveying direction X1 by the pair of conveying belts 50, 50 and introduces it between a pair of continuous sheets 23a, 23b, which will be described later. The pair of conveying belts 50, 50 are symmetrical with respect to the central position between them and have the same configuration. Each of the pair of conveyor belts 50, 50 has two upper and lower belts, an upper belt 51 and a lower belt 55, as shown in Figures 2 to 5. That is, the conveyor belt 50 has an upper belt 51 and a lower belt 55 arranged in the height direction Z. The upper belt 51 and the lower belt 55 are each endless rotating belts. The upper belt 51 and the lower belt 55 are positioned opposite each other in the height direction Z, with the upper belt 51 above and the lower belt 55 below (see Figure 3).

[0029] As shown in Figure 3, the upper belt 51 is stretched between a pair of pulleys 52 and 53 that are spaced apart in the conveying direction X1. The pair of pulleys 52 and 53 are located at both ends of the conveying belt 50 in the conveying direction X1. The rotation axes of these pulleys 52 and 53 are parallel to each other, and the rotation axes are inclined with respect to the orthogonal direction Y1. As a result, each surface of the upper belt 51 and the lower belt 55 is inclined with respect to the horizontal direction. These surfaces of the belts 51 and 55 are the forward-moving sections 51a and 55a and the reverse-moving sections 51b and 55b, respectively, which will be described later.

[0030] The upper belt 51 has a forward-moving portion 51a that contacts the filamentous elastic body 24 wound by the winding means 4 and conveys the filamentous elastic body 24 along the conveying direction X1, and a reverse-moving portion 51b that travels in the opposite direction to the forward-moving portion 51a (see Figure 3). The forward-moving portion 51a of the upper belt 51 is the portion that travels from the upstream pulley 52 to the downstream pulley 53 of the upper belt 51. The reverse-moving portion 51b is the portion that travels from the downstream pulley 53 to the upstream pulley 52 of the upper belt 51. In the upper belt 51, the forward-moving portion 51a and the reverse-moving portion 51b are arranged opposite each other in the height direction Z, with the forward-moving portion 51a located above and the reverse-moving portion 51b located below (see Figure 3). The upper belt 51 rotates as the inner surfaces of the forward-moving portion 51a and the reverse-moving portion 51b at both ends in the conveying direction X1 come into contact with the rotating pulleys 52 and 53.

[0031] The lower belt 55 has the same configuration as the upper belt 51. As shown in Figure 3, the lower belt 55 is stretched between a pair of pulleys 56 and 57 provided at both ends of the conveying direction X1 in the conveying belt 50. The lower belt 55 also has a forward-running portion 55a that contacts the filamentous elastic body 24 wound by the winding means 4 and conveys the filamentous elastic body 24 along the conveying direction X1, and a reverse-running portion 55b that runs in the opposite direction to the forward-running portion 55a (see Figure 3). The forward-running portion 55a of the lower belt 55 is the portion that runs from the upstream pulley 56 to the downstream pulley 57 in the lower belt 55. The reverse-running portion 55b is the portion that runs from the downstream pulley 57 to the upstream pulley 56 in the lower belt 55. In the lower belt 55, the forward-moving portion 55a and the reverse-moving portion 55b are positioned opposite each other in the height direction Z, with the forward-moving portion 55a located below and the reverse-moving portion 55b located above (see Figure 3). The lower belt 55 rotates as the inner surfaces of the forward-moving portion 55a and the reverse-moving portion 55b come into contact with the rotating pulleys 56 and 57 at both ends in the conveying direction X1. In this embodiment, the conveyor belt 50 has the reverse-running portions 51b and 55b of the upper belt 51 and lower belt 55 facing each other in the height direction Z.

[0032] In a cross-sectional view along the orthogonal direction Y1 of the pair of conveyor belts 50, 50, the upper belts 51, 51 and the lower belts 55, 55 are arranged symmetrically with respect to the orthogonal center line CY (see Figure 4). More specifically, the forward-moving portions 51a and reverse-moving portions 51b of the upper belts 51, 51 are arranged to be inclined symmetrically with respect to the orthogonal center line CY. Similarly, the forward-moving portions 55a and reverse-moving portions 55b of the lower belts 55, 55 are arranged symmetrically with respect to the orthogonal center line CY and are inclined with respect to the orthogonal center line CY. The "orthogonal center line CY" is a virtual straight line that bisects the total width (total length in the orthogonal direction Y1) of the pair of conveyor belts 50, 50 and extends in the height direction Z. The upper belt 51 and the lower belt 55 are inclined with respect to the horizontal direction such that the outer ends of the forward-moving portions 51a and 55a are located further outward in the orthogonal direction Y1 than the outer ends of the reverse-moving portions 51b and 55b. As a result, the filamentous elastic body 24 conveyed by the conveyor belt 50 is conveyed while being stretched between the forward-moving portion 51a of the upper belt 51 and the forward-moving portion 55a of the lower belt 55 at both ends in the orthogonal direction Y1. In this embodiment, the conveyor belts 50, 50 are supported by belt support guides 59, which will be described later, so that the upper belt 51 and the lower belt 55 are inclined with respect to the horizontal direction (orthogonal direction Y1).

