JP7684896B2 - Manufacturing method of elastic laminate - Google Patents

Description

The present invention relates to a method for producing an elastic laminate that forms a ring-shaped structure that is stretchable in the circumferential direction and can be used as a component of various articles that require elasticity.

A separate type of pants-type absorbent article is known, which is equipped with an absorbent pad section including an absorbent core that absorbs and retains bodily fluids, and an annular holder section (waistband) that is placed around the wearer's waist and holds the absorbent pad section against the wearer's crotch, and is configured so that the absorbent pad section can be attached and detached from the holder section. The holder section is typically mainly made of an elastic laminate in which multiple sheets are laminated, such as an elastic sheet that is elastic in the circumferential direction and a fastening sheet for the holder section (e.g., a female member of a mechanical hook-and-loop fastener).

Patent Document 1 describes a method for manufacturing separate-type pants-type disposable diapers, which includes the steps of transporting a continuous body of the front body of the holder section and a continuous body of the back body in parallel with each other at a predetermined interval, arranging the absorbent pad section so as to straddle both continuous bodies being transported, folding the absorbent pad section in half in a direction perpendicular to the transport direction (direction perpendicular to the transport direction) to overlap both continuous bodies, cutting both overlapping strips to a predetermined length at predetermined locations in the transport direction, and joining both ends formed by the cut to form the holder section. Patent Document 2 describes a method for forming the holder section by folding a strip-shaped sheet member that is long in one direction in half.

Patent Documents 2 and 3 describe techniques for improving the side seals of typical non-separate pants-type disposable diapers. Patent Document 2 describes a technique for achieving both good appearance and softness in the side seals by bonding the left and right sides of the front and back panels together in a main bonding region, and forming a secondary bonding region with a weaker bonding strength than the main bonding region on the left and right outer sides of the main bonding region. Patent Document 3 describes a technique for improving the softness of the side seals by using ultrasonic waves to bond the side seals and not forming an area where adhesive is applied over the entire side seals.

JP 2003-175066 A JP 2014-233466 A JP 2013-146549 A

A typical non-separate pants-type disposable diaper comprises an absorbent body including a top sheet, a back sheet, and an absorbent body interposed between the two sheets, and an outer body which is an elastic laminate arranged on the non-skin-facing side of the absorbent body and which is an integrated front body and rear body. In the manufacturing process of such diapers, a continuous outer body structure in which a plurality of such outer bodies are connected in one direction in an unfolded state is conveyed in the same direction, while the absorbent body is placed on the continuous outer body structure, and then the continuous outer body structure is folded in half together with the absorbent body in the direction perpendicular to the conveyance direction, and the front body side and the rear body side of the continuous outer body structure are overlapped. In this case, the folding of the continuous outer body structure in two is easy because the relatively rigid absorbent body serves as the folding starting point, and the creases formed tend to be clear and neat. In contrast, the holder section, which is an elastic laminate, does not have an absorbent body, so if you try to manufacture it in the same way as the outer body by folding a continuous elastic sheet in half, with the front and back sections integrated, you will have problems with folding the continuous sheet because it has no fold points, and even if you can fold it, you will not be able to get a clean crease.

Therefore, as a method for producing an elastic laminate that does not have an object that serves as a folding starting point, such as the holder portion, instead of folding a continuous sheet including an elastic sheet in half in the direction perpendicular to the conveyance direction to produce an elastic laminate, a method is considered in which the continuous sheet is divided into two in the direction perpendicular to the conveyance direction by cutting the continuous sheet along a planned cutting line extending in the conveyance direction, and the two divided continuous sheets resulting from the division are overlapped to produce a continuous laminate. However, as a result of various studies by the present inventors on a production method including a step of dividing a continuous sheet into two in the direction perpendicular to the conveyance direction, when the cut edge portion of the continuous laminate corresponding to the planned cutting line (the overlapping portion of the cut edge portions corresponding to the planned cutting lines of each of the two divided continuous sheets) includes a convex portion that is convex toward the outside in the direction perpendicular to the conveyance direction in a plan view, problems such as the convex portion turning up or the convex portion becoming wrinkled occur during the conveyance of the continuous laminate to the next process. In this way, if the transport of the continuous laminate, which is an intermediate product in the manufacturing process of the elastic laminate, is unstable and curling or wrinkling occurs on the edges of the continuous laminate along the transport direction during transport, there is a risk that the appearance and functionality of the elastic laminate will be reduced.

The objective of the present invention is to provide a technology that has excellent transport stability for intermediate products and can stably produce elastic laminates.

The present invention is a method for producing an elastic laminate comprising a first elastic sheet having elasticity in one direction, and a second elastic sheet overlaid on one side of the first elastic sheet and having elasticity in the one direction, wherein the two elastic sheets are joined to each other at a pair of joints formed at both ends in the one direction, and are not joined to each other in the portion sandwiched between the pair of joints, and the portion sandwiched between the pair of joints can form a ring-shaped structure having elasticity in the circumferential direction.
One embodiment of a manufacturing method for an elastic laminate of the present invention includes a dividing step of conveying an original sheet including a continuous band-like elastic sheet that is continuous in one direction and stretched in that one direction in a conveying direction, cutting the original sheet in half in a direction perpendicular to the conveying direction and along a planned cutting line that meanders about a center line extending parallel to the conveying direction, thereby dividing the original sheet into a first continuous sheet in which a plurality of first elastic sheets are connected in the conveying direction and a second continuous sheet in which a plurality of second elastic sheets are connected in the conveying direction.
One embodiment of the manufacturing method for an elastic laminate of the present invention includes a lamination step of overlapping the first continuous sheet and the second continuous sheet so that the cut edges of both continuous sheets at the intended cutting line coincide with each other to obtain a continuous laminate.
One embodiment of the manufacturing method for an elastic laminate of the present invention includes a temporary joining step of joining the two continuous sheets together to form a temporary joint, which forms a convex portion extending outward in the direction perpendicular to the conveying direction at the cut edge of the continuous laminate.
One embodiment of the method for producing a stretchable laminate of the present invention includes a joining step of intermittently forming the joints in the continuous laminate in the conveying direction.
One embodiment of the method for producing a stretchable laminate of the present invention includes a sheet-cutting step of cutting the continuous laminate in the direction perpendicular to the conveyance direction to obtain sheets of the stretchable laminate.
Other features, advantages and embodiments of the present invention are described below.

The manufacturing method for the elastic laminate of the present invention provides excellent transport stability for the intermediate product (continuous laminate), making it possible to stably manufacture high-quality elastic laminates.

