JP2012120571A - Method for manufacturing stretchable sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a stretchable sheet, enabling the stable manufacture of a stretchable sheet having thread-like elastic bodies partially different in extension scaling factor by partially changing the extension scaling factor of the thread-like elastic bodies to be introduced.SOLUTION: This method for manufacturing a stretchable sheet is a method for continuously manufacturing a stretchable sheet in which a thread-like elastic body 7 is fixed between strip-shaped sheets 50, 60 in a state that it extends in a direction crossing a y-direction. This method includes: a supply step of introducing the thread-like elastic body 7 into an elastic body winding means 14; a transfer step of continuously winding the thread-like elastic body 7 around thread-transfer longitudinal structures 12, 13 by using the elastic body winding means 14, and transferring the wound thread-like elastic body 7; and an integrating step of fixing the thread-like elastic body 7 between the sheets 50, 60. In the supply step, the introduction velocity at which the thread-like elastic body 7 is introduced in the elastic body winding means 14 is controlled to manufacture the stretchable sheet having the thread-like elastic body 7 partially different in expansion scaling factor.

Description

  The present invention relates to a method for producing an elastic sheet.

  From the standpoint of saving materials as much as possible, reducing waste as much as possible, environmentally friendly, and reducing costs, a waist panel material with fastening tape is manufactured in a separate process, and the rectangular absorbency including the absorber An unfolded disposable diaper manufactured by adding this waist panel material to a main body is known. The waist panel material is preferably a stretchable member from the viewpoint of wearability, and the waist panel material is generally formed using a stretchable film. However, since a stretchable film is expensive, it is preferable to form a waist panel material using a so-called thread rubber that is a general-purpose elastic member. However, when the process of obtaining the waist panel material using the rubber thread and the process of adding the waist panel material to the absorbent main body to obtain the deployable disposable diaper are continuously performed in a series of flows, the rubber thread is used. The stretch direction of the waist panel material formed by using is generally the same direction as the transport direction of the absorbent main body, and is a direction orthogonal to the stretch direction of the waist panel material required when the unfolded disposable diaper is worn. Therefore, when manufacturing a deployable disposable diaper by adding a waist panel material formed using thread rubber to the absorbent main body in an in-line process, the waist panel material formed using thread rubber is inverted 90 degrees and absorbed. It is necessary to add to the sex body. Thus, since the apparatus which reverses a waist panel material 90 degree | times is needed separately, an increase in capital investment will be caused.

  As a method that does not use the 90-degree reversing apparatus as described above, for example, in Patent Document 1 and Patent Document 2, an adhesive is applied to a water-permeable sheet that is running in the length direction, and the adhesive-coated surface is applied. A step of translating a tensioned thread-like elastic body in a zigzag state along the sheet surface of the traveling sheet and in the sheet traveling direction, and bonding the thread-like elastic body to the sheet in an extended state; The manufacturing method of the elastic sheet which performs the process of cut | disconnecting the said thread-like elastic body at both ends is described. Patent Document 1 also describes a method of rearranging the zigzag thread-like elastic bodies in parallel.

  However, as in Patent Documents 1 and 2, the thread-like elastic body is wound around a pair of feed belts and oriented in a direction crossing the sheet conveying direction, and the thread-like elastic body in that state is integrated with the sheet to expand and contract. In the method of obtaining the elastic sheet, unlike the case where the thread-like elastic body introduced along the sheet conveying direction is fixed to the sheet, the expansion rate of the thread-like elastic body to be introduced is partially changed to It was difficult to produce stretchable sheets with partially different stretch ratios.

Japanese Unexamined Patent Publication No. 63-243309 JP 2010-22588 A

  Therefore, the subject of this invention is providing the manufacturing method of the elastic sheet which can eliminate the fault which the prior art mentioned above has.

  The present invention is a method for producing a stretchable sheet for continuously producing a stretchable sheet in which a thread-like elastic body is stretched between a pair of beltlike sheets in a direction extending in a direction intersecting the transport direction of the beltlike sheet. A feeding step of continuously feeding out the thread-like elastic body, introducing the fed-out thread-like elastic body into the elastic body winding means, and using the elastic body winding means, An integral process for continuously winding the thread-like elastic body around the structure and transporting the wound thread-like elastic body in the longitudinal direction of the longitudinal structure for thread transportation, and fixing the transported thread-like elastic body between sheets In the supplying step, the rate of introduction of the thread-like elastic body to be introduced into the elastic body winding means is controlled to produce a stretchable sheet having a partially different expansion ratio of the thread-like elastic body Providing a method for producing a stretchable sheet A.

  According to the method for producing a stretchable sheet of the present invention, the stretch magnification of the thread-like elastic body to be introduced can be partially changed, and a stretchable sheet having a partially different stretch magnification of the thread-like elastic body is stably produced. A method for producing a stretchable sheet is provided.

FIG. 1 is a plan view showing a waist panel material and a deployable disposable diaper obtained by an embodiment of the present invention. FIG. 2 is a perspective view showing a stretchable sheet manufacturing apparatus suitably used for carrying out the manufacturing method of one embodiment of the present invention. FIG. 3 is a perspective view showing a configuration upstream of the rotary arm (elastic body winding means) of the apparatus shown in FIG. FIG. 4A is an explanatory diagram showing a change in the introduction speed of the filamentous elastic body, and FIG. 4B is an explanatory diagram showing a change in the introduction amount of the filamentous elastic body.

Hereinafter, the manufacturing method of the elastic sheet of this invention is demonstrated, referring drawings based on the preferable embodiment.
As shown in FIG. 1, the stretchable sheet manufactured in the present embodiment is used for, for example, the waist panel 3 of the unfolded disposable diaper 1. Therefore, first, the unfoldable disposable diaper 1 using the stretchable sheet manufactured according to this embodiment for the waist panel will be described.

