CN105517519B

CN105517519B - Method for manufacturing disposable diaper and disposable diaper

Info

Publication number: CN105517519B
Application number: CN201480049249.XA
Authority: CN
Inventors: 和田隆男
Original assignee: Zuiko Corp
Current assignee: Zuiko Corp
Priority date: 2013-10-17
Filing date: 2014-10-15
Publication date: 2020-03-03
Anticipated expiration: 2034-10-15
Also published as: CN105517519A; JP6389187B2; WO2015056711A1; JPWO2015056711A1

Abstract

A base material sheet (10) composed of a continuous sheet (W) and elastic members (14) is continuously supplied in a feeding direction (A), a center-near elastic member (15) is arranged in a curved shape in which a center-near portion (C) and a side-near portion (E) are repeatedly arranged, an absorber (6) is attached to the base material sheet (10), the base material sheet (10) is divided into a web-side body sheet portion (11), a crotch-side outer sheet portion (12), and a back-side body sheet portion (13) by two dividing lines (23) along a longitudinal direction (L), the crotch-side outer sheet portion (12) is cut and divided into individual crotch-side outer bodies (7), the crotch-side outer body (7) is attached so as to straddle over the two body-side sheet portions (11, 13), the crotch-side outer body (7) is folded in two, and the body-side sheet portions (11, 13) overlapping each other are interposed between the adjacent crotch-side outer bodies (7), 13) Welded to each other and cut at the welded position.

Description

Method for manufacturing disposable diaper and disposable diaper

Technical Field

The present invention relates to a method for manufacturing a disposable diaper and a disposable diaper.

Background

Generally, a disposable diaper includes a body portion to be worn around the waist of a wearer, and a crotch portion having end portions fixed to the body portion and worn in the crotch of the wearer. The torso portion includes a torso elastic member that extends and contracts in the waist circumferential direction so as to fit the body of the wearer. On the other hand, the crotch portion includes an absorbent body and the like on the inner side (skin surface side) of the outer sheet, and leg elastic members that stretch along the side edge portions so as to fit the legs of the wearer.

In such a disposable diaper, the body portion may be manufactured while conveying the respective materials in the longitudinal direction (see, for example, patent document 1. hereinafter, referred to as prior art 1.). That is, in the above-described conventional technique 1, the body elastic member is bonded to a continuous sheet such as a nonwoven fabric continuously fed in a state of being stretched in the longitudinal direction of the continuous sheet, to form an elastic laminate, and the elastic laminate is continuously fed in the feeding direction. In this case, since the feeding direction of the elastic laminate is aligned with the extension direction of the body elastic member, the elastic laminate can be easily transported while the body elastic member is held in an extended state, and the disposable diaper can be easily continuously manufactured, which is preferable.

However, in the above-described prior art 1, since the body portion and the crotch portion are manufactured in different production lines, it is not easy to downsize the entire manufacturing facility, and since the outer body of the body portion and the crotch portion are made of different materials, the manufacturing operation is easily complicated. Further, in the case where the body portion and the crotch portion which are separately manufactured are shaped other than a rectangle in order to cover the buttocks of the wearer over a large area, when the crotch portion and the body portion having a predetermined shape are cut out from the continuous sheet, unnecessary portions need to be cut and removed, and there is a problem that waste of material (so-called trim loss) occurs.

In order to solve these problems, it has been proposed to perform the manufacturing process of the crotch part in the same production line as the manufacturing process of the body part in a process upstream of the single body dividing process of the crotch part (see, for example, patent document 2 and hereinafter referred to as prior art 2).