[0033] The filamentous elastic material 24 wound around the conveyor belt 50 is conveyed by the movement of the forward-moving portions 51a and 55a of the upper belt 51 and the lower belt 55, respectively. The feed speed (movement speed) of these forward-moving portions 51a and 55a is the conveying speed. Each of the pulleys 52, 53, 56, and 57 on the conveyor belt 50 is connected to a servo motor (not shown) in its drive unit, allowing the rotational speed of the upper belt 51 and the lower belt 55 to be changed. It is preferable that both the upper belt 51 and the lower belt 55 are timing belts. The rotational speeds of these belts 51 and 55, that is, the rotational speeds of the servo motors (not shown) arranged in the drive units of the pulleys 52, 53, 56, and 57, are controlled by a control unit (not shown) provided in the manufacturing apparatus 100. From the viewpoint of conveying the filamentous elastic material 24 between the pair of conveyor belts 50, 50 in a more parallel manner, it is preferable that each of the pair of conveyor belts 50 is controllable so that the conveying speeds of the upper belt 51 and the lower belt 55 are different from each other.

[0034] Each of the pair of conveyor belts 50, 50 in this embodiment is equipped with a belt support guide 59 that maintains the forward-moving portion 51a, 55a and the reverse-moving portion 51b, 55b in an inclined state with respect to the horizontal direction between a pair of pulleys in the conveying direction X1 (see Figure 4). The belt support guide 59 is a plate-like body of a predetermined width that extends in the conveying direction X1 and is positioned from upstream of the winding start point of the filamentous elastic body 24 to downstream of the integrating means 6 (a pair of nip rollers 61, 62) in the conveying direction X1. Note that the belt support guide 59 is not shown in Figures 2 and 3.

[0035] The belt support guide 59 has a guide body 59a located inward in the direction Y1 of the conveyor belt 50 when viewed in cross-section along the direction Y1 of the conveyor belt 50, and three guide pieces 59b and 59c projecting outward from the guide body 59a in the direction Y1 of the conveyor belt 50. Of these three guide pieces, the central guide piece 59b, located in the center in the height direction Z, is positioned between the reverse-running portion 51b of the upper belt 51 and the reverse-running portion 55b of the lower belt 55. The guide pieces 59c and 59c located on either side of the central guide piece 59b in the height direction Z are positioned between the forward-running portion 51a and the reverse-running portion 51b of the upper belt 51, and between the forward-running portion 55a and the reverse-running portion 55b of the lower belt 55. These guide pieces 59b and 59c protrude from the guide body 59a in an inclined state with respect to the horizontal, thereby supporting the forward-moving portions 51a and 55a and the reverse-moving portions 51b and 55b of the upper belt 51 and lower belt 55 in this inclined state. As described above, the belt support guide 59 supports the upper belt 51 and lower belt 55, so that the outer ends of the forward-moving portions 51a and 55a in the orthogonal direction Y1 are located further outward in the orthogonal direction Y1 than the outer ends of the reverse-moving portions 51b and 55b in the orthogonal direction Y1. This prevents the reverse-moving portions 51b and 55b from contacting the filamentous elastic body 24, and allows the filamentous elastic body 24 to be smoothly transported while preventing interference by the reverse-moving portions 51b and 55b that travel in the opposite direction to the transport direction X1. Furthermore, the belt support guides 59, 59 can prevent contact between the forward-moving portion and the reverse-moving portion of the upper and lower belts 51, 55 by the guide pieces 59c, 59c positioned between the forward-moving portion and the reverse-moving portion.

[0036] The filamentous elastic body 24 wound around the conveyor belt 50 can exert a downward force on the forward-moving portions 51a, 51a of the upper belts 51, 51, and an upward force on the forward-moving portions 55a, 55a of the lower belts 55, 55. Even when such forces are applied, the belt support guides 59, 59 maintain the inclination and running position of each belt 51, 55 more stably. This makes it possible to more effectively prevent disturbances in the winding position of the filamentous elastic body 24 on the conveyor belt 50, such as fluctuations in the distance between the forward-moving portions 51a, 51a of the upper belts 51, 51 and the forward-moving portions 55a, 55a of the lower belt 55. Such "winding positions" are the winding points of the filamentous elastic body 24 on a pair of conveyor belts 50, 50, and are points that move from the upstream side to the downstream side in the conveying direction X1 as the conveyor belts 50 (forward-moving portions 51a, 55a) are conveyed.

[0037] In this embodiment, the pair of conveyor belts 50, 50 are supported by belt support guides 59, so that the upper belt 51 and the lower belt 55 are arranged symmetrically with respect to the height centerline CZ. The "height centerline CZ" is a virtual straight line that bisects the total height (total length in the height direction Z) of the pair of conveyor belts 50, 50 and extends in the orthogonal direction Y1. The upper belt 51 and lower belt 55 have their forward-moving portions 51a and 55a positioned approximately at the outer ends of their respective orthogonal Y1 directions (see Figure 4). Furthermore, the upper belt 51 and lower belt 55 have their reverse-moving portions 51b and 55b positioned approximately at the outer ends of their respective orthogonal Y1 directions (see Figure 4).