FIG. 1 is a schematic plan view of one embodiment of a stretchable laminate (a holder portion of a pants-type disposable diaper) produced by the production method of the present invention. FIG. 2 is a cross-sectional view that shows a schematic cross-section taken along line II in FIG. 1 (a cross-section along the width direction and thickness direction of the elastic laminate shown in FIG. 1). FIG. 3 is a schematic perspective view of one embodiment of a pants-type disposable diaper using the elastic laminate shown in FIG. FIG. 4 is a partially cutaway schematic plan view of the skin-facing side of the diaper shown in FIG. 3 in an unfolded and stretched state. FIG. 5 is a partially cutaway perspective view showing a schematic example of a stretch sheet (outer layer sheet) according to the present invention. FIG. 6 is a schematic perspective view of a manufacturing apparatus used to manufacture the elastic laminate shown in FIG. FIG. 7 is a cross-sectional view showing a schematic cross section taken along line II-II in FIG. 6 (a cross section along the direction perpendicular to the conveyance direction and the thickness direction of the raw sheet precursor). FIG. 8 is a cross-sectional view that typically shows a cross section along a direction perpendicular to the conveyance direction and in a thickness direction of the original sheet manufactured by the manufacturing apparatus shown in FIG. FIG. 9 is a schematic diagram of a production line (second production section) for the elastic laminate in the production apparatus shown in FIG. FIG. 10 is a diagram showing an overview of an example of a series of steps from dividing an original sheet to obtaining a continuous laminate in the manufacturing method of the present invention, in which FIG. 10(a) is a schematic plan view of an original sheet before the dividing step in the manufacturing apparatus shown in FIG. 6, FIG. 10(b) is a schematic plan view of two continuous sheets obtained by the dividing step, FIG. 10(c) is a schematic plan view showing the phase alignment of the two continuous sheets in the conveying direction, and FIG. 10(d) is a schematic plan view of a continuous laminate obtained by overlapping the two continuous sheets. FIG. 11(a) is a schematic plan view of the continuous laminate after the temporary bonding process in the manufacturing apparatus shown in FIG. 6, and FIG. 11(b) is a schematic plan view of the continuous laminate after the bonding process carried out after the temporary bonding process. 12(a) to 12(c) are diagrams showing an overview of an example of the sheet-slicing process in the manufacturing method of the present invention, and are enlarged plan views showing a schematic view of a portion cut in the sheet-slicing process. FIG. 13 is an enlarged schematic plan view of one end in the longitudinal direction of the elastic laminate shown in FIG.

The present invention will now be described based on preferred embodiments thereof with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. The drawings are essentially schematic, and the ratios of the dimensions may differ from the actual ones.

1 and 2 show an elastic laminate 1, which is one embodiment of an elastic laminate manufactured by the manufacturing method of the present invention. The elastic laminate 1 comprises a first elastic sheet 1A having elasticity in one direction, specifically the longitudinal direction of the elastic laminate 1 indicated by the symbol Y in the figure, and a second elastic sheet 1B overlapped on one side of the sheet 1A and having elasticity in the direction Y. The two sheets 1A and 1B are joined to each other at a pair of joints 9, 9 formed at both ends in the direction Y, and are not joined to each other in the portion sandwiched between the pair of joints 9, 9, and the portion sandwiched between the pair of joints 9, 9 can form a ring-shaped structure having elasticity in the circumferential direction.

As shown in Figures 3 and 4, the elastic laminate 1 is used as a holder section 17 which is a component of a pants-type disposable diaper 10, which is a type of pants-type absorbent article. As shown in Figure 4, the diaper 10 has a vertical direction (direction X) extending from the wearer's abdomen side through the crotch area to the back side, and a horizontal direction (direction Y) perpendicular to the vertical direction, and is equipped with an absorbent pad section 11 including an absorbent core 14 which absorbs and retains bodily fluids, and an annular holder section 17 (elastic laminate 1) which is disposed around the wearer's waist and holds the absorbent pad section 11 against the wearer's crotch area.
Direction X is the width direction (short direction) of the elastic laminate 1 (sheets 1A, 1B) and also the vertical direction of the diaper 10, and direction Y is the longitudinal direction of the elastic laminate 1 (sheets 1A, 1B) and also the horizontal direction of the diaper 10.

The absorbent pad section 11 is configured to be detachable from the holder section 17. That is, the absorbent pad section 11 and the holder section 17 are separate members before the diaper 1 is used. When the diaper 1 is used, the fastening tape 16 of the absorbent pad section 11 is fastened to the target tape 7 of the holder section 17 to join the two together, forming a pants-type diaper having a pair of joints 9, 9, a waist opening WH, and a pair of leg openings LH, LH, as shown in FIG. 3. The joints 9 of the holder section 17 correspond to the side seals of a typical non-separate pants-type disposable diaper. In this embodiment, the joints 9 are linear and extend along the X direction, and extend over the entire length of the elastic laminate 1 in the X direction.

As shown in Figures 3 and 4, the absorbent pad section 11 includes a liquid-permeable top sheet 12 arranged relatively close to the wearer's skin, a liquid-impermeable, poorly liquid-permeable or water-repellent back sheet 13 arranged relatively far from the wearer's skin, and an absorbent core 14 arranged between the two sheets 12, 13. These members constituting the absorbent pad section 11 are integrated with each other by a known joining means such as an adhesive. The absorbent pad section 11 has a rectangular shape in a plan view, and when the diaper 10 is worn, its longitudinal direction coincides with the direction X as shown in Figure 4. A pair of leak-proof cuffs 15, 15 are arranged on both sides of the absorbent pad section 11 along the direction X, which stand up against the wearer's skin when the diaper 10 is worn. Each leak-proof cuff 15 includes a leak-proof cuff forming sheet 150 that forms the main body of the leak-proof cuff 15, and an elastic member 151 fixed to the sheet 150 in a stretched state in the direction X. The inner surface (skin-facing surface) of each of the two ends of the absorbent pad portion 11 in the X direction is provided with a fastening tape 16 (see Figure 4) for attaching the absorbent pad portion 11 to the holder portion 17.

The elastic laminate 1 constituting the holder section 17 is mainly composed of a laminate of a first elastic sheet 1A and a second elastic sheet 1B. Both sheets 1A, 1B have the same shape and dimensions in a plan view as shown in FIG. 1, and in the elastic laminate 1, both sheets 1A, 1B are overlapped with their respective contours aligned. The elastic laminate 1 is formed symmetrically with respect to a horizontal centerline (not shown) that bisects the elastic laminate 1 in direction Y and extends in direction X.

As shown in Figures 1 and 4, the elastic laminate 1 (sheets 1A and 1B) has a pair of longitudinal ends X1 and X2 extending in the direction Y. The longitudinal end X1, which is the upper end when the holder part 17 is worn, is a straight line parallel to the direction Y in a plan view, whereas the longitudinal end X2, which is the lower end when the holder part 17 is worn, forms a convex portion that is almost entirely convex toward the longitudinal end X1 (toward the inside of the direction X) in a plan view.

The first elastic sheet 1A and the second elastic sheet 1B each include an outer body 2 that forms the outer surface (non-skin-facing surface) of the elastic laminate 1, and a reinforcing sheet 5 that forms the inner surface (skin-facing surface) of the elastic laminate 1.
In this specification, the "skin-facing surface" refers to the surface of the absorbent article or its constituent parts (absorbent pad portion, holder portion, etc.) that faces the wearer's skin when the absorbent article is worn, and the "non-skin-facing surface" refers to the surface of the absorbent article or its constituent parts that faces the side opposite the skin when the absorbent article is worn.
2, in this embodiment, the exterior body 2 includes an outer layer sheet 3 that forms the outer surface of the elastic laminate 1, and an inner layer sheet 4 that is superimposed on the inner surface of the sheet 3, and is mainly a laminate of both sheets 3, 4. Both sheets 3, 4 are joined together and integrated by a joining means such as an adhesive or fusion.
As shown in Fig. 2, the exterior body 2 (sheets 3 and 4) is folded back on the longitudinal end X1 side of the elastic laminate 1 toward the inner side, so that a folded-back portion 20 extending from the longitudinal end X1 along the direction X is formed on the inner surface (skin-facing surface) of both sheets 1A and 1B. The folded-back portion 20 and the exterior body 2 facing it are joined to each other by a joining means such as an adhesive or fusion. As shown in Fig. 2, the reinforcing sheet 5 is disposed at a position spaced a predetermined distance in the direction X from the folded-back portion 20 of the exterior body 2. The length of the reinforcing sheet 5 in the direction Y is the same as that of the exterior body 2 (sheets 3 and 4), but the length of the reinforcing sheet 5 in the direction X is shorter than that of the exterior body 2 (sheets 3 and 4). The vertical end 5a of the reinforcing sheet 5 on the folded-back portion 20 side (the upper end when the holder portion 17 is worn) is straight and parallel to the direction Y in a planar view, and the vertical end 5b of the reinforcing sheet 5 on the opposite side to the folded-back portion 20 side (the lower end when the holder portion 17 is worn) together with the outer casing 2 constitutes the vertical end X2 of the elastic laminate 1, and has a convex portion that is convex toward the vertical end X1 in a planar view.
Nonwoven fabrics manufactured by various methods, resin films, and the like can be used for the outer layer sheet 3, inner layer sheet 4, and reinforcing sheet 5 that constitute the exterior body 2. Specific examples of nonwoven fabrics that can be used for the sheets 3, 4, and 5 include spunbond nonwoven fabrics, air-through nonwoven fabrics, and needle-punched nonwoven fabrics, and they may have a single-layer structure or a laminate structure in which one or more types of nonwoven fabrics are laminated.