As shown in FIG. 1, the unfoldable disposable diaper 1 (hereinafter also referred to as “diaper 1”) includes a ventral side A located on the abdomen side of the wearer and a dorsal side B positioned on the dorsal side when worn. , And an absorbent main body 2 having a crotch C positioned between the abdominal side A and the back side B, and a pair of left and right waist panels 3, 3 connected to the left and right outside of the back side B And have. As shown in FIG. 1, the diaper 1 has a pair of left and right panel members 4, 4 connected to the left and right outer sides of the ventral side A. In addition, as shown in FIG. 1, the absorptive main body 2 of the diaper 1 has a rectangular shape in a state of being expanded in a planar shape. Moreover, as shown in FIG. 1, the panel material 4 of the diaper 1 has a trapezoidal shape in a state of being spread in a flat shape, and the lower bottom side having a long length is formed by an absorbent body or an adhesive body by means such as adhesive or fusion. 2 is fixed.
In the following description, the longitudinal direction of the absorbent main body 2 (also the longitudinal direction of the diaper 1) will be described as the Y direction, and the width direction of the absorbent main body 2 (also the width direction of the diaper 1) will be described as the X direction.

  Each of the pair of waist panels 3 and 3 has a rectangular shape in a state of being expanded in a planar shape. Each waist panel 3 has two sheets 5, 6 and a plurality of thread-like elastic bodies 7 arranged between the two sheets 5, 6 in an extended state. Each waist panel 3 is made of a stretchable sheet that is fixed between a pair of sheets 5 and 6 in a state where the thread-like elastic body 7 extends in a direction intersecting the Y direction. Specifically, as shown in FIG. 1, each waist panel 3 extends in a direction (X direction) orthogonal to the Y direction between two rectangular sheets 5 and 6 having the same shape and the same size. The thread-like elastic bodies are formed at substantially equal intervals in the Y direction and integrally fixed by means such as an adhesive or fusion. A fastening tape 8 is fixed to the rectangular waist panel 3 formed in this way at an end portion on the outer side in the X direction by means such as adhesive or fusion. The rectangular waist panel 3 is fixed to the back side B of the absorbent main body 2 by means such as adhesive or fusion, and the X side inward in the X direction. It is connected to the direction. In addition, although the threadlike elastic body 7 which the waist panel 3 (elastic sheet) manufactured by this embodiment has extended | stretched in the direction orthogonal to a Y direction, if extended | stretched in the direction which cross | intersects the Y direction, Good.

  As shown in FIG. 1, each of the pair of waist panels 3 and 3 includes a plurality of thread-like elastic bodies 7 disposed in a region D to which the fastening tape 8 is attached, and a fastening tape 8 closer to the crotch C side than the region D. Are formed of a plurality of thread-like elastic bodies 7 arranged in the region F where no fastening tape 8 is attached and a plurality of thread-like elastic bodies 7 arranged in the region E where the remaining fastening tape 8 is not attached. Here, in the waist panel 3 manufactured in the present embodiment, the expansion ratio of the filamentous elastic body 7 disposed in the region D is disposed in the expansion magnification of the filamentous elastic body 7 disposed in the region E and the region F. It is higher than each expansion ratio of the thread-like elastic body 7. That is, the contraction force of the thread-like elastic body 7 disposed in the region D is stronger than the contraction force of the thread-like elastic body 7 disposed in the region E and the contraction force of the thread-like elastic body 7 disposed in the region F. Yes. Therefore, the diaper 1 can be firmly fixed around the wearer's waist by engaging the fastening tape 8 with the panel material 4.

  As shown in FIG. 1, the absorbent main body 2 includes a liquid-permeable top sheet 21, a liquid-impermeable or water-repellent back sheet 22, and a liquid-retaining property interposed between the two sheets 21 and 22. And an absorber 23. As shown in FIG. 1, the absorbent main body 2 includes a top sheet 21 that forms the inner surface of the diaper 1 and a back sheet 22 that forms the outer surface of the diaper 1, with an absorber 23 interposed between the two sheets 21 and 22. It is formed by joining. Moreover, the absorptive main body 2 is provided with three-dimensional guard forming sheets 24, 24 along both sides in the Y direction, as shown in FIG. The three-dimensional guard forming sheet 24 is fixed to the topsheet 21 along both sides in the Y direction of the absorbent main body 2. Each three-dimensional guard forming sheet 24 has a three-dimensional guard-forming elastic member 25 along the vicinity of the inner edge on the inner side in the X direction. A portion having a predetermined width is separated from the top sheet 21 to form a three-dimensional guard. Moreover, the elastic member 26 for leg gather formation is distribute | arranged to the part distribute | arranged around the leg of the longitudinal direction both sides of the absorptive main body 2. At the time of wearing, a leg gather is formed by the contraction of the elastic member 26 and fits well around the legs.

The material for forming the diaper 1 will be described.
As the sheet | seats 5 and 6 and the panel material 4 which comprise the waist panel 3, if normally used for absorbent articles, such as a disposable diaper, it can use without a restriction | limiting especially. For example, as the sheets 5 and 6 and the panel material 4, a non-woven fabric, a woven fabric, a film, or a laminated sheet thereof can be used. As the surface sheet 21 and the back surface sheet 22 constituting the absorbent main body 2, as long as they are usually used for absorbent articles such as disposable diapers, they can be used without particular limitation. For example, a hydrophilic and liquid-permeable non-woven fabric can be used as the top sheet 21, and a liquid-impermeable or water-repellent resin film or a laminate of a resin film and a non-woven fabric is used as the back sheet 22. be able to. As the absorbent body 23, an aggregate of fibers such as pulp fibers (may be a non-woven fabric) or an absorbent core in which water-absorbing polymer particles are held therein, a core wrap made of water-permeable thin paper or non-woven fabric. What was covered with the sheet | seat etc. can be used. As the three-dimensional guard forming sheet 24 constituting the three-dimensional guard, a stretchable film, a nonwoven fabric, a woven fabric, or a laminated sheet thereof can be used. Examples of the elastic member 25 constituting the thread-like elastic body 7 and the three-dimensional guard include natural rubber, polyurethane, polystyrene-polyisoprene copolymer, polystyrene-polybutadiene copolymer, and polyethylene-α-olefin copolymer such as ethyl acrylate-ethylene. A thread-like stretchable material made of, for example, can be used. The filamentous elastic body in the present invention includes not only those having a circular or square cross section but also those having a narrow band shape such as an ellipse or a rectangular cross section, and a multifilament type can also be used. The width | variety (or diameter) of a thread-like elastic member is 0.1-3 mm, for example, Preferably it is 1 mm or less. As the fastening tape 8, for example, a tape formed by attaching a hook member of a mechanical fastener to one surface of a tape base material such as a nonwoven fabric by heat fusion or an adhesive can be used.