[0038] In each of the pair of conveyor belts 50, 50 of this embodiment, the distance t between the upper belt 51 and the lower belt 55 gradually increases toward the downstream direction of conveying X1 (see Figures 5 and 7). The distance t between the upper belt 51 and the lower belt 55 is the distance between the forward-moving portion 51a of the upper belt 51 and the forward-moving portion 55a of the lower belt 55 in the height direction Z. By gradually increasing this distance t toward the downstream direction of conveying X1, the elongation rate of the filamentous elastic material 24 wound around the pair of conveyor belts 50, 50 in the height direction Z can be gradually increased toward the downstream direction of conveying X1. In this embodiment, the upper belt 51 and lower belt 55 gradually expand by the same distance t toward the downstream direction of the conveying direction X1.

[0039] In this embodiment, the distance d between the pair of conveyor belts 50, 50 in a plan view also gradually increases toward the downstream direction of the conveying (see Figures 6 and 7). The distance d between the pair of conveyor belts 50, 50 is the distance between the forward-moving portions 51a, 51a of the pair of upper belts in the orthogonal direction Y1, or the distance between the forward-moving portions 55a, 55a of the pair of lower belts in the orthogonal direction Y1. As the distance d between the pair of conveyor belts 50, 50 gradually increases toward the downstream direction of the conveying direction X1, the elongation rate of the filamentous elastic body 24 wound between the pair of conveyor belts 50, 50 in the orthogonal direction Y1 can be gradually increased toward the downstream direction of the conveying direction X1. In this embodiment, the distance d between the forward-moving portions 51a, 51a of the pair of upper belts, and the distance d between the forward-moving portions 55a, 55a of the pair of lower belts, gradually increase by the same distance toward the downstream direction of the conveying direction X1.

[0040] The adhesive application means 71a and 71b apply adhesive to one or both of the pair of continuous sheets 23a and 23b before they join the transport path of the filamentous elastic body 24. In this embodiment, the adhesive application means 71a and 71b apply adhesive to each of the opposing surfaces of the pair of continuous sheets 23a and 23b in an arbitrary application pattern. The application method of the adhesive may be a pattern coating such as a stripe, spiral, or sine wave shape, or it may be a coating applied by spraying or solid coating over the entire surface. Known application devices such as coaters and sprayers can be used as the adhesive application means 71a and 71b. The pair of continuous sheets 23a and 23b, to which adhesive has been applied, are transported to the integrating means 6 and merge with the transport path of the filamentous elastic body 24.

[0041] The integration means 6 introduces the wound filamentous elastic body 24 between a pair of continuous sheets 23a and 23b to which adhesive has been applied, and integrates the continuous sheets 23a and 23b with the filamentous elastic body 24 (see Figure 2). The integrating means 6 of this embodiment is installed downstream of the upstream pulleys 52 and 56 on the conveyor belt 50 in the conveyor direction X1, and upstream of the downstream pulleys 53 and 57 in the conveyor direction X1. The integrating means 6 is also installed between a pair of conveyor belts 50, 50 in the orthogonal direction Y1. The integrating means 6 of this embodiment comprises a pair of nip rollers 61 and 62 located between the pair of conveyor belts 50, 50 in the orthogonal direction Y1 (see Figure 3).

[0042] The pair of nip rollers 61 and 62 can be cylindrical rollers made of metal or cylindrical rollers made of low-hardness silicone rubber. A servo motor (not shown) is attached to the drive unit of one of the pair of nip rollers 61 and 62, and the rotational speed is controlled by a control unit (not shown) provided in the manufacturing apparatus 100. In addition, a drive transmission gear is attached to the rotational shaft of each of the pair of nip rollers 61 and 62. This drive means (not shown) allows the rotational speed of the servo motor, i.e., the rotational speed of one of the nip rollers 61, to be controlled based on the production speed of the stretchable sheet. At that time, the drive transmission gear meshes, transmitting driving force to the other nip roller 62, and allowing the pair of nip rollers 61 and 62 to rotate. From the viewpoint of securely fixing the stretched filamentous elastic body 24 between the pair of continuous sheets 23a and 23b, in this embodiment, the bearing portions of the pair of nip rollers 61 and 62 are pressurized using a force such as hydraulic pressure, pneumatic pressure, or a spring.

[0043] In the integrating means 6 of this embodiment, the filamentous elastic body 24 being transported by the conveyor belt 50 is introduced between a pair of nip rollers 61 and 62 in an extended state in the orthogonal direction Y1. Then, with the filamentous elastic body 24 sandwiched between a pair of continuous sheets 23a and 23b, the filamentous elastic body 24 is fixed between the continuous sheets 23a and 23b by applying pressure with the nip rollers 61 and 62. In this way, the filamentous elastic body 24 is fixed between the continuous sheets 23a and 23b.

[0044] The cutting means 8 is equipped with a cutter whose contact point with the filamentous elastic body 24 during transport is a sharp cutting blade. The cutting means 8 is positioned between the transport belt 50 and a pair of nip rollers 61, 62 in the orthogonal direction Y1 (see Figure 2). This allows the filamentous elastic body 24 extending from both ends of the continuous sheets 23a, 23b in the width direction (orthogonal direction Y1) to be cut by the cutter while being transported. The cut filamentous elastic body 24 contracts in the orthogonal direction Y1 and fits within the width of the continuous sheets 23a, 23b. The cutting means 8 (cutter) is located between the upper belt 51 and the lower belt 55 in the height direction Z of each of the pair of conveyor belts 50, 50. Various known cutting means capable of cutting the filamentous elastic body 24 can be used for the cutting means 8 without particular limitations. For example, a roller cutter equipped with a cutter roller having a cutting blade extending circumferentially on its outer surface and an anvil roller that receives the cutting blade can be used. Alternatively, cutting may be performed by laser, heat, or the like. This cutting means 8 cuts both ends of the filamentous elastic material 24 extending from the continuous sheets 23a and 23b, thereby obtaining a continuous stretchable sheet 21 (hereinafter also referred to as the "continuous stretchable sheet 22"). Note that the cutting means 8 is not shown in Figure 3.