The outer layer sheet 3 is a stretchable sheet stretched in one direction, specifically in the longitudinal direction of the stretchable laminate 1 or in the transverse direction of the diaper 10, in the Y direction, and has stretchability in the Y direction. The stretchable sheet is obtained by stretching an unstretched sheet such as a nonwoven fabric. The stretching process is typically carried out by using a processing means equipped with a pair of grooved rolls on the periphery of which the interlocking grooves are provided along the direction of the rotation axis, and by rotating the rolls to supply the unstretched sheet to the interlocking portions. By such stretching process, the unstretched sheet is formed with high basis weight portions having a relatively high basis weight and low basis weight portions having a relatively low basis weight alternately in the feeding direction (MD), and the unstretched sheet becomes a stretched sheet having stretchability in the MD. The stretchable sheet can be produced, for example, according to the method described in JP 2009-61743 A.

Figure 5 shows a stretch sheet 3A, which is a preferred example of the outer layer sheet 3. The stretch sheet 3A has two opposing fiber sheets 31, 32 and a plurality of elastic filaments 33 arranged between the two fiber sheets 31, 32 and extending in one direction (direction Y) without crossing each other. The plurality of elastic filaments 33 are joined to the stretchable fiber sheets 31, 32 in a substantially unstretched state over their entire longitudinal length.

Both fiber sheets 31, 32 are stretchable in the direction (direction Y) in which elastic filaments 33 extend. Here, "stretchable" includes (1) the case where the constituent fibers of fiber sheets 31, 32 themselves stretch, and (2) the case where the constituent fibers themselves do not stretch, but the fiber sheets 31, 32 as a whole stretch because fibers bonded at intersections become separated, the three-dimensional structure formed by multiple fibers due to bonding between fibers, etc., changes structurally, or constituent fibers break.

The fiber sheets 31, 32 may each be a nonwoven fabric made of short fibers. Examples of nonwoven fabric include air-through nonwoven fabric, heat-rolled nonwoven fabric, spunlace nonwoven fabric, spunbond nonwoven fabric, and meltblown nonwoven fabric. The sheets 31, 32 may be the same or different. Here, "the same" means that the manufacturing process, the type of constituent fibers, the fiber diameter and length of the constituent fibers, and the thickness and basis weight of the fiber sheet are all the same for the two contrasting fiber sheets. If even one of these is different, the contrasting fiber sheets are "different" from each other.

The elastic filament 33 is made of, for example, a thermoplastic elastomer or rubber. In particular, when a thermoplastic elastomer is used as a raw material, it can be melt-spun using an extruder in the same way as a normal thermoplastic resin, and the elastic filament obtained in this way is easy to heat-seal, making it suitable for the stretch sheet 3A. That is, an example of a preferred elastic filament 33 is an elastic filament formed by stretching an elastic resin in a molten or softened state. The bonding between such a preferred elastic filament 33 and the fiber sheets 31, 32 is achieved by fusing the constituent fibers (non-elastic fibers) of both sheets 31, 32 to the elastic filament 33 in a state where they are embedded in the elastic filament 33, and is not achieved by using an adhesive such as a hot-melt adhesive. Therefore, there is no adhesive between the fiber sheets 31, 32 and the elastic filament 33 bonded thereto.

The inner layer sheet 4 and the reinforcing sheet 5 may each be a stretchable sheet that has stretchability in the Y direction, or a non-stretchable sheet that has no stretchability. Typically, both sheets 4 and 5 are non-stretchable sheets.

In this embodiment, the first elastic sheet 1A and the second elastic sheet 1B each further include a functional sheet 6 in addition to the reinforcing sheet 5 as a sheet forming the inner surface (skin-facing surface) of the elastic laminate 1. In the present invention, the functional sheet 6 is intended to impart various functions to the holder portion 17, and in this embodiment, the functional sheet 6 is intended to absorb and retain sweat of the wearer, and is disposed so as to come into contact with the skin of the wearer.
In this embodiment, as shown in Fig. 2, the functional sheet 6 is disposed so as to straddle the folded-back portion 20 of the exterior body 2 and the reinforcing sheet 5 in the direction X, and as shown in Fig. 4, the functional sheet 6 has a shape that is long in one direction (specifically, a rectangular shape) in a plan view, and extends continuously over the entire length of both sheets 1A, 1B in the direction Y with its longitudinal direction coinciding with the direction Y. The length of the functional sheet 6 in the direction X is shorter than that of both sheets 1A, 1B.
The functional sheet 6 having a sweat absorbing function is not particularly limited as long as it is a sheet capable of absorbing sweat, but typically, nonwoven fabrics produced by various manufacturing methods are used. Specific examples of nonwoven fabrics that can be used as the functional sheet 6 having a sweat absorbing function include air-through nonwoven fabrics, spunbond nonwoven fabrics, spunlace nonwoven fabrics, airlaid nonwoven fabrics, meltblown nonwoven fabrics, and needle punch nonwoven fabrics, and may also be composite nonwoven fabrics in which two or more types of nonwoven fabrics are laminated.

In this embodiment, the first elastic sheet 1A and the second elastic sheet 1B each include a target tape 7 disposed on the outer surface (non-skin facing surface) of the outer layer sheet 3. The target tape 7 is a fastening destination for the fastening tape 16 (see FIG. 4 ) provided on the absorbent pad section 11, and the reason why the absorbent pad section 11 is configured to be freely attachable to and detachable from the holder section 17 is due to the fastening tape 16 provided on the absorbent pad section 11 and the target tape 7 provided on the elastic laminate 1 as the holder section 17.
1, the target tape 7 has a shape that is long in one direction (specifically, a rectangular shape) in a plan view, and extends continuously over the entire length of each of the sheets 1A, 1B in the direction Y with its longitudinal direction coinciding with the direction Y. Furthermore, the length of the target tape 7 in the direction X is shorter than that of both sheets 1A, 1B, and the center of the target tape 7 in the direction X is positioned closer to the longitudinal end X2 than the centers of both sheets 1A, 1B in the direction X.