In the above-described conventional technique 2, a base material sheet having a predetermined width is conveyed along the continuous direction of the base material sheet, a crotch-side outer sheet portion is formed by laminating an absorbent body and a surface sheet on the crotch-side outer sheet portion, and a abdomen-side trunk portion and a back-side trunk portion are formed on both sides of the base material sheet in the width direction. The crotch portion is separated from the abdomen-side body panel portion and the back-side body panel portion in the dividing step, and the separated crotch portion is cut at a predetermined interval to be individually divided into the respective crotch portions. The crotch unit divided into individual units is attached so as to straddle the abdomen-side body portion and the back-side body portion while being rotated 90 degrees so that the longitudinal direction thereof is the width direction of the base sheet, and then the abdomen-side body portion and the back-side body portion are cut at predetermined positions to divide the individual units into individual diapers.

Prior art documents

Patent document

Patent document 1: JP2010-264283A

Patent document 2: JP2010-051667A

In the above-described prior art 2, since the abdominal-side torso part, the back-side torso part, and the crotch part are formed by dividing the single base sheet, there is an advantage that the entire manufacturing apparatus can be made compact. In addition, in the above-described conventional technique 2, when the abdomen-side body portion and the back-side body portion of the diaper divided into individual pieces are divided by the curved dividing lines which are wider from both ends toward the center portion at the time of the division generation, the adhesiveness of the disposable diaper obtained is improved.

However, in the above-described conventional technique 2, the body elastic member and the leg elastic member are arranged linearly along the conveying direction on the base sheet. Therefore, when the dividing line is curved, the side edges of the divided body panel portion and crotch portion are curved, whereas the elastic members disposed in the vicinity of the side edges are formed in a linear shape not following the curve. As a result, the disposable diaper obtained is configured such that, for example, as shown in fig. 12, the body elastic members (52) expand and contract in the horizontal plane, and the leg elastic members (53) expand and contract in the vertical plane. Therefore, the elastic members (52, 53) are stretched in a direction not along the circumferential direction of the leg (54) of the wearer, and there is a fear that the fit of the disposable diaper (51) is reduced or leakage of urine or the like occurs.

Disclosure of Invention

The invention provides a method for manufacturing a disposable diaper and the disposable diaper, which can simplify manufacturing equipment, manufacturing operation and the like, can reduce waste generated by materials, can be produced efficiently and has excellent fitting performance.

For example, the present invention is explained with reference to fig. 1 to 11 showing an embodiment of the present invention, and the present invention is configured as follows.

That is, the present invention relates to a method for manufacturing a disposable diaper having a belly-side body portion (2), a back-side body portion (3), and a crotch portion (4) extending between the body portions (2, 3), wherein the disposable diaper has an absorber (6) for absorbing excrement in the crotch portion (4),

the method for manufacturing the disposable diaper comprises the following steps:

a base material supply step (S1) in which a base material sheet (10) is continuously supplied in a feed direction (A), the base material sheet (10) being formed by laminating a continuous sheet (W) having a predetermined width and a plurality of elastic members (14) arranged along both side edges of the continuous sheet (W);

a base material dividing step (S3) in which the base material sheet (10) is divided into a belly side body sheet portion (11), a crotch side outer sheet portion (12), and a back side body sheet portion (13) along two virtual dividing lines (23, 23) extending in the longitudinal direction (L) of the base material sheet (10);

a crotch unit dividing step (S4) in which the front end portion of the crotch outer sheet portion (12) is successively cut in the longitudinal direction (L) at a predetermined cutting pitch (L1) and divided into individual crotch outer bodies (7) of a predetermined length;

a crotch portion attaching step (S5) in which the crotch portion exterior body (7) is rotated so that the crotch portion exterior body (7) is rotated by 90 DEG, and the crotch portion exterior body (7) is intermittently attached in the longitudinal direction (L) at a predetermined arrangement pitch (L2) so as to straddle the abdomen-side trunk portion panel section (11) and the back-side trunk portion panel section (13);

an absorber attaching step (S2) of attaching the absorber (6) to either the widthwise central portion of the base sheet (10) before the base dividing step (S3), the crotch portion exterior sheet portion (12) after the base dividing step (S3), or the crotch portion exterior body (7) divided into individual pieces; and