[0045] The manufacturing method for the stretchable sheet of this embodiment (hereinafter also simply referred to as the "manufacturing method") is carried out using the manufacturing apparatus 100 of the embodiment described above. The manufacturing method of this embodiment includes a fixing step of fixing the stretched filamentous elastic body 24 between the pair of continuous sheets 23a and 23b while conveying the pair of continuous sheets 23a and 23b along the conveying direction X1. The fixing process comprises an adhesive application process, an introduction process, a winding process, a conveying process, an integration process, and a cutting process. In this embodiment, the fixing process is carried out in the order of introduction, winding, conveying, and integration, with the adhesive application process performed in parallel with these processes. In the introduction, winding, conveying, and integration processes, the filamentous elastic body 24 is conveyed along the conveying direction X1. A pair of continuous sheets 23a and 23b, which have been conveyed along a conveying path separate from the conveying path of the filamentous elastic body 24, merge with the filamentous elastic body 24 in the integration process.

[0046] The adhesive application step involves applying adhesive to one or both of the pair of continuous sheets 23a and 23b in a transported state. In this embodiment, the adhesive application step is performed by the adhesive application means 71a and 71b described above, and adhesive is applied to both of the pair of continuous sheets 23a and 23b. After the adhesive application step, the pair of continuous sheets 23a and 23b are subjected to the integration step.

[0047] The introduction step is the step of introducing the filamentous elastic body 24 into the winding means 4, and is performed before the winding step. The introduction step in this embodiment includes a tension adjustment step for adjusting the tension of the filamentous elastic body 24 to a constant level, and a speed adjustment step for adjusting the supply speed of the filamentous elastic body 24. With this configuration, the tension of the filamentous elastic body 24 can be stabilized, and the filamentous elastic body 24 can be stably introduced into the winding means 4. From the viewpoint of further stabilizing the tension of the filamentous elastic body 24, it is preferable to perform the speed adjustment step after the tension adjustment step. Furthermore, from the same viewpoint as above, it is preferable to perform the speed adjustment process immediately before the winding process.

[0048] The tension adjustment process is performed by the tension adjustment means 30 described above. From the viewpoint of further stabilizing the tension of the filamentous elastic body 24, the elongation rate of the filamentous elastic body 24 adjusted in the tension adjustment process is preferably 1.5 times or more and 4.0 times or less, and more preferably 1.5 times or more and 2.5 times or less. The growth rate can be calculated using the following formula. Elongation rate=La / Lb La: Length of the elongated filamentous elastic body Lb: Length of the filamentous elastic material in its non-stretched state (natural length of the filamentous elastic material)

[0049] The speed adjustment process is performed by the speed adjustment means 35 described above. By including a speed adjustment process in the introduction process, the decrease in the amount of filamentous elastic material 24 supplied due to the transport resistance after the tension adjustment process can be further suppressed. From the viewpoint of more reliably achieving this effect, the speed adjustment process adjusts the supply speed of the filamentous elastic material 24 introduced into the winding means 4 to preferably 50 m / min or more and 1700 m / min or less, more preferably 300 m / min or more and 1000 m / min or less. This supply speed is adjusted by the rotation speed of the feed roller 37. In this embodiment, the filamentous elastic material 24 is passed between the feed roller 37 and the guide rollers 36a, 36b, and the supply speed of the filamentous elastic material 24 to the winding means 4 is adjusted by increasing or decreasing the rotation speed of the feed roller 37.

[0050] The winding process involves continuously winding the filamentous elastic body 24 around a pair of conveyor belts 50, 50 spaced apart in the orthogonal direction Y1. The winding process is performed by the winding means 4 described above. Specifically, the rotating arm 40 is rotated around the shaft portion 43 so that the circumferential portion 42 circles around the outer circumference of the upstream ends of the pair of conveyor belts 50 (see Figure 3). As a result, the filamentous elastic body 24 discharged from the outlet 42a of the circumferential portion 42 is wound around the upstream ends of the pair of conveyor belts 50, 50. This winding stretches the filamentous elastic body 24 between the pair of conveyor belts 50, 50. In this embodiment, the filamentous elastic body 24 is stretched between the pair of upper belts 51 in the orthogonal direction Y1, between the upper belt 51 and the lower belt 55 in one height direction Z, between the pair of lower belts 55 in the orthogonal direction Y1, and between the upper belt 51 and the lower belt 55 in the other height direction Z. In this case, in a cross-sectional view along the orthogonal direction Y1 of the pair of conveyor belts 50, 50, the filamentous elastic body 24 is stretched along the four sides of a roughly rectangular shape formed by the forward-moving portions 51a, 55a of the pair of upper belts 51, 51 and lower belts 55, 55 as corners (see Figure 4).