Next, the preferable embodiment of the manufacturing method of the elastic sheet of this invention is demonstrated, referring an example for the case where the waist panel 3 (elastic sheet) of the diaper 1 mentioned above is manufactured.
FIG. 2 schematically shows a production apparatus suitably used in the method for producing the waist panel 3 (elastic sheet) of this embodiment.

As shown in FIG. 2, the manufacturing apparatus 11 is an apparatus that continuously manufactures an elastic sheet used for the waist panel 3, and is separated in a direction (x direction) orthogonal to the sheet conveyance direction (y direction). The pair of transport belts 12 and 13 is provided with a rotating arm (elastic body winding means) 14 for winding an elastic body for continuously winding the thread-like elastic body 7. Further, as shown in FIGS. 2 and 3, the manufacturing apparatus 11 continuously feeds the thread-like elastic body 7 and introduces the thread-like elastic body 7 into the rotating arm 14 in an extended state. A conveying means 16 that conveys the thread-like elastic body 7 between the pair of belt-like sheets 50 and 60 by the pair of conveyor belts 12 and 13 and a pair of nip rollers 171 and 172 between the pair of belt-like sheets 50 and 60. This embodiment includes an integration means 17 for fixing the elongated thread-like elastic body 7 and a cutting means 18 for cutting the thread-like elastic body 7 extending from both ends of the belt-like sheets 50 and 60 in the width direction. , The pair of conveyor belts 12 and 13 is the longitudinal structure for yarn conveyance in the present invention, and the longitudinal direction of the longitudinal structure for yarn conveyance is the extending direction of both the conveyor belts 12 and 13 (y direction). It is.

The conveyance direction of the sheet is the conveyance direction of the thread-like elastic body 7 wound around the pair of conveyance belts 12 and 13 or the conveyance direction of the sheet integrated with the thread-like elastic body 7 (band-like sheets 50 and / or 60). is there.
The y direction of the arrow in FIG. 2 indicates the conveyance direction of the thread-like elastic body 7 and the pair of belt-like sheets 50 and 60, which is the sheet conveyance direction, and finally the waist panel 3 (stretchable) manufactured according to this embodiment. The conveying direction of the sheet) and the conveying direction of the continuous body of the diaper 1 to which the waist panel 3 (elastic sheet) is attached are the same direction.
Also, the x direction of the arrow in FIG. 2 is the width direction of the belt-like sheets 50 and 60, and is the direction orthogonal to the sheet conveying direction. 2 is a direction in which a pair of nip rollers 171 and 172 described later face each other.

  As shown in FIG. 2, the conveyor belt 12 of the conveyor means 16 is an endless rotating belt, and includes an upper conveyor belt 12a and a lower conveyor belt 12b. The upper conveyance belt 12a is stretched between pulleys 121 and 122 whose rotation axis direction is arranged in the z direction. The lower conveyance belt 12b is bridged between pulleys 124 and 125 whose rotation axis direction is arranged in the z direction. The pulley 121 is located on the downstream side of the pair of nip rollers 171 and 172 for fixing the elongated thread-like elastic body 7 between the pair of belt-like sheets 50 and 60, and the pulley 122 is located on the upstream side of the nip rollers 171 and 172. Is located. The pulley 124 is located on the downstream side of the nip rollers 171 and 172, and the pulley 125 is located on the upstream side of the nip rollers 171 and 172. The pulleys 121 and 124 are arranged at the same position in two upper and lower stages. Further, the rollers 122 and 125 are also arranged in two upper and lower stages at the same position. Further, the pulley 121 (pulley 124) and the pulley 122 (pulley 125) are located outward in the x direction from the x direction end portions of the belt-like sheets 50 and 60. Each of the pulley 121 and the pulley 124 is provided with a servo motor (not shown) connected to its drive unit, so that the rotational speeds of the upper conveyance belt 12a and the lower conveyance belt 12b can be changed.

  As shown in FIG. 2, the conveyance belt 13 of the conveyance means 16 is an endless rotating belt, similar to the conveyance belt 12, and includes an upper conveyance belt 13a and a lower conveyance belt 13b. The upper conveyance belt 13a is stretched between pulleys 131 and 132 whose rotation axis direction is arranged in the z direction. The lower conveyance belt 13b is bridged between pulleys 134 and 135 whose rotation axis direction is arranged in the z direction. The pulley 131 is located on the downstream side of the pair of nip rollers 171 and 172, and the pulley 132 is located on the upstream side of the nip rollers 171 and 172. The pulley 134 is located on the downstream side of the nip rollers 171 and 172, and the pulley 135 is located on the upstream side of the nip rollers 171 and 172. The pulleys 131 and 134 are arranged in two upper and lower stages at the same position. Further, the pulleys 132 and 135 are also arranged in two upper and lower stages at the same position. Further, the pulley 131 (pulley 134) and the pulley 132 (pulley 135) are located outward in the x direction from the x direction ends of the belt-like sheets 50 and 60. Each of the pulley 131 and the pulley 134 is provided with a servo motor (not shown) connected to its drive unit, and the rotational speed of each of the upper conveyance belt 13a and the lower conveyance belt 13b can be changed.