In the present invention, the configurations of the fastening tape 16 and the target tape 7 are not particularly limited, provided that the absorbent pad portion 11 is detachable from the holder portion 17. For example, the fastening tape 16 may be configured to have an adhesive portion formed by applying an adhesive or the like to a tape base material, and the fastening tape 16 may be adhered to the target tape 7 via the adhesive portion.
In this embodiment, mechanical hook-and-loop fasteners are used as the fastening tape 16 and the target tape 7. The term "mechanical hook-and-loop fastener" used here refers to a fastener that is a set of a surface member with hook-shaped protrusions on one surface and a surface member with pile-shaped protrusions on one surface. A specific example of a mechanical hook-and-loop fastener is Magic Tape (registered trademark). The fastening tape 16 includes a male member of a mechanical hook-and-loop fastener, and typically includes a tape substrate made of a resin film, woven fabric, nonwoven fabric, or the like, on the surface of which a number of protruding engagement members are arranged. The target tape 7 includes a female member of a mechanical hook-and-loop fastener, and typically includes a number of loop members arranged on the surface of the substrate sheet.

In this embodiment, as shown in FIG. 2, a plurality of elastic members 8 are arranged between the exterior body 2 (inner layer sheet 4) and the reinforcing sheet 5, and between the folded portion 20 and the exterior body 2 facing it, so as to be stretchable in the direction Y. As shown in FIG. 4, the plurality of elastic members 8 extend over the entire length of both sheets 1A and 1B in the direction Y, and are arranged intermittently in the direction X. Each elastic member 8 is fixed to the sheets 4 and 5 that contact the elastic member 8 by adhesive. When the holder portion 17 is worn, the contraction of the elastic members 8 forms a plurality of folds (gathers) on the surfaces of both sheets 1A and 1B that extend in a direction intersecting the elastic members 8 (direction X). The number and arrangement of the elastic members 8 are not particularly limited, and can be set appropriately in consideration of the fit of the holder portion 17 to the wearer's body, etc.

Next, the manufacturing method of the elastic laminate of the present invention will be described with reference to the drawings, taking as an example the manufacturing method of the elastic laminate 1 (holder portion 17) described above. Figure 6 shows a manufacturing apparatus 70 used to implement the manufacturing method of the elastic laminate 1. The manufacturing apparatus 70 includes a first manufacturing section 71 which carries out the manufacturing process of the raw fabric sheet 90, and a second manufacturing section 72 which manufactures the elastic laminate 1 (holder portion 17) using the continuous belt-like raw fabric sheet 90 manufactured in the first manufacturing section 71. In the second manufacturing section 72, the following steps are carried out: cutting the original sheet 90 along a planned cutting line CL (see FIG. 10(a)) extending in the conveying direction MD to divide the original sheet 90 into a first continuous sheet 91 and a second continuous sheet 92 (division step); overlapping the two sheets 91, 92 to obtain a continuous laminate 93 (lamination step); temporarily joining the two sheets 91, 92 together at a predetermined portion of the continuous laminate 93 (temporary joining step); forming the joint 9 in the continuous laminate 93 (joining step); and cutting the continuous laminate 93 in the conveying orthogonal direction CD to obtain individual sheets of the elastic laminate 1 (single sheet process).

The method for producing the elastic laminate 1 of this embodiment includes, prior to the dividing step, a process for producing a raw sheet 90 which is divided into two in the cross conveyance direction CD in the dividing step. The process for producing the raw sheet 90 will be described below.
The raw sheet 90 is a continuous strip-shaped sheet including a continuous strip-shaped stretch sheet stretched in one direction, and in this embodiment, a continuous strip-shaped outer layer sheet 3, more specifically, a continuous strip-shaped stretch sheet 3A (see Figure 5), is used as the stretch sheet.
The conveying direction MD coincides with the longitudinal direction (continuous direction) of the original sheet 90 (stretch sheet 3A), and the conveying orthogonal direction CD, which is perpendicular to the conveying direction MD, coincides with the width direction (short direction) of the original sheet 90 (stretch sheet 3A).

In the first manufacturing section 71, as shown in FIG. 6, a continuous strip of an inner layer sheet 4 (first raw material sheet) is arranged on one side (the upper side in the illustrated embodiment) of the stretch sheet 3A being transported in the transport direction MD so as to overlap with a planned cutting line CL (see FIG. 10(a)) described later, and a pair of continuous strip of target tapes 7, 7 (second raw material sheet) are arranged on both sides of the planned cutting line CL on the other side (the lower side in the illustrated embodiment) of the stretch sheet 3A in the transport perpendicular direction CD, to obtain a continuous strip of raw sheet precursor 80, and further, the sheets 3A, 4, 7 constituting the raw sheet precursor 80 are joined together.
In this embodiment, the length (width) of the inner layer sheet 4 in the conveying direction CD is the same as or longer than that of the stretch sheet 3A. On the other hand, the length (width) of the target tape 7 in the conveying direction CD is shorter than that of the stretch sheet 3A.
The sheets 3A, 4, and 7 constituting the raw sheet precursor 80 are joined together by a joining means 73 provided in the first manufacturing section 71. A device conventionally used for joining sheets of this type can be used as the joining means 73. In this embodiment, the joining means 73 includes a melting means 730 such as an ultrasonic horn that heats and melts the workpieces (sheets 3A, 4, and 7), and a receiving roll 731, and is configured to be able to melt the workpieces supplied between the opposing peripheral surfaces of the melting means 730 and the receiving roll 731 while applying pressure to them.

In this embodiment, as shown in FIG. 6, after the sheets 3A, 4, and 7 constituting the raw sheet precursor 80 are joined together by the joining means 73, a plurality of elastic members 8 are arranged and fixed in a stretched state stretched to a predetermined stretch rate on the elastic member arrangement surface (the surface on the inner layer sheet 4 side in the illustrated embodiment) of the raw sheet precursor 80 being transported in the transport direction MD. Before the elastic members 8 are arranged on the elastic member arrangement surface and/or the elastic members 8, an adhesive such as a hot melt adhesive is applied by an adhesive applicator (not shown), and the elastic members 8 are arranged on the elastic member arrangement surface, whereby the elastic members 8 are joined and fixed to the raw sheet precursor 80.

In this embodiment, as shown in FIG. 6, in the manufacturing process of the raw sheet 90, both side edge portions 80S, 80S along the conveying direction MD of the raw sheet precursor 80 are folded back to one side of the raw sheet precursor 80 (to the inner layer sheet 4 side in the illustrated embodiment) to form a pair of folded back portions 20, 20 and a folded back portion non-existent portion 21 located between the pair of folded back portions 20, 20 (folding process). As described above, the folded back portion 20 forms one side edge portion of the elastic laminate 1 in the longitudinal direction Y (the lateral direction Y of the holder portion 17). By forming the one side edge portion by folding back the sheet in this way, the appearance of the elastic laminate 1 is improved, and the appearance of the holder portion 17 (diaper 10) can be further improved.

In the folding step, any of the sheets 3A, 4, and 7 constituting the raw sheet precursor 80 may be folded, but as shown in FIG. 7, it is preferable to fold the stretch sheet 3A and the inner layer sheet 4 (first raw material sheet) (without folding the target tape 7). The stretch sheet 3A is more likely to meander during transportation than the other sheets constituting the raw sheet precursor 80, and if the stretch sheet 3A meanders during the manufacturing process of the stretch laminate 1, this may lead to a deterioration in the appearance and functionality of the resulting stretch laminate 1. By folding the stretch sheet 3A and the inner layer sheet 4 in the folding step, such inconveniences can be effectively prevented.