[0051] From the viewpoint of further suppressing the cutting of the filamentous elastic body 24, which will be described later, it is preferable to carry out the winding process under the following conditions. The elongation rate of the filamentous elastic body 24 when it is wound onto a pair of conveyor belts 50, 50 in the winding process is preferably the elongation rate adjusted by the tension adjustment process described above. That is, it is preferably 1.5 times or more and 4.0 times or less, and more preferably 1.5 times or more and 2.5 times or less. The elongation rate is determined by the method described above. The rotational speed of the rotating arm 40 during the winding process is preferably 250 rpm to 8000 rpm, and more preferably 1500 rpm to 5000 rpm.

[0052] The conveying process uses the pair of conveying belts 50, 50 described above to convey the filamentous elastic body 24 wound in the winding process in the conveying direction X1 and feed it to the integration process. In this embodiment, as described above, the conveying means 5 has a distance t between the upper belt 51 and the lower belt 55 in the height direction Z that gradually increases toward the downstream direction of the conveying direction X1 (see Figure 5). As a result, in the conveying process of this embodiment, the elongation rate of the wound filamentous elastic body 24 in the height direction Z is gradually increased toward the downstream direction of the conveying direction X1. This configuration has the following advantages in manufacturing the stretchable sheet 21.

[0053] The filamentous elastic material 24 is prone to vibration due to its elasticity. When vibration occurs in the filamentous elastic material 24 that is wound and conveyed between a pair of conveyor belts 50, 50, the filamentous elastic material 24 is more likely to come into contact with each other, or the filamentous elastic material 2 is more likely to come into contact with various components of the manufacturing apparatus 100, such as the belt support guide 59. This contact can cause the filamentous elastic material 24 to break unintentionally. In particular, when the distance d between the pair of conveyor belts 50, 50 (see Figures 6 and 7) is increased in order to manufacture a wide stretchable sheet 21, the length of the filamentous elastic material 24 between the pair of conveyor belts 50, 50 increases, making vibration and the resulting breakage of the filamentous elastic material 24 more likely. In the conveying process of this embodiment, the elongation rate of the filamentous elastic body 24 in the height direction Z is gradually increased downstream. As the conveying process moves downstream, the distance in the height direction Z between the filamentous elastic body 24a (hereinafter also referred to as "upper filamentous elastic body 24a"; see Figure 4) stretched between the upper belts 51, 51 in the orthogonal direction Y1 and the filamentous elastic body 24b (hereinafter also referred to as "lower filamentous elastic body 24b"; see Figure 4) stretched between the lower belts 55, 55 in the orthogonal direction Y1 increases. As a result, even if the upper filamentous elastic body 24a and the lower filamentous elastic body 24b vibrate, contact between these filamentous elastic bodies 24a and 24b can be effectively suppressed, thereby preventing unintended cutting of the filamentous elastic body 24 due to such contact. In this way, the conveying process of this embodiment enables stable conveying of the filamentous elastic body 24 wound between a pair of conveyor belts 50, 50. Such effects are effective in the efficient manufacture of stretchable sheets 21 with a large width (long length in the orthogonal direction Y1). Furthermore, by configuring the conveyor belt 50 so that the elongation rate of the filamentous elastic body 24 in the height direction Z gradually increases downstream, the rotating arm 40 of the winding means 4 can be made more compact.

[0054] From the viewpoint of more reliably achieving the above effects, it is preferable that the upper belt 51 and the lower belt 55 are arranged so as to be spaced apart from each other in the height direction Z toward the downstream direction of the conveying direction X1 (see Figure 5). From the same viewpoint as above, the angle θ2 between the upper belt 51 and the lower belt 55 in a side view of the pair of conveying belts 50, 50 (see Figure 5) is preferably 1° or more and 20° or less, more preferably 1° or more and 10° or less. Such an angle θ2 is the angle between the forward-moving portion 51a of the upper belt 51 and the forward-moving portion 55a of the lower belt 55 when the conveying belt 50 is viewed from the side, and is the angle between virtual straight lines that extend these forward-moving portions 51a and 55a toward the upstream direction of the conveying direction X1 (see Figure 5).

[0055] In this embodiment, the conveyor belt 50 has a distance t between the upper belt 51 and the lower belt 55 in the height direction Z that differs in the conveying direction X1, being minimum at the upstream end in the conveying direction X1 and maximum at the downstream end in the conveying direction X1. From the viewpoint of further suppressing vibration of the filamentous elastic body 24, the distance t1 (see Figure 5) between the upper belt 51 and the lower belt 55 at the winding start point P1 in the conveying direction X1 is preferably 10 mm or more and 25 mm or less, more preferably 10 mm or more and 20 mm or less. From the same viewpoint as above, the distance t2 (see Figure 5) between the upper belt 51 and the lower belt 55 at position P2 (see Figure 5) of the integrating means 6 in the conveying direction X1 is preferably 20 mm or more and 50 mm or less, more preferably 20 mm or more and 40 mm or less. Position P2 of the integrating means 6 in the conveying direction X1 is the position of the rotation axis of the pair of nip rollers 61 and 62 in the conveying direction X1 (see Figure 5). The distance t between the upper belt 51 and the lower belt 55 is the distance between the forward-moving portion 51a of the upper belt 51 and the forward-moving portion 55a of the lower belt 55 in the height direction Z. In this embodiment, the distance between the central axes of the pair of nip rollers 61 and 62 in the height direction Z is longer than the distance t2 between the upper belt 51 and the lower belt 55 at position P2 (see Figure 5) of the integrating means 6.