As shown in FIG. 2, the conveyor belt 12 (the upper conveyor belt 12 a and the lower conveyor belt 12 b) is bridged between the pulleys 121 and 122 and the pulleys 124 and 125 arranged as described above, and the pair of nip rollers 171. , 172 from the upstream side to the downstream side. Further, the conveyor belt 13 (the upper conveyor belt 13a and the lower conveyor belt 13b) is stretched over the pulleys 131 and 132 and the pulleys 134 and 135 arranged as described above, and the upstream side of the pair of nip rollers 171 and 172. To the downstream side. Further, the transport belt 12 (upper transport belt 12a and lower transport belt 12b) and the transport belt 13 (upper transport belt 13a and lower transport belt 13b) are located outside the belt-like sheets 50 and 60 in the x direction and are symmetrical with each other. It is arranged in. The transport belt 12 (upper transport belt 12a, lower transport belt 12b) and transport belt 13 (upper transport belt 13a, lower transport belt 13b) rotate so that their outer peripheral sides move in the y direction.
The transport belt 12 (upper transport belt 12a, lower transport belt 12b) and transport belt 13 (upper transport belt 13a, lower transport belt 13b) are preferably timing belts. The rotational speeds of the transport belt 12 (upper transport belt 12a, lower transport belt 12b) and transport belt 13 (upper transport belt 13a, lower transport belt 13b), that is, the driving units of the pulley 121 and pulley 124, and the pulley 131 and pulley 134, respectively. The rotation speed of a servo motor (not shown) arranged in the control unit is controlled by a control unit (not shown) included in the manufacturing apparatus 11.

  As shown in FIG. 2, the rotating arm 14 includes an arm portion 141 having a shaft portion 142, a revolving portion 143, and a connecting portion 144, and a drive mechanism 147 that rotates the arm portion 141 around the center line of the shaft portion 142. And. The connecting portion 144 is coupled to each of the shaft portion 142 and the rotating portion 143 at an angle, and the rotating portion 143 and the shaft portion 142 are substantially parallel. The shaft portion 142 has an introduction port 145 for the thread-like elastic body 7 at one end thereof, and the circumferential portion 143 has a lead-out port 146 for the thread-like elastic body 7 at one end thereof, which is introduced from the introduction port 145. The thread-like elastic body 7 is smoothly led out from the outlet port 146 through the shaft portion 142, the connecting portion 144 and the rotating portion 143. Various known members (a driven roll, a low friction member, etc.) that can reduce friction with the thread-like elastic body 7 can be disposed in the bent portion of the arm portion 141, the outlet port 146, and the like.

In the circulation part 143, the position of the outlet 146 is downstream from the upstream end of the transport belt 12 (upper transport belt 12a, lower transport belt 12b) and transport belt 13 (upper transport belt 13a, lower transport belt 13b). It is arranged in. The rotary arm 14 has a servo motor 148 attached to its drive part (shaft part 142), and the rotation part 143 causes the rotation part 143 to move the conveyor belt 12 (the upper conveyor belt 12a and the lower conveyor belt 12b) by the rotation of the servo motor 148. And the outer circumference of the conveyor belt 13 (the upper conveyor belt 13a and the lower conveyor belt 13b) is circulated. The diameter of the locus along which the outlet 146 rotates is greater than the distance between the outer surfaces of the pair of conveyor belts 12 and 13.
By such a rotating arm 14, the thread-like elastic body 7 taken in is fed to the upstream end of the transport belt 12 (upper transport belt 12a, lower transport belt 12b) and transport belt 13 (upper transport belt 13a, lower transport belt 13b). It is a part and can be continuously wound on each outer peripheral side. The rotation speed of the rotary arm 14, that is, the rotation speed of the servo motor 148 is controlled by a control unit (not shown) included in the manufacturing apparatus 11.

As shown in FIG. 3, the elastic body supply means 15 includes means for pulling out the thread-like elastic body 7 from the bobbin 70, tension adjusting means 15A for applying a predetermined tension to the thread-like elastic body 7 drawn out from the bobbin 70, and tension adjustment. A speed adjusting means 15B for adjusting the speed of the thread-like elastic body 7 fed from the tension adjusting means 15A and introducing it into the rotating arm (elastic body winding means) 14 is provided downstream of the means 15A. Yes.
The tension adjusting means 15 </ b> A is located on the downstream side of the bobbin 70, the tensioner 151 for applying tension to the thread-like elastic body 7 by the brake, the feeding roller 152 located on the downstream side of the tensor 151, and the downstream side of the feeding roller 152. And a tension measuring device 153. The feeding roller 152 has a rotational axis direction in the x direction. A servo motor (not shown) is attached to the driving portion of the feeding roller 152. The feeding roller 152 is used with the thread-like elastic body 7 wound around its outer periphery once or a plurality of times (preferably twice). The feeding roller 152 used in this embodiment also serves as the whole or a part of the above-mentioned drawing means, and the thread-like elastic body 7 drawn from the bobbin 70 by the drawing roller 152 passes through the guide hole of the guide member 150. Are introduced into the tensor 151.

  The tension adjusting unit 15A detects the tension of the thread-like elastic body 7 between the feeding roller 152 and the guide roller 155 by the tension measuring device 153, and the tension measuring device 153 by a control unit (not shown) included in the manufacturing apparatus 11. The rotational speed of the feeding roller 152 is controlled by the foot back based on the detection output from the. Thereby, the tension of the thread-like elastic body 7 sent out from the guide roller 155 can be adjusted to the set predetermined tension.

The speed adjusting means 15B adjusts the speed of the thread-like elastic body 7 sent out from the tension adjusting means 15A, and introduces the speed-adjusted thread-like elastic body 7 into the rotating arm (elastic body winding means) 14. As shown in FIG. 3, the speed adjusting unit 15 </ b> B includes a feed roller 156 in the vicinity of the rotating arm 14. The feed roller 156 is disposed between the rotating arm 14 and the feeding roller 152, and the rotation axis direction thereof is disposed in the x direction. Guide rollers 156a and 156b are arranged before and after the feed roller 156. The feed roller 156 has a servo motor (not shown) attached to its drive unit. The rotation speed of the servo motor (not shown), that is, the rotation speed of the feed roller 156 is controlled by a control unit (not shown) provided in the manufacturing apparatus 11.
It is preferable that the feed roller 156 is disposed in the vicinity of the rotating arm 14, particularly immediately before the feed path of the thread-like elastic body. For example, the length of the conveyance path of the thread-like elastic body from the time when it leaves the feed roller 156 until it is introduced into the rotation arm 14 is 10 times the total length of the conveyance path of the thread-like elastic body from the bobbin 70 to the rotation arm 14. It is preferably ˜50%, more preferably 10 to 30%.