In this embodiment, in the manufacturing process of the raw sheet 90, as shown in FIG. 6, a continuous belt-shaped reinforcing sheet 5 (third raw sheet) is arranged in the folded-back portion non-existing portion 21 on the inner layer sheet 4 (first raw sheet) side of the raw sheet precursor 80 so as to overlap with the planned cutting line CL. This increases the rigidity of the folded-back portion non-existing portion 21 in the raw sheet 90, so that the cut edge portions 91a, 92a (see FIG. 10(b)) of the first continuous sheet 91 and the second continuous sheet 92 obtained by cutting the raw sheet 90 along the planned cutting line CL in the dividing process are effectively prevented from being turned over during the subsequent transportation of both sheets 91, 92, and manufacturing efficiency can be further improved.

In this embodiment, in the manufacturing process of the raw sheet 90, as shown in FIG. 6 and FIG. 8, a pair of continuous belt-like functional sheets 6 (fourth raw sheet) are arranged on the surface of the raw sheet precursor 80 on the side of the inner layer sheet 4 (first raw sheet) so as to overlap the boundary 22 between the pair of folded portions 20, 20 and the reinforcing sheet 5 (third raw sheet). This results in a continuous belt-like raw sheet 90 in which the stretch sheet 3A and the first to fourth raw sheet sheets 4 to 7 are laminated. The boundary 22 between the folded portion 20 and the reinforcing sheet 5 is the gap between the folded portion 20 and the reinforcing sheet 5 as shown in FIG. 8, and is a portion in which the number of sheets stacked in the direction X of the stretch laminate 1 is relatively small. As described above, in this embodiment, the joint 9 (see FIG. 1) extends over the entire length of the stretch laminate 1 in the direction X, and overlaps with the boundary 22. If the joint 9 exists so as to straddle the portion in which the number of sheets stacked is different, there is a concern that the bonding strength of the joint 9 will vary. However, as mentioned above, by overlapping the reinforcing sheet 5 at the boundary 22 where the number of laminated sheets is relatively small, such concerns can be eliminated, and the bonding strength of the joint 9 can be made constant over its entire length in the longitudinal direction.

The continuous belt-like raw fabric sheet 90 produced in the first production section 71 in the above manner is then transported to the second production section 72 and used to produce the elastic laminate 1. Figure 9 shows a schematic configuration of the second production section 72, and Figure 10 shows the state of the raw fabric sheet 90 and other processed materials in each section of the second production section 72.

In the second manufacturing section 72, first, the original sheet 90 is transported with its continuous direction being the transport direction MD, and cut along a planned cutting line CL (see Figure 10 (a)) extending in the transport direction MD, thereby dividing the original sheet 90 into a first continuous sheet 91 and a second continuous sheet 92 (division process).
The dividing step is performed by a cutting means 74 provided in the second manufacturing section 72. A device conventionally used for cutting this type of sheet can be used as the cutting means 74. In this embodiment, the cutting means 74 includes a cutter roll 740 having a blade for cutting the sheet, and a receiving roll 741.

10A, the planned cutting line CL meanders about a center line 90L that bisects the original web sheet 90 in the cross-transport direction CD and extends parallel to the transport direction MD. In the illustrated embodiment, the planned cutting line CL meanders symmetrically with respect to the center line 90L, and therefore the first continuous sheet 91 and the second continuous sheet 92 are in a symmetrical relationship with respect to the planned cutting line CL. The planned cutting line CL is typically a virtual line and is not provided on the original web sheet 90 so as to be visible to the naked eye, but may be provided so as to be visible.
In this embodiment, the cutting line CL has a shape in which a convex portion convex on one side of the conveyance cross direction CD and a convex portion convex on the other side are alternately arranged in the conveyance direction MD in a plan view as shown in Fig. 10(a). The shape of the cutting line CL in a plan view is not particularly limited, provided that the cutting line CL meanders with respect to the center line 90L as a reference, and does not have to meander symmetrically with respect to the center line 90L as shown in Fig. 10(a). The shape of the cutting line CL in a plan view may be, for example, a shape in which the convex portion is trapezoidal in a plan view, such that the contour line is made up of only straight lines, or a shape in which the contour line is S-shaped, such that the contour line is made up of only curved lines, or a shape in which straight lines and curved lines are mixed.

The first continuous sheet 91 has a configuration in which the first stretchable sheet 1A is connected in one direction (the conveying direction MD), and the second continuous sheet 92 has a configuration in which the second stretchable sheet 1B is connected in one direction (the conveying direction MD). The first continuous sheet 91 has, as a pair of edges extending in the conveying direction MD, a non-linear cut edge portion 91a and a linear edge portion 91b caused by cutting the original sheet 90 at the planned cutting line CL. The second continuous sheet 92 has, as a pair of edges extending in the conveying direction MD, a non-linear cut edge portion 92a and a linear edge portion 92b caused by cutting the original sheet 90 at the planned cutting line CL. The non-linear cut edges 91a, 92a form the longitudinal end X2 of the elastic laminate 1 (the lower end of the holder section 17 when worn), and the linear edges 91b, 92b form the longitudinal end X1 of the elastic laminate 1 (the upper end of the holder section 17 when worn) (see Figure 1, etc.).

As shown in FIG. 9, the second manufacturing unit 72 has a conveying path 910 for the first continuous sheet 91 and a conveying path 920 for the second continuous sheet 92, and both conveying paths 910, 920 are independent of each other over a predetermined distance.

After the dividing step, the first continuous sheet 91 and the second continuous sheet 92 are overlapped so that the cut edges 91a, 92a of the two continuous sheets 91, 92 coincide with each other along the planned cutting line CL to obtain a continuous laminate 93 (lamination step).
In the present embodiment, in the lamination step, first, while conveying the first continuous sheet 91 and the second continuous sheet 92 in the conveying direction MD on the conveying paths 910 and 920, one or both of the sheets 91 and 92 are rotated about the conveying direction MD so that the cut edges 91a and 92a of the sheets 91 and 92 at the planned cutting lines CL face the same direction (rotation step). Then, after or during the rotation step, the first continuous sheet 91 and the second continuous sheet 92 are overlapped as shown in FIG. 10(d) with the phases of the cut edges 91a and 92a of the sheets 91 and 92 aligned in the conveying direction MD as shown in FIG. 10(c), to obtain a continuous laminate 93. The continuous laminate 93 has a pair of edges 93a, 93b extending in the machine direction MD (longitudinal direction), one of which, the non-linear cut edge 93a, is formed by an overlapping portion of the non-linear cut edges 91a, 92a of both sheets 91, 92, forming a non-linear longitudinal direction X2 of the elastic laminate 1, and the other, linear edge 93b, is formed by an overlapping portion of the linear edges 91b, 92b of both sheets 91, 92, forming a linear longitudinal direction X1 of the elastic laminate 1.