[0056] In the conveying process, it is preferable to gradually increase both the elongation rate in the height direction Z and the elongation rate in the orthogonal direction Y1 of the filamentous elastic body 24 (hereinafter also referred to as "the filamentous elastic body 24 in the wound state") wound between a pair of conveyor belts 50, 50, as we move downstream in the conveying direction X1. With this configuration, the entire filamentous elastic body 24 wound around the pair of conveyor belts 50, 50 can be stretched, and the difference in elongation rates in the height direction Z and the orthogonal direction Y1 can be reduced. As a result, the winding position of the filamentous elastic body 24 on the pair of conveyor belts 50, 50 can be maintained with higher precision, and the conveying of the filamentous elastic body 24 can be stabilized.

[0057] In this embodiment, the conveying means 5 gradually increases the distance t between the upper belt 51 and the lower belt 55 in the height direction Z, as well as the distance d between the pair of conveying belts 50, 50, toward the downstream direction of the conveying (see Figures 6 and 7). As a result, the elongation rates of the wound filamentous elastic body 24 in both the height direction Z and the orthogonal direction Y1 are gradually increased toward the downstream direction of the conveying direction X1. Furthermore, since the length of the wound filamentous elastic body 24 in the orthogonal direction Y1 is minimum at the winding start point P1 and increases toward the downstream direction of the conveying direction X1, a wide stretchable sheet 21 can be efficiently manufactured. This allows for a more compact design of equipment such as the winding means 4. Furthermore, since the lengths in the height direction Z and the orthogonal direction Y1 are minimized at the winding start point P1, vibrations of the filamentous elastic body 24 at point P1 can be effectively suppressed. These effects are particularly effective for the stable manufacture of stretchable sheets 21 with a large width (long length in the orthogonal direction Y1).

[0058] From the viewpoint of further suppressing vibration of the filamentous elastic body 24, it is preferable that the pair of conveyor belts 50, 50 are arranged to be spaced apart from each other in the orthogonal direction Y1 toward the downstream direction of conveying X1 (see Figure 6). From the same viewpoint as above, the angle θ1 between the pair of conveyor belts 50, 50 in a plan view (see Figure 6) is preferably 1° or more and 50° or less, more preferably 1° or more and 20° or less. Such an angle θ1 is the angle between the forward-moving portions 51a of the upper belt 51 when the pair of conveyor belts 50, 50 are viewed in a plan view, and is the angle between virtual straight lines that extend these forward-moving portions 51a, 51a toward the upstream direction of conveying X1 (see Figure 6).

[0059] In this embodiment, the distance d between a pair of conveyor belts 50, 50 in the orthogonal direction Y1 differs in the conveying direction X1, being minimum at the upstream end in the conveying direction X1 and maximum at the downstream end in the conveying direction X1. From the viewpoint of further suppressing vibration of the filamentous elastic body 24, the distance d1 (see Figure 6) between the pair of conveyor belts 50, 50 at the winding start point P1 in the conveying direction X1 is preferably 70 mm or more and 120 mm or less, more preferably 90 mm or more and 110 mm or less. From the same viewpoint as described above, the distance d2 (see Figure 6) between the pair of conveyor belts 50, 50 at position P2 (see Figure 5) of the integrating means 6 in the conveying direction X1 is preferably 160 mm or more and 230 mm or less, more preferably 200 mm or more and 220 mm or less. The distance d between a pair of conveyor belts 50, 50 in the orthogonal direction Y1 is the distance between the forward-moving portions 51a, 51a of the upper belt 51 in the orthogonal direction Y1.

[0060] In the conveying process, it is preferable to gradually increase the distance d between the pair of conveyor belts 50, 50 downstream in the conveying direction X1 so that the elongation rate of the filamentous elastic body 24 in the orthogonal direction Y1 is equal to the elongation rate of the filamentous elastic body 24 in the height direction Z. When the difference in elongation rates in the orthogonal direction Y1 and the height direction Z of the wound filamentous elastic body 24 is suppressed, the wound filamentous elastic body 24 becomes less likely to shift on the conveyor belt 50 (forward-moving portions 51a, 55a), and the pitch of the filamentous elastic body 24 becomes easier to maintain at a predetermined interval. This makes it possible to arrange the filamentous elastic body 24 in the stretchable sheet 21 at equal intervals, for example. From the viewpoint of more reliably achieving such effects, the difference between the elongation rate of the wound filamentous elastic body 24 in the orthogonal direction Y1 and the elongation rate of the filamentous elastic body 24 in the height direction Z is preferably 1.0 or less, more preferably 0.5 or less, and most preferably there is no difference between these elongation rates (it is 0). From the same viewpoint as above, it is preferable that the angle θ1 between the pair of conveyor belts 50, 50 in a plan view (see Figure 6) is greater than or equal to the angle θ2 between the upper belt 51 and the lower belt 55 in a side view (see Figure 5) (θ1 ≥ θ2). In this case, the difference between the angle θ1 between the pair of conveyor belts in a plan view (see Figure 6) and the angle θ2 between the upper belt 51 and the lower belt 55 in a side view (see Figure 5) is preferably 0° or more and 49° or less.