  As shown in FIG. 2, the integration unit 17 includes a pair of nip rollers 171 and 172. As the pair of nip rollers 171, 172, a metal cylindrical roller or a cylindrical roller made of low hardness silicon rubber can be used. The pair of nip rollers 171 and 172 has a servo motor (not shown) attached to one of the drive units, and the rotation speed is controlled by a control unit (not shown) included in the manufacturing apparatus 11. Drive transmission gears are attached to the rotation shafts of the pair of nip rollers 171 and 172, respectively. By this driving means (not shown), the rotation speed of a servo motor (not shown), that is, the rotation speed of one of the nip rollers 171 and 172 can be controlled based on the production speed of the stretchable sheet. At this time, when the drive transmission gear is engaged, the driving force is transmitted to the other nip rollers 172 and 171, and the pair of nip rollers 171 and 172 can be rotated. The bearing portions of the pair of nip rollers 171 and 172 use a force such as hydraulic pressure, pneumatic pressure, or spring in order to securely fix the elongated elastic body between the pair of belt-like sheets 50 and 60, Each bearing part is pressurized.

  As shown in FIG. 2, the pair of nip rollers 171 and 172 includes an inner peripheral side of the transport belt 12 (upper transport belt 12a and lower transport belt 12b) and a transport belt 13 (upper transport belt 13a and lower transport belt 13b). It is located between the inner circumference side.

  As shown in FIG. 2, the cutting means 18 includes a cutter 180 in which a portion to which the conveyed elastic elastic body 7 contacts is a sharp cutting blade (the cutter 180 on the conveyance belt 13 side is not shown). The cutter 180 is disposed by a support (not shown) at a position where the thread-like elastic body 7 hits, and the thread-like elastic body 7 is cut by being conveyed by the conveyor belts 12 and 13 and being pressed against the cutter 180. . In the y direction, the cutting means 18 includes a pair of nip rollers 171, 172, pulleys 121, 124 of the conveyor belt 12 (upper conveyor belt 12a, lower conveyor belt 12b), and conveyor belt 13 (upper conveyor belt 13a, lower conveyor). It is located between the pulleys 131 and 134 of the belt 13b). The position in the x direction where the thread-like elastic body 7 is cut by the cutting means 18 may be between the nip rollers 171 and 172 and the conveyor belts 12 and 13, or the inner and outer circumferences of the conveyor belts 12 and 13, respectively. May be between the outer peripheral portions of the conveyor belts 12 and 13. As the cutting means 18, various known ones that can cut the thread-like elastic body 7 can be used without particular limitation. For example, a cutter roller having a cutting blade extending in the circumferential direction on the outer peripheral surface and the cutting blade It is also possible to use a roller cutter or the like equipped with an anvil roller for receiving the same. Moreover, you may cut | disconnect with a laser, a heat | fever, etc.

  Next, a method for manufacturing a stretchable sheet using the manufacturing apparatus 11 described above will be described.

First, as shown in FIG. 3, the thread-like elastic body 7 is continuously fed out, and the fed-out thread-like elastic body 7 is introduced into a rotating arm 14 as an elastic body winding means in a stretched state (supplying step). In the supply step, the introduction speed of the thread-like elastic body 7 introduced into the rotary arm 14 is controlled.
More specifically, the thread-like elastic body 7 is continuously pulled out from the bobbin 70 using the feeding roller 152. Then, a predetermined tension is applied to the thread-like elastic body 7 drawn out from the bobbin 70 by the tension adjusting means 15A. More specifically, the tension measuring device 153 detects the tension of the thread-like elastic body 7 between the feeding roller 152 and the guide roller 155, and the tension measuring device 153 is controlled by a control unit (not shown) included in the manufacturing apparatus 11. The rotational speed of the feeding roller 152 and the brake of the tensor 151 are adjusted on the basis of the detected output from the threaded elastic body 7 adjusted to a predetermined tension (predetermined expansion ratio) from the guide roller 155 toward the downstream side. Send it out. It should be noted that the brake of the tensor 151 is provided so that the sudden slack of the thread-like elastic body that may occur when the tensor 151 is pulled out from the bobbin 70 does not affect the downstream process.

  Then, the thread-like elastic body 7 is introduced into the rotary arm 14. When the thread-like elastic body 7 is introduced, the thread-like elastic body 7 stretched to a predetermined tension (a predetermined stretching magnification) by the tension adjusting means 15A described above is introduced. The speed adjusting means 15B supplies the rotating arm 14 while controlling the introduction speed. In the manufacturing apparatus 11, the introduction speed of the thread-like elastic body 7 is controlled by a feed roller 156 arranged on the upstream side of the rotating arm 14. Specifically, in the manufacturing apparatus 11, the rotation speed of the feed roller 156 is controlled by a control unit (not shown), and as shown in FIG. 4A, in the region E (see FIG. 1) of the waist panel 3. The thread-like elastic body 7 disposed in the corresponding part is introduced into the rotary arm 14 at the introduction speed V1, and the thread-like elastic body 7 disposed in the part corresponding to the region D (see FIG. 1) of the waist panel 3 is introduced at the introduction speed V1. The thread-like elastic body 7 which is introduced into the rotary arm 14 at a slower introduction speed V2 and is arranged in a portion corresponding to the region F of the waist panel 3 (see FIG. 1) is placed in the region B of the waist panel 3 (see FIG. 1). The introduction speed of the thread-like elastic body 7 is controlled so that the thread-like elastic body 7 is introduced into the rotary arm 14 at the same introduction speed V1 as the introduction speed V1 of the arranged thread-like elastic body 7. Thereafter, the rotational speed of the feed roller 156 is controlled so as to repeat the order of the introduction speed V1, the introduction speed V2, and the introduction speed V1, and the thread-like elastic body 7 is supplied to the rotary arm 14. Note that tD in FIG. 4A indicates the time required for the thread-like elastic body 7 to be wound around the pair of transport belts 12 and 13 by the rotating arm 14 (elastic body winding means).

A preferable range of the expansion ratio of the thread-like elastic body 7 whose tension is adjusted by the tension adjusting means 15A is 1.5 to 4.0 times, more preferably 1.8 to 3.5 times.
The expansion ratio is obtained by the following formula.