6, in this embodiment, one side of the conveyance orthogonal direction CD is the operation side (hereinafter also referred to as the "OP side") of a manufacturing apparatus 70 used to implement the manufacturing method for the elastic laminate 1, and the other side of the conveyance orthogonal direction CD is the drive side (hereinafter also referred to as the "DR side") of the manufacturing apparatus 70, with the first continuous sheet 91 located on the OP side and the second continuous sheet 92 located on the DR side. The OP side is the side where an operator who operates the manufacturing apparatus 70 is located, and the DR side is the side where many of the driving devices for operating each part of the manufacturing apparatus 70 are located.
As described above, in the rotating step, one or both of the sheets 91, 92 may be rotated around the conveyance direction MD so that the cut edge 91a of the first continuous sheet 91 and the cut edge 92a of the second continuous sheet 92 face in the same direction, and although the direction in which the cut edge 91a, 92a faces after the rotating step may be either the OP side or the DR side, the DR side is preferred as shown in Fig. 10(b) . This is because the rotation and movement of the sheets 91, 92 can be performed smoothly and accurately. That is, the rotation step and the stacking step, which is the next step, are typically performed by acquiring position information using a detection means (not shown) such as a sensor installed on the OP side, and rotating and moving both sheets 91 and 92 based on the position information, and since the linear edges 91b and 92b are more easily detected by the detection means than the nonlinear cut edges 91a and 92a, and the position information is more accurate and easier to handle, it is preferable that the linear edges 91b and 92b always face the OP side during the rotation step and the stacking step, in other words, it is preferable that the nonlinear cut edges 91a and 92a always face the DR side. Therefore, in the rotation step, it is preferable that the cut edges 91a and 92a of both sheets 91 and 92 face the DR side.

In this embodiment, in order to orient the cut edges 91a, 92a of both sheets 91, 92 to the DR side in the rotating step, the second continuous sheet 92, whose cut edge 92a faces the OP side immediately after the dividing step, is rotated 180 degrees around the conveying direction MD. On the other hand, the first continuous sheet 91, whose cut edge 91a faces the DR side immediately after the dividing step, is not rotated around the conveying direction MD.
9, the conveying path 920 of the second continuous sheet 92 is provided with a sheet rotation area 75 that rotates the second continuous sheet 92 180 degrees around the conveying direction MD during conveying, and the sheet rotation area 75 has a plurality of cylindrical conveying rolls 750 as sheet rotating means intermittently arranged in the conveying direction MD with their axial directions aligned with the conveying cross direction CD. The conveying rolls 750 in the sheet rotation area 75 are arranged such that the angles between their axial directions and the horizontal direction (vertical direction) are different from one another, and the angles increase or decrease from the upstream side to the downstream side of the conveying direction MD (from the left side to the right side in FIG. 9). The second continuous sheet 92 is conveyed in the conveying direction MD through the sheet rotation area 75 configured in this way, and is rotated 180 degrees around the conveying direction MD.
The number of transport rolls 750 arranged in the sheet rotation region 75 is not particularly limited, and can be appropriately adjusted depending on the rotation angle of the sheet, etc. The sheet rotating means is also not particularly limited, and any known rotating means capable of rotating the sheet around the transport direction during transport can be appropriately used.

In the plan view shown in FIG. 10, the cut edges 91a and 92a are wavy lines in which convex and concave portions are alternately arranged in the conveying direction MD. If the distance between the tops of two adjacent convex portions in the conveying direction MD is one pitch, the cut edges 91a and 92a are shifted by 0.5 pitches in the conveying direction MD immediately after the division process (before the phase alignment of the cut edges 91a and 92a in the conveying direction MD) (see FIG. 10(a) and FIG. 10(b)). In the stacking process, the phase offset in the conveying direction MD between the cut edges 91a and 92a is eliminated, and the sheets 91 and 92 are stacked to form a continuous stack 93 in which the contours of the sheets 91 and 92 match.

The method of phase alignment is not particularly limited, and various methods can be adopted within the scope of the present invention. In this embodiment, in order to align the phase, the conveying path 910 of the first continuous sheet 91 and the conveying path 920 of the second continuous sheet 92 are made different in length, as shown in FIG. 9. More specifically, the conveying path 910 of the first continuous sheet 91, which is not rotated around the conveying direction MD in the rotation process, is set longer than the conveying path 920 of the second continuous sheet 92, so that the phases of the cut edges 91a and 92a of both sheets 91 and 92 in the conveying direction MD are aligned at the joining position of both conveying paths 910 and 920 (the position where the continuous laminate 93 is formed).

In the second manufacturing section 72, after forming the continuous laminate 93 as described above, as shown in FIG. 11(a), the sheets 91 and 92 are joined together to form a temporary joint 95 (temporary joining process) at the non-linear cut edge 93a of the continuous laminate 93 (the overlapping portion of the cut edge 91a and 92a of each sheet 91 and 92) that forms a protruding portion 94 that protrudes outward in the conveyance perpendicular direction CD.

If the temporary joint 95 is not formed and the joint 9 (see FIG. 1) is formed in the continuous laminate 93 by the joining means 77 (see FIG. 9) of the second manufacturing unit 72 in the next process, problems may occur such as the sheets (sheets 3A, 4, and 5 in this embodiment) constituting the convex portion 94 turning over or wrinkles appearing in the convex portion 94 during the transport of the continuous laminate 93 to the joining means 77. This is because the convex portion 94 protrudes outward in the direction perpendicular to the transport CD compared to the peripheral portion, includes a stretchable sheet 3A having stretchability in the transport direction MD, and further has a relatively low rigidity without the target tape 7 (second raw material sheet), so it is easily affected by wind pressure and vibrations caused by the transport of the continuous laminate 93, and its posture is difficult to stabilize. If the convex portion 94 becomes curled or wrinkled during transport of the continuous laminate 93 to the joining means 77, the joining means 77 may form a joint 9 on the curled or wrinkled convex portion 94, which may result in a deterioration in the appearance and bonding strength of the joint 9. The temporary bonding process increases the transport stability of the continuous laminate 93, which is an intermediate product, and can effectively prevent such inconveniences from occurring.

The temporary joint 95 is formed on a protruding portion 94 of the continuous laminate 93. The "protruding portion 94" here refers to a portion on the outer side of a virtual straight line (not shown) connecting bottoms of a pair of recesses (cut edge portions 93a of the continuous laminate 93 having the shortest length in the conveyance cross direction CD) located on both sides of a single protruding portion 94 in the continuous laminate 93 in the longitudinal direction (direction parallel to the conveyance direction MD) of the continuous laminate 93.
The temporary joint 95 is not particularly limited in its planar shape, dimensions, position, number, etc., provided that it is formed at least on the convex portion 94. However, from the viewpoint of ensuring the effect of the temporary joint 95 described above (such as the effect of improving the transport stability of the continuous laminate 93), it is preferable in the temporary joining process to form the temporary joint 95 at the top of the convex portion 94 (the cut edge portion 93a of the part of the continuous laminate 93 that has the longest length in the transport perpendicular direction CD), which is the part that is most likely to curl or wrinkle during transport in the continuous laminate 93.
In this embodiment, as shown in Fig. 11(a), one temporary bond 95 is formed on the top of each of the multiple convex portions 94 of the continuous laminate 93, and has a belt shape extending from the cut edge portion 93a in the conveyance cross direction CD in a plan view, and is formed only on the convex portion 94 and not on the target tape 7 (second raw material sheet). In the present invention, the temporary bond 95 may extend from the convex portion 94 to the target tape 7 side, and multiple temporary bond portions 95 may be formed for one convex portion 94. The length of the temporary bond 95 in the longitudinal direction (direction parallel to the conveyance direction MD) of the continuous laminate 93 is preferably 0.1 mm or more, more preferably 1 mm or more, and preferably 20 mm or less, more preferably 10 mm or less.

In this embodiment, in the temporary joining process, a temporary joint 95 having a shorter length in the conveyance perpendicular direction CD than the pair of joints 9, 9 to be formed is formed between the planned positions for forming a pair of joints 9, 9 located on both sides of the conveyance direction MD, near the planned cutting position (for example, a virtual straight line extending in the conveyance perpendicular direction CD through the top of the convex portion 94) in the sheet-forming process described later in the continuous laminate 93 (see FIG. 11(b)).