[0061] In the conveying process, from the viewpoint of making the filamentous elastic bodies 24 conveyed by the conveyor belt 50 more parallel, it is preferable to make the conveying speeds of the upper belt 51 and the lower belt 55 different in the conveying process, so that the orientation of the filamentous elastic bodies 24 fixed between the pair of continuous sheets 23a and 23b is parallel to or close to parallel with the orthogonal direction Y1. Specifically, by making the conveying speed of the upper belt 51 and the conveying speed of the lower belt 55 different, it is possible to make the filamentous elastic bodies 24 that are extended in the orthogonal direction Y1 adjacent to the conveying direction X1 parallel to or close to parallel. In this embodiment, the filamentous elastic bodies 24 stretched between the forward-moving portions 51a of the pair of upper belts and the filamentous elastic bodies 24 stretched between the forward-moving portions 55a of the pair of lower belts are adjacent to each other in the conveying direction X1.

[0062] From the viewpoint of more easily making adjacent filamentous elastic bodies 24 parallel in the conveying direction X1, it is preferable that the upper belt 51 of one conveying belt 50 has a faster conveying speed than the lower belt 55, and the upper belt 51 of the other conveying belt 50 has a slower conveying speed than the lower belt 55. In this case, it is preferable that the conveying speeds of the upper belt 51 and the lower belt 55 are within the following ranges. The difference in conveying speed between the upper belt 51 and the lower belt 55 is preferably 0.05 m / min or more and 20 m / min or less, more preferably 4 m / min or more and 14 m / min or less. The conveying speed of the upper belt 51 and the lower belt 55 is preferably 0.25 m / min or more and 100 m / min or less, more preferably 20 m / min or more and 70 m / min or less.

[0063] The integration process involves sandwiching the filamentous elastic body 24 in a transported state between a pair of continuous sheets 23a and 23b, thereby fixing the filamentous elastic body between the pair of continuous sheets 23a and 23b. The integration process is carried out while the wound filamentous elastic body 24 is transported by the integration means 6 described above. In the integration process of this embodiment, the portion of the filamentous elastic body 24 that extends in the orthogonal direction Y1 between a pair of transport belts 50, 50 is introduced into the pair of continuous sheets 23a and 23b. That is, the filamentous elastic body 24 stretched between the forward-moving portions 51a of a pair of upper belts and the filamentous elastic body 24 stretched between the forward-moving portions 55a of a pair of lower belts are introduced into the pair of continuous sheets 23a and 23b. In the integration process, a filamentous elastic body 24 is sandwiched between a pair of continuous sheets 23a and 23b to which adhesive has been applied, and this is pressed between a pair of nip rollers 61 and 62. As a result, the filamentous elastic body 24, which extends in a direction perpendicular to the extending direction of the pair of continuous sheets 23a and 23b, is intermittently fixed in that extending direction.

[0064] The cutting process is performed after the integration process and involves cutting the filamentous elastic material 24 extending from both ends of the continuous sheets 23a and 23b in the width direction (orthogonal direction Y1). The cutting process is performed by the cutting means 8 described above. The cutting process releases the filamentous elastic material 24 wound between the pair of conveyor belts 50, 50 from the conveyor belts 50, and a continuous stretchable sheet 22 is obtained.

[0065] The stretchable sheet continuous 22 obtained by the above fixing process is intermittently cut in the extending direction of the continuous 22 by a known cutting means (not shown). The interval between intermittent cuts can be, for example, the same dimension as the waist panel 20 of the diaper 1, thereby enabling the continuous production of waist panels 20 made of the stretchable sheet 21.

[0066] The manufacturing method of this embodiment can efficiently produce a wide, stretchable sheet 21 having a width (length in the orthogonal direction Y1) preferably of 160 mm or more by suppressing unintended cutting or vibration of the filamentous elastic body 24 in the aforementioned conveying process. The stretchable sheet 21 obtained by the manufacturing method of this embodiment has a width (length in the orthogonal direction Y1) preferably of 160 mm to 280 mm, more preferably of 200 mm to 240 mm.

[0067] Although the present invention has been described above based on its preferred embodiments, the present invention is not limited to the embodiments described above and can be modified as appropriate. For example, in the conveying process of the embodiment described above, the elongation rate of the wound filamentous elastic body 24 was gradually increased in both the height direction Z and the orthogonal direction Y1 toward the downstream direction X1 of the conveying direction. However, it is also possible to gradually increase only the elongation rate in the height direction Z. Furthermore, the conveying speeds of the upper belt 51 and the lower belt 55 may be set to be the same during the conveying process. Furthermore, the fixing process does not necessarily have to include an introduction process. Furthermore, in the above-described embodiment, the surfaces of the continuous sheets 23a and 23b were arranged so as to be parallel to the horizontal direction, but these surfaces may also be arranged so as to be parallel to the vertical direction. In the latter case, the height direction Z will be parallel to the horizontal direction. Furthermore, the upper and lower belts may not be arranged in two stages in the vertical direction Z, with the forward and reverse sections arranged in two stages in the orthogonal direction Y1. [Explanation of Symbols]