Elongation magnification = (Length of stretched filamentous elastic body) ÷ (Length of unstretched filamentous elastic body (natural length of filamentous elastic body))

A thread-like elastic body in the regions E and F of the stretchable sheet (waist panel 3) to be manufactured, in which the tension is adjusted by the tension adjusting means 15A and the tension is adjusted by controlling the rotation speed of the feed roller 156 of the speed adjusting means 15B. The preferable range of the expansion ratio of 7 is 1.5 to 3.0, and the preferable range of the expansion ratio of the thread-like elastic body 7 in the region D in the stretchable sheet (waist panel 3) to be manufactured is 2.0. -4.0 times.
The extension magnification is determined by the relationship between the introduction speed and the winding speed of the rotating arm 14 if the slipping of the thread-like elastic body 7 by the tension adjustment means 15A and the speed adjustment means 15B is ignored. The relationship with the introduction speed of the filamentous elastic body for obtaining the expansion ratio is expressed by the following equation.

Introduction speed = (winding speed of the rotating arm 14) / (stretching magnification) × correction coefficient

The introduction speed is a speed at which the thread-like elastic body 7 is introduced into the rotary arm 14 and is equivalent to the rotation speed of the feed roller 156, and can be rewritten as the following relational expression.

Rotation speed of feed roller 156 = (winding speed of rotating arm 14) / (stretching magnification) × correction coefficient

That is, when the winding speed of the rotary arm 14 is constant, the speed of the feed roller 156 is decreased to increase the expansion ratio of the thread-like elastic body 7, and conversely, the feed roller 156 is decreased to decrease the expansion ratio. The stretching magnification can be controlled by increasing the speed.
Here, the correction coefficient in the equation is a proportional coefficient that represents the relationship between the desired expansion ratio, the speed of the feed roller 156, and the speed of the rotary arm 14, and can be obtained in advance by experiments. For example, it is possible to obtain a regression line from the expansion ratio of the filamentous elastic body 7 when the speed of the rotating arm 14 is constant and the speed of the feed roller 156 is changed, and the slope of the regression line can be used as a correction coefficient.

  As for the rotational speed of the feed roller 156, it is desirable to determine a speed pattern for one elastic sheet (waist panel 3) to be manufactured in advance. An abrupt change in speed leads to breakage of the thread-like elastic body 7 being manufactured, which may hinder stable manufacture. For example, as shown in FIG. 4A, in the portion corresponding to the regions E and F of the waist panel 3, the rotation speed of the feed roller 156 is set to a constant speed V1, and the region corresponding to the region D of the waist panel 3 where the expansion magnification is increased. In the portion, the rotational speed is gradually decreased from the speed V1 to the speed V2, and when the rotational speed reaches the speed V2, the rotational speed is gradually increased from the speed V2 to the speed V1. By changing the rotation speed of the feed roller 156 in this way, the amount of introduction of the thread-like elastic body 7 is constant in the areas E and F as shown in FIG. Since the introduction amount of the thread-like elastic body 7 gradually increases after the introduction amount of the body 7 decreases, the expansion ratio of the thread-like elastic body 7 gradually changes in the same manner, and the thread-like elastic body 7 being manufactured is changed. The stretchable sheet (waist panel 3) is less likely to be cut and can be manufactured stably. Here, the “introduced amount of the thread-like elastic body 7” means that the nip roll 156 is wound while one thread-like elastic body 7 is wound by the rotating arm (elastic body winding means) 14 (corresponding to a half circumference of the rotating arm 14). This means the length of the thread-like elastic body 7 supplied to the inlet 145 of the rotary arm 14.

  After the supplying step, as shown in FIGS. 2 and 3, the elongated thread-like elastic body 7 is continuously wound around the pair of conveying belts 12 and 13 using the rotating arm 14, and the wound thread-like elastic body 7 is wound. Is conveyed in the longitudinal direction (y direction) of the pair of conveying belts 12 and 13 (conveying step). It is preferable that the rotation speed of the rotary arm 14 in the transfer process is constant. The thread-like elastic body 7 supplied into the rotating arm 14 in the extended state is introduced from the introduction port 145 into the arm portion 141, passes through the shaft portion 142, the connecting portion 144, and the revolving portion 143, and from the outlet port 146. Derived. The thread-like elastic body 7 led out from the lead-out port 146 is led out while the rotary arm 14 is rotated, so that the outer peripheral side at the upstream end of the transport belt 12 (upper transport belt 12a, lower transport belt 12b) and The conveyor belt 13 (upper conveyor belt 13a, lower conveyor belt 13b) is wound around the outer peripheral side at the upstream end. Here, the conveyor belt 12 (upper conveyor belt 12a, lower conveyor belt 12b) and the conveyor belt 12 (upper conveyor belt 12a, lower conveyor belt 12b) are rotated by the rotational travel of the conveyor belt 12 (upper conveyor belt 12a, lower conveyor belt 12b). ) And the outer periphery of the conveyor belt 13 (upper conveyor belt 13a, lower conveyor belt 13b), the thread-like elastic body 7 is continuously wound in a spiral shape. The continuously wound thread-like elastic body 7 is conveyed between the pair of downstream belt-like sheets 50 and 60.

  Here, the thread-like elastic body 7 wound around the pair of conveying belts 12 and 13 extends in a direction intersecting with the y direction, and is not arranged in a direction orthogonal to the y direction. In order to correct the wound elastic body 7 in a direction (x direction) orthogonal to the y direction, for example, when the elastic thread 7 is wound as shown in FIG. 12, the rotational speed of the upper transport belt 12 a is made slower than the rotational speed of the lower transport belt 12 b, and the rotational speed of the lower transport belt 13 b is made slower than the rotational speed of the upper transport belt 13 a in the transport belt 13. Thus, the inclination of the thread-like elastic body 7 is gradually changed during the conveyance in the y-direction, and the inclination of the thread-like elastic body 7 is orthogonal to the y-direction before being conveyed between the pair of belt-like sheets 50 and 60 ( x direction).