The temporary joining step is performed by the joining means 76 (see FIG. 9) provided in the second manufacturing section 72. The temporary joining section 95 is typically formed by fusing the material for the section to be formed with the temporary joining section 95 with ultrasonic waves or heat. In this embodiment, in order to carry out the method for forming the temporary joining section 95, the joining means 76 includes a melting means 760 that melts the workpiece (continuous laminate 93) with ultrasonic waves or heat, and a receiving roll 761, and is configured to be able to melt the workpiece supplied between the opposing peripheral surfaces of the melting means 760 and the receiving roll 761 while applying pressure.

After the temporary joining step, as shown in FIG. 11B, the joints 9 (see FIG. 1) are intermittently formed in the machine direction MD on the continuous laminate 93 on which the temporary joints 95 have been formed (joining step).
In this embodiment, a pair of joints 9, 9 are formed at both ends in the longitudinal direction (machine direction MD) of each unit of the elastic laminate 1 in the continuous laminate 93. More specifically, in the joining step of this embodiment, a pair of joints 9, each having a length longer in the conveyance cross direction CD than the temporary joint 95, is formed near the temporary joint 95 (top of the convex portion 94) (preferably within 20 mm, more preferably within 10 mm from the temporary joint 95) and on both sides of the temporary joint 95 in a direction parallel to the conveyance direction MD (longitudinal direction of the continuous laminate 93). In the illustrated embodiment, each of the multiple joints 9 extends along the conveyance cross direction CD over the entire length of the continuous laminate 93 in the conveyance cross direction CD.
In the continuous laminate 93 that has undergone the joining process, regions in which the distance between two adjacent joints 9, 9 in the conveying direction MD is relatively long and regions in which the distance is relatively short are arranged alternately in the conveying direction MD, the former being a region sandwiched between a pair of joints 9, 9 in a unit of elastic laminate 1, and the latter being a region sandwiched between a joint 9 of a unit of elastic laminate 1 and a joint 9 of another unit of elastic laminate 1 adjacent to it.

The joining step is performed by a joining means 77 (see FIG. 9) provided in the second manufacturing section 72. The joint 9 is typically formed by fusing the forming material of the portion to be formed with the joint 9 by ultrasonic waves or heat. In this embodiment, in order to carry out such a method of forming the joint 9, the joining means 77 is provided with a melting means 770 that melts the workpiece (continuous laminate 93) by ultrasonic waves or heat, and a receiving roll 771, and is configured to be able to melt the workpiece supplied between the opposing peripheral surfaces of the melting means 770 and the receiving roll 771 while applying pressure.

When the temporary joint 95 and the joint 9 are formed by ultrasonic or heat fusion of the forming materials of the parts to be formed, the forming conditions (fusion temperature, pressure applied to the parts to be formed, etc.) may be the same or different for the temporary joint 95 and the joint 9. Typically, it is the former, and the joining strength of the temporary joint 95 and the joint 9 is substantially the same.

In order to more reliably prevent the inconvenience of forming the joint 9 when the convex portion 94 of the continuous laminate 93 is curled or wrinkled, it is preferable to extend the temporary joint 95 outward in the conveying perpendicular direction CD after the temporary joining process and before the joining process.
The second manufacturing section 72 is equipped with a sheet pulling means 78 (FIG. 9) for carrying out the stretching process of the convex portion 94. As the sheet pulling means 78, any known means capable of pulling a continuous belt-like sheet being conveyed in a direction perpendicular to the conveying direction can be used without any particular limitation.

After the joining process, the continuous laminate 93 having the temporary joints 95 and joints 9 formed thereon is cut in the conveying direction MD while being conveyed in the conveying direction perpendicular to the conveying direction CD to obtain individual sheets of the elastic laminate 1 (single sheet process).
In this embodiment, as described above, in the joining step, a pair of joints 9 is formed near the temporary joint 95 and on both sides of the temporary joint 95 in the direction parallel to the conveying direction MD, and in the sheet-forming step, the continuous laminate 93 is cut in the conveying cross direction CD between one joint 9 and the other joint 9 constituting the pair of joints 9. In this case, as shown in Fig. 12(a), the continuous laminate 93 may be cut at the position of the temporary joint 95, or as shown in Fig. 12(b) or 12(c), the continuous laminate 93 may be cut between the temporary joint 95 and one joint 9 constituting the pair of joints 9.

Fig. 13 shows an enlarged view of one end in the direction Y of the elastic laminate 1 shown in Fig. 1. The sheet of elastic laminate 1 produced through the temporary bonding step has, in addition to a pair of joints 9, 9, a pair of temporary joints 95, 95 located outward in the direction Y from the pair of joints 9, 9. The temporary joints 95 have a shorter length in the direction X than the joints 9. The form shown in Fig. 13 is obtained by cutting the continuous laminate 93 at the positions of the temporary joints 95 as shown in Fig. 12(a) in the sheet-forming step, and temporary joints 95 are formed at both ends of the elastic laminate 1 in the direction Y.
In this embodiment, the temporary joint 95 and the joint 9 are configured with a plurality of recesses 95S, 9S intermittently arranged in one direction (direction X). The planar shape of the recesses 95S, 9S is not particularly limited, and may be, for example, a circle, an ellipse, or the like, in addition to the rectangular shape as shown in the figure. Moreover, the temporary joint 95 and the joint 9 may be a continuous linear recess instead of a collection of such a plurality of recesses, and the continuous linear recess may have a constant depth over its entire length in the longitudinal direction, or may include a plurality of types of recesses having different depths.

The present invention is not limited to the above-described embodiment, and can be modified as appropriate without departing from the spirit of the present invention.
For example, in the above embodiment, the raw sheet 90 includes sheets other than the stretch sheet 3A, but it may be composed of only the stretch sheet 3A.
In addition, in the above embodiment, in the rotation process, only one of the first continuous sheet 91 and the second continuous sheet 92 (specifically, sheet 92) was rotated 180 degrees around the conveying direction MD, but both sheets 91, 92 may be rotated together. For example, both sheets 91, 92 may be rotated 90 degrees around the conveying direction MD to align the orientations of the cut edges 91a, 92a of both sheets 91, 92.