[0068] 1. Disposable diapers 11 Surface sheet 13 Back sheet 14 Absorbent 15 Absorbent body 16 Leak proof cuff 17 Cuff elastic member 18 Leg elastic members 19 Panel materials 20 Waist Panel 21 Stretchable Sheet 22 Extendable Sheet Continuum 23a, 23b Continuous Sheet 24. Filamentous elastic bodies 26 Fastening Tape 100 Manufacturing equipment 3. Introduction methods 30 Tension adjustment means 31 Feed Roller 32 Tension Sensor 35 Speed ​​adjustment means 36a, 36b Guide rollers 37 Feed Roller 4. Winding mechanism 40 Rotating Arm 41 Vertical section 42 Loop Section 42a outlet 43 Shaft section 47 Drive unit 48 Servo motors 49 Interlocking belt 5. Conveying means 50 Conveyor belts 51 Upper belt 51a forward running part 51b Reverse direction section 55 Lower belt 55a forward running part 55b Reverse section 52, 53, 56, 57 Pulley 59 Belt support guide 61, 62 Nip Roller 71a, 71b Adhesive application means A. Ventral part B Dorsal part C Inseam X vertical direction Y (horizontal direction) X1 Conveying direction Y1 orthogonal direction Z (height direction)

Claims

1. A method for manufacturing an elastic sheet, comprising a fixing step of fixing an elongated filamentous elastic body between a pair of continuous sheets while conveying the pair of continuous sheets and a filamentous elastic body along the conveying direction, The aforementioned fixing step is, An adhesive application step of applying adhesive to one or both of the pair of continuous sheets in the transport state, A winding step of continuously winding the filamentous elastic body around a pair of conveyor belts spaced apart in a direction perpendicular to the conveying direction, A conveying step in which the wound filamentous elastic body is conveyed in the conveying direction by the pair of conveying belts, An integration step in which the filamentous elastic body in the transport state is sandwiched between the pair of continuous sheets and the filamentous elastic body is fixed between the pair of continuous sheets, The process includes, after the integration step, a cutting step of cutting the filamentous elastic bodies extending from each of the widthwise ends of the continuous sheet, Each of the aforementioned pair of conveyor belts comprises an upper belt and a lower belt arranged in the height direction of the conveyor belt, A method for manufacturing an elastic sheet, wherein, in the conveying step, the elongation rate in the height direction of the wound filamentous elastic body is gradually increased toward the downstream direction of the conveying.

2. A method for manufacturing an elastic sheet according to claim 1, wherein in the conveying step, the elongation rate of the wound filamentous elastic body in the height direction and the elongation rate of the wound filamentous elastic body in the orthogonal direction are gradually increased toward the downstream direction of the conveying.

3. The winding process is performed by a winding means that continuously winds the filamentous elastic body onto the pair of conveyor belts. A method for manufacturing an elastic sheet according to claim 1 or 2, comprising: a tension adjustment step of adjusting the tension of the filamentous elastic body introduced into the winding means to a constant value before the winding step; and a speed adjustment step of adjusting the supply speed of the filamentous elastic body introduced into the winding means.

4. The method for manufacturing an expandable sheet according to claim 3, wherein the speed adjustment step involves passing the filamentous elastic body between a feed roller and a guide roller, and adjusting the supply speed by increasing or decreasing the rotational speed of the feed roller.

5. The method for manufacturing an elastic sheet according to claim 1 or 2, wherein in the conveying step, the conveying speeds of the upper belt and the lower belt are made different from each other, and the orientation of the filamentous elastic body fixed between the pair of continuous sheets is made parallel to or nearly parallel to the orthogonal direction.

6. A method for manufacturing an expandable sheet according to claim 1 or 2, wherein in the conveying step, the distance between the pair of conveying belts is gradually increased downstream in the conveying direction so that the elongation rate of the filamentous elastic body in the orthogonal direction is equal to the elongation rate of the filamentous elastic body in the height direction.

7. An apparatus for manufacturing stretchable sheets, which transports a pair of continuous sheets and a filamentous elastic body along the transport direction, and fixes the stretched filamentous elastic body between the pair of continuous sheets, The system comprises: an adhesive application means for applying adhesive to one or both of the pair of continuous sheets in a transport state; a pair of transport belts spaced apart in an orthogonal direction perpendicular to the transport direction; a winding means for continuously winding the filamentous elastic body around the pair of transport belts; an integrating means for fixing the wound filamentous elastic body between the pair of continuous sheets; and a cutting means for cutting the filamentous elastic body extending from each of the widthwise ends of the continuous sheets. A manufacturing apparatus for stretchable sheets, wherein each pair of conveyor belts comprises an upper belt and a lower belt arranged in the height direction of the conveyor belt, and the distance between the upper belt and the lower belt gradually increases toward the downstream direction of conveying.

8. The manufacturing apparatus for stretchable sheets according to claim 7, wherein the distance between a pair of conveyor belts in a plan view also gradually increases toward the downstream direction of conveyance.

9. An apparatus for manufacturing an elastic sheet according to claim 7 or 8, further comprising, upstream of the winding means in the transport direction, tension adjusting means for adjusting the tension of the filamentous elastic body before it is introduced into the winding means to a constant level, and speed adjusting means for adjusting the supply speed of the filamentous elastic body to the winding means.

10. The apparatus for manufacturing an expandable sheet according to claim 7 or 8, wherein the conveying belt is controllable so that the conveying speeds of the upper belt and the lower belt are different from each other.

11. The apparatus for manufacturing an expandable sheet according to claim 7 or 8, wherein the angle θ1 between the pair of conveyor belts in a plan view is greater than or equal to the angle θ2 between the upper belt and the lower belt in a side view.

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