  As shown in FIG. 2, the belt-like sheet 50 is previously folded at both ends in the x direction on the outer surface side by a sailor (not shown) or the like, and the conveyor belt 12 (upper conveyor belt 12a, lower conveyor belt 12b). ) And the conveyor belt 13 (upper conveyor belt 13a, lower conveyor belt 13b) from the upper side of the nip rollers 171 and 172. In addition, as shown in FIG. 2, the belt-like sheet 60 is previously folded at both ends in the x-direction by a sailor (not shown) or the like, and is conveyed to the conveyor belt 12 (upper conveyor belt 12a, lower conveyor). The belt 12b) and the conveyor belt 13 (upper conveyor belt 13a, lower conveyor belt 13b) are supplied between a pair of nip rollers 171 and 172 from the lower side. In addition, before the strip | belt-shaped sheet 50 and / or the strip | belt-shaped sheet 60 are supplied between a pair of nip rollers 171,172, the adhesive agent is apply | coated to the inner surface side. The adhesive may be applied in a stripe shape, a spiral shape, a sine wave shape, or the like, or may be sprayed on the entire surface or applied in a solid shape.

  Next, the thread-like elastic body 7 is fixed in an extended state between the pair of belt-like sheets 50 and 60 using the nip rollers 171 and 172 (integration step). More specifically, a continuous body in which the continuously wound thread-like elastic body 7 is disposed between the pair of belt-like sheets 50 and 60 is supplied between the pair of nip rollers 171 and 172, and the pair of belt-like sheets 50. , 60 is fixed in a stretched state.

  As described above, with respect to the thread-like elastic body 7 fixed between the pair of belt-like sheets 50 and 60, as shown in FIG. 4 (b), the thread form in the region D introduced into the rotary arm 14 at the introduction speed V2. The elastic body 7 has less introduction amount of the elastic body than the thread-like elastic bodies 7 in the regions E and F introduced into the rotary arm 14 at the introduction speed V1, and the thread-like elastic body 7 disposed in the region D is elongated. The magnification is higher than the expansion magnification of the thread-like elastic body 7 disposed in each of the region E and the region F. That is, the contraction force of the thread-like elastic body 7 disposed in the region D is stronger than the contraction force of the thread-like elastic body 7 disposed in each of the region E and the region F. The plan view of the waist panel 3 shown in FIG. 1 is a schematic diagram, and the number of the thread-like elastic bodies 7 arranged in each region E, D, F of the waist panel 3 shown in FIG. The number of bar graphs (number of thread-like elastic bodies 7) in each of the regions E, D, and F shown in FIG. 1 does not match in the drawing, but actually, the region E of the waist panel 3 shown in FIG. Two thread-like elastic bodies 7 having the same number as the bar graph of the region E shown in FIG. 4B are arranged, and the region D of the waist panel 3 shown in FIG. 1 has the bar graph of the region D shown in FIG. Seven thread-like elastic bodies 7 equal to the number are arranged, and in the area F of the waist panel 3 shown in FIG. 1, five thread-like elastic bodies 7 that are the same as the number of bar graphs in the area F shown in FIG. It is arranged.

  Next, the thread-like elastic body 7 extending from both ends in the width direction (x direction) of the pair of belt-like sheets 50 and 60 is cut by the cutter 180 described above (cutting step).

  Next, both ends in the x direction of each of the belt-like sheets 50 and 60 folded to the outer surface side are folded outwardly in the width direction by a sailor (not shown) or the like, and the widened portions are bonded to each other. It joins by well-known joining means, such as an agent and a melt | fusion. Thereby, the band-shaped elastic sheet which fixed the thread-like elastic body 7 in the direction which cross | intersected the y direction between a pair of band-shaped sheets 50 and 60 can be manufactured continuously. The manufactured belt-like stretchable sheet is formed in the order of the region E, the region D, and the region F, and is a belt-like stretchable sheet in which the expansion ratio of the thread-like elastic body 7 is partially different. This belt-like stretchable sheet is intermittently cut in the x direction by a known cutting means (not shown). The interval of intermittently cutting is the same as the size of the waist panel 3 provided in the diaper 1. Thereby, the waist panel 3 (elastic sheet) which has the area | region E, the area | region D, and the area | region F as shown in FIG. 1 can be manufactured continuously.

  The stretchable sheet produced by the method for producing a stretchable sheet according to the present invention has the expansion ratio (extension ratio of the filamentous elastic body 7 arranged in the region E and the region F) of the most threadlike elastic body as the reference elongation ratio. In this case, the filamentous elastic body (disposed in the region D) having an expansion ratio different from the reference expansion ratio in the entire filamentous elastic body (the filamentous elastic body 7 disposed in the region D, the region E, and the region F) constituting the stretchable sheet. The ratio of the thread-like elastic body 7) is such that, when attached to the diaper 1, the tightening force of the part corresponding to the region D is weakened and the tightening force of the part corresponding to the region D is weakened. From the viewpoint of improving the fit when 1 is mounted, it is preferably 10 to 50%. Furthermore, it is more preferable that it is 30 to 50% from the viewpoint of preventing the filamentous elastic body 7 from being cut by a sudden change in the expansion ratio and stabilizing the production.

As a manufacturing method of the diaper 1 provided with the waist panel 3, a conveyance direction (y direction) is performed between a continuous body of the top sheet 21, a continuous body of the back sheet 22, and a continuous body of both sheets 21, 22 by a known method. Are provided with a plurality of elastic members 25 and a three-dimensional guard forming sheet which are intermittently provided with a plurality of absorbers 23, 23... And extended on both sides in the conveying direction (y direction) of the continuous body of the topsheet 21. A continuous body of the absorbent main body 2 in which 24 continuous bodies are arranged is manufactured in a separate process.
A pair of waist panels 3 are included in the continuous body of the absorbent main body 2 so as to protrude outward in the x direction while transporting the manufactured continuous body of the absorbent main body 2 in the transport direction (y direction). The continuous body of the diaper 1 distribute | arranged for every absorber 33 to be manufactured is manufactured. Here, the conveyance direction (y direction) of the continuous body of the absorbent main body 2 and the conveyance direction (y direction) when manufacturing the waist panel 3 (elastic sheet) are the same direction, and the waist panel 3 (extension and contraction). It is not necessary to invert the adhesive sheet) by 90 °. Then, the diaper 1 can be manufactured by cutting the continuous body into dimensions of individual diapers 1 by a known cutting means (not shown).