The following supplementary notes are further disclosed regarding the above-described embodiment of the present invention.
＜1＞
A method for producing an elastic laminate comprising: a first elastic sheet having elasticity in one direction; and a second elastic sheet overlapping one side of the first elastic sheet and having elasticity in the one direction, the first elastic sheet and the second elastic sheet being joined to each other at a pair of joints formed at both ends in the one direction, the first elastic sheet and the second elastic sheet being not joined to each other at a portion sandwiched between the pair of joints, the portion sandwiched between the pair of joints being capable of forming a ring-shaped structure having elasticity in a circumferential direction,
a dividing step of dividing an original sheet including a continuous belt-like stretchable sheet that is continuous in one direction and stretched in the one direction, into a first continuous sheet including a first stretchable sheet in the conveying direction and a second continuous sheet including a second stretchable sheet in the conveying direction, the first stretchable sheet being divided into two equal parts in a direction perpendicular to the conveying direction and a direction perpendicular to the conveying direction, the cutting line meandering about a center line extending parallel to the conveying direction, while the original sheet is conveyed in the one direction as a conveying direction, and the cutting line is divided into two equal parts in a direction perpendicular to the conveying direction and a second continuous sheet including a first stretchable sheet in the conveying direction and a second continuous sheet in which a plurality of the second stretchable sheets are connected in the conveying direction;
a lamination step of overlapping the first continuous sheet and the second continuous sheet such that cut edges of both continuous sheets along the intended cutting line coincide with each other to obtain a continuous laminate;
a temporary joining step of joining the two continuous sheets that form a convex portion protruding outward in the conveyance orthogonal direction at the cut edge portion of the continuous laminate to each other to form a temporary joint;
a joining step of intermittently forming the joints in the continuous laminate in the conveying direction;
and a sheet-cutting step of cutting the continuous laminate in a direction perpendicular to the conveying direction to obtain sheets of the elastic laminate.
＜2＞
The method for producing an elastic laminate according to <1>, wherein in the temporary joining step, the temporary joining portions are formed on the tops of the convex portions.
＜3＞
The method for producing an elastic laminate described in <1> or <2>, in which the temporary bonding process is performed between planned formation positions of a pair of the joints located near the planned cutting position in the sheet-forming process in the continuous laminate and on both sides of the planned cutting position in the conveying direction, the temporary bonding portion having a length shorter in the direction perpendicular to the conveying direction than the pair of joints to be formed is formed.
＜4＞
The method for producing a stretchable laminate according to any one of <1> to <3>, wherein the temporary joint is stretched outward in the conveyance orthogonal direction after the temporary joint step and before the joint step.
＜5＞
In the sheeting process, the continuous laminate is cut in the conveying direction orthogonal to the conveying direction between one joint and the other joint that constitutes the pair of joints.
＜6＞
The method for producing a stretchable laminate according to any one of <1> to <5>, wherein the temporary joints and the joints are formed by fusing the materials forming the parts by ultrasonic waves or heat.

＜７＞
A manufacturing step of the raw sheet is included before the dividing step,
The method for producing a stretchable laminate according to any one of <1> to <6>, wherein in the raw sheet manufacturing process, a continuous belt-like first raw material sheet is arranged on one side of the stretch sheet being transported in the one direction so as to overlap the planned cutting line, and a pair of continuous belt-like second raw material sheets are arranged on both sides of the planned cutting line on the other side of the stretch sheet in the direction perpendicular to the transport direction, to obtain a raw sheet precursor, and further, the sheets constituting the raw sheet precursor are joined together.
＜8＞
The method for producing an elastic laminate described in <7>, wherein, in the manufacturing process of the raw sheet, both side edge portions along the conveying direction of the raw sheet precursor are folded back to one side of the raw sheet precursor to form a pair of folded back portions and a non-folded portion located between the pair of folded back portions.
＜9＞
The method for producing an elastic laminate described in <8>, wherein in the manufacturing process of the raw sheet, a continuous belt-shaped third raw sheet is placed in the non-folded portion of the surface of the raw sheet precursor facing the first raw sheet so as to overlap the planned cutting line.

1 Stretchable laminate 1A First stretchable sheet 1B Second stretchable sheet 2 Outer body 20 Folded portion 21 Non-folded portion portion 22 Boundary between folded portion and reinforcing sheet (third raw material sheet) 3, 3A Outer layer sheet (stretchable sheet)
31, 32 Fiber sheet 33 Elastic filament 4 Inner layer sheet (first raw material sheet)
5 Reinforcing sheet (third raw material sheet)
6. Functional sheet (fourth raw material sheet)
7 Target tape (second raw material sheet)
[0033] 8 Elastic member 9 Joint portion 10 Pants-type disposable diaper 11 Absorbent pad portion 12 Top sheet 13 Back sheet 14 Absorbent core 15 Leak-proof cuff 16 Fastening tape 17 Holder portion 70 Manufacturing apparatus for stretchable laminate 71 First manufacturing portion 72 Second manufacturing portion 73 Joining means 74 Cutting means 75 Sheet rotation areas 76, 77 Joining means 78 Sheet tensioning means 80 Raw sheet precursor 90 Raw sheet 91 First continuous sheet 91a Cut edge portion of first continuous sheet 92 Second continuous sheet 92a Cut edge portion of second continuous sheet 93 Continuous laminate 93a Cut edge portion of continuous laminate 94 Convex portion 95 Temporary joint portion CL Planned cutting line

Claims (7)

A method for producing an elastic laminate comprising: a first elastic sheet having elasticity in one direction; and a second elastic sheet overlapping one side of the first elastic sheet and having elasticity in the one direction, the first elastic sheet and the second elastic sheet being joined to each other at a pair of joints formed at both ends in the one direction, the first elastic sheet and the second elastic sheet being not joined to each other at a portion sandwiched between the pair of joints, the portion sandwiched between the pair of joints being capable of forming a ring-shaped structure having elasticity in a circumferential direction,
a dividing step of dividing an original sheet including a continuous belt-like stretchable sheet that is continuous in one direction and stretched in the one direction, into a first continuous sheet including a first stretchable sheet in the conveying direction and a second continuous sheet including a second stretchable sheet in the conveying direction, the first stretchable sheet being divided into two equal parts in a direction perpendicular to the conveying direction and a direction perpendicular to the conveying direction, the cutting line meandering about a center line extending parallel to the conveying direction, while the original sheet is conveyed in the one direction as a conveying direction, and the cutting line is divided into two equal parts in a direction perpendicular to the conveying direction and a second continuous sheet including a first stretchable sheet in the conveying direction and a second continuous sheet in which a plurality of the second stretchable sheets are connected in the conveying direction;
a lamination step of overlapping the first continuous sheet and the second continuous sheet such that cut edges of both continuous sheets along the intended cutting line coincide with each other to obtain a continuous laminate;
a temporary joining step of joining the two continuous sheets that form a convex portion protruding outward in the conveyance orthogonal direction at the cut edge portion of the continuous laminate to each other to form a temporary joint;
a joining step of intermittently forming the joints in the continuous laminate in the conveying direction;
and a sheet-cutting step of cutting the continuous laminate in a direction perpendicular to the conveying direction to obtain sheets of the elastic laminate. The method for producing an elastic laminate according to claim 1, wherein the temporary joining step forms the temporary joining portion at the top of the convex portion. The method for producing an elastic laminate according to claim 1 or 2, wherein in the temporary joining step, a temporary joint is formed between a pair of joints that are located near a planned cutting position in the continuous laminate in the sheet-forming step and on both sides of the planned cutting position in the conveying direction, and the temporary joint has a length shorter in the conveying direction than the pair of joints that are to be formed. The method for producing an elastic laminate according to any one of claims 1 to 3, wherein the temporary joint is stretched outward in the conveyance perpendicular direction after the temporary joint process and before the joining process. The method for producing an elastic laminate according to any one of claims 1 to 4, wherein in the sheeting process, the continuous laminate is cut in the conveying direction perpendicular to the conveying direction between one joint and the other joint that constitutes the pair of joints. The method for producing an elastic laminate according to any one of claims 1 to 5, wherein the temporary joints and the joints are formed by fusing the materials forming the parts by ultrasonic waves or heat. A manufacturing step of the raw sheet is included before the dividing step,
The method for producing a stretchable laminate according to any one of claims 1 to 6, wherein in the manufacturing process of the raw sheet, a continuous strip-shaped first raw material sheet is placed on one side of the stretch sheet being transported in the one direction so as to overlap the planned cutting line, and a pair of continuous strip-shaped second raw material sheets are placed on both sides of the planned cutting line on the other side of the stretch sheet in the direction perpendicular to the transport direction, to obtain a raw sheet precursor, and further the sheets constituting the raw sheet precursor are joined together.

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