  The manufacturing method of the elastic sheet of this invention is not restrict | limited to the above-mentioned embodiment at all, and can be changed suitably.

  For example, in the manufacturing apparatus 11, the introduction speed of the filamentous elastic body 7 is controlled by the feed roller 156 of the speed adjusting unit 15B arranged on the upstream side of the rotary arm 14, but the speed adjusting unit 15B includes a feed roller 156. Instead of the roller 156, for example, a pair of nip rolls that can be brought into contact with or separated from each other by a force such as air pressure can be used above and below the thread-like elastic body 7. The case where a pair of the nip rolls are used will be described in detail. In a portion corresponding to the regions E and F, the pair of nip rolls are separated from each other, and the thread-like elastic body 7 is introduced into the inlet of the rotary arm 14 only by the tension adjusting means 15A. In the portion corresponding to the region D, the thread-like elastic body 7 tension-controlled by the tension adjusting means 15A is sandwiched between the pair of nip rolls, and the rotational speed of the nip rolls is adjusted. It is supplied to the inlet 145 of the rotary arm 14 at the introduction speed V2.

The elastic body winding means includes a disk having a thread-like elastic body introducing portion at the rotating shaft portion and an arm protruding downstream from the disk in the y direction. It is also possible to use one that wraps around the belt and winds the elastic thread around the conveyor belts 12 and 13.
Further, instead of fixing a thread-like elastic body between the pair of nip rolls 170, 171 by introducing a band-like sheet having a narrow width by folding back both ends in the width direction to the respective outer surface sides. Between the nip rolls 170 and 171, a belt-like sheet whose both ends in the width direction are not folded back may be introduced, and the thread-like elastic body may be fixed between the belt-like sheets.

  Further, as the conveyor belt, a conveyor belt as disclosed in WO 2005/060910 may be used instead of a pair of conveyor belts. In this case, only one conveyor belt may be used. Moreover, you may use the thread | yarn support member provided with the screw groove as described in FIGS. 4-6 of Unexamined-Japanese-Patent No. 2002-192641 as a longitudinal structure for thread | yarn conveyance.

Further, the inclination of the thread-like elastic body 7 is corrected in the direction orthogonal to the y-direction (x-direction), but is fixed to the pair of belt-like sheets 50 and 60 without being corrected at the angle wound around the conveyor belt 12. May be.
Moreover, in FIG. 1, although a pair of waist panels 3 and 3 were made into the rectangular shape, it is good also as a trapezoid or a parallelogram. When the pair of waist panels 3 and 3 are cut and formed from the stretchable sheet, it is preferable to have a shape having as few portions as possible to be discarded.

  According to the elastic sheet manufacturing method of the above embodiment, in order to manufacture the waist panel 3 having the region E, the region D, and the region F, the expansion magnification of the thread-like elastic body 7 disposed in the region E and the region F and The elongation magnification of the thread-like elastic body 7 arranged in the region D is divided into two kinds of extension magnifications, but the extension magnification of the thread-like elastic body 7 can be divided into a plurality of locations according to the target manufacturing object. it can.

  In addition to the waist panel 3 of the disposable diaper 1, the stretchable sheet produced by the production method of the present invention can be used for a waist part of a pant-type diaper, a cleaning sheet, a bandage, and the like.

DESCRIPTION OF SYMBOLS 1 Unfoldable disposable diaper 2 Absorbent main body 21 Top sheet 22 Back sheet 23 Absorber 24 Three-dimensional guard forming sheet 25, 26 Elastic member 3 Waist panel 3A Elastic sheet used for waist panel 4 Panel materials 5, 6 Sheet 50, 60 Band-shaped sheet 7 Thread-like elastic body 70 Bobbin 8 Fastening tape 11 Manufacturing device 12 Conveying belt (part of the longitudinal structure for yarn conveyance)
12a Upper conveyor belt 121, 122 Pulley 123 Roller 112a, 112b Roller 114 Belt 114a, 114b Roller 12b Lower conveyor belt 124, 125 Pulley 126 Roller 122a, 122b Roller 115 Belt 115a, 115b Roller 13 Conveyor belt (long structure for yarn conveyance) Part of
13a Upper transport belt 131, 132 Pulley 133 Roller 13b Lower transport belt 134, 135 Pulley 136 Roller 14 Rotating arm 141, 142, 143 Guide 15 Supply means 15A Tension adjustment means 151 Tensor 152 Feeding roller 153 Tension measuring instrument 15B Speed adjustment means 156 Feed roller 17 Integral means 171, 172 Nip rollers 173, 174 Straightening plate 175 Groove 176 Cutter blade 178 Groove 179 Extension part 18 Cutting means 180 Cutter A Abdominal side, B Back side, C Inseam

Claims (3)

A method for producing a stretchable sheet for continuously producing a stretchable sheet fixed in a state in which a thread-like elastic body is stretched in a direction intersecting the transport direction of the beltlike sheet between a pair of beltlike sheets,
A feeding step of continuously feeding out the thread-like elastic body and introducing the fed-out thread-like elastic body into an elastic body winding means; and a longitudinal structure for transferring the thread-like elastic body using the elastic body winding means. Integration that continuously winds around the body, transports the wound thread-like elastic body in the longitudinal direction of the longitudinal structure for thread transportation, and fixes the transported thread-like elastic body between sheets A process,
In the supplying step, the elastic sheet is manufactured by controlling the introduction speed of the thread-like elastic body to be introduced into the elastic body winding means, and manufacturing a stretchable sheet having partially different elongation ratios of the thread-like elastic body. Method.   2. The method for producing a stretchable sheet according to claim 1, wherein, in the supplying step, the introduction speed of the thread-like elastic body is controlled by speed adjusting means arranged on the upstream side of the elastic body winding means.   In the elastic sheet to be produced, when the elongation ratio of the most thread-like elastic body is the reference elongation ratio, the filament-like elasticity having an elongation ratio different from the reference elongation ratio of all the filamentous elastic bodies constituting the elastic sheet. The method for producing a stretchable sheet according to claim 1 or 2, wherein the proportion of the body is 10 to 50%.

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