a separate diaper dividing step (S8) in which the front side body panel section (11) and the back side body panel section (13) to which the crotch outer cover (7) is attached are cut at intermediate positions between the adjacent crotch outer covers (7) to divide the disposable diapers (1) into separate disposable diapers,

the steps before the base material supply step (S1) further include: in the elastic member (14), a plurality of center-near elastic members (15) are arranged at least in a portion near the center in the width direction of the base sheet (10), the center-near elastic members (15) are arranged in a wavy curved shape in which a center-near portion (C) in which the distance from one or the other side edge of the base sheet (10) is increased and a side-near portion (E) in which the distance is decreased are repeatedly arranged at a predetermined pitch (P) in the longitudinal direction (L), and the plurality of center-near elastic members (15) are laminated,

in the substrate dividing step (S3), the substrate sheet (10) is divided such that the virtual dividing lines (23) pass through portions closer to the side edge of the substrate sheet (10) than at least a part of the center-closer portions (C) and the virtual dividing lines (23) pass through portions closer to the center side in the width direction of the substrate sheet (10) than at least a part of the side-closer portions (E) with respect to the plurality of center-closer elastic members (15).

The present invention relates to a disposable diaper manufactured by the above manufacturing method, wherein a part of a body elastic member (5) is arranged in a curved shape in the vicinity of the lower end edge of a portion of the abdomen-side body (2) and the back-side body (3) excluding at least the center portion where a crotch portion (4) is attached, and leg elastic members (8) are arranged in a curved shape in the vicinity of the side edges of at least the middle portion in the longitudinal direction of an outer covering (7) of the crotch portion (4).

Here, the "curved line shape" in which the center-near elastic member, the body-side elastic member, and the leg-side elastic member are arranged may include a straight line portion and may include a curved line portion formed by bending a straight line, but is more preferably a curved line shape having a smooth whole.

The abdomen-side body panel section, the crotch exterior panel section, and the back-side body panel section are divided from a base sheet in which a continuous sheet having a predetermined width and an elastic member are laminated. The above-described part of the material supply process is common. Therefore, the entire manufacturing facility can be downsized, and the material management, the material replacement, and the like can be simplified by sharing the material.

The center-near elastic member is arranged in a curved shape in which a side edge portion having a small distance from one side edge of the substrate sheet and a center portion having a large distance from the side edge are overlapped at a predetermined pitch. The dividing line passes through a portion closer to the side edge of the base sheet than at least a portion closer to the center of the elastic member and passes through a portion closer to the center of the base sheet in the width direction than at least a portion closer to the side edge of the elastic member. Therefore, in the vicinity of the lower edge of the part of the abdomen-side body portion and the back-side body portion of the obtained disposable diaper except at least the center portion where the crotch portion is attached, a part closer to the center elastic member is arranged in a curved shape as a part of the body elastic member, and a part closer to the center elastic member is arranged in a curved shape as the leg elastic member in the vicinity of each side edge of the outer covering of the crotch portion. These curved body elastic members and leg elastic members are connected to each other in a ring shape, and thereby expand and contract in the circumferential direction around the legs of the wearer or in a direction close thereto. As a result, the disposable diaper has improved fitting properties, and leakage of urine or the like is suppressed.

Drawings

Fig. 1 is a partially cut-away front view of a disposable diaper according to a first embodiment of the present invention.

Fig. 2 is a system diagram of a manufacturing process of the disposable diaper according to the first embodiment.

Fig. 3 is an explanatory view showing a manufacturing procedure of the disposable diaper of the first embodiment.

Fig. 4 is an explanatory view of the substrate dividing step of the first embodiment.

Fig. 5 is an explanatory view of the crotch unit dividing step and the crotch attachment step of the first embodiment.

Fig. 6 is an explanatory view of the substrate dividing step according to the second embodiment of the present invention.

Fig. 7 is an explanatory view of a crotch attachment step of the second embodiment.

Fig. 8 is an explanatory view showing a substrate supply step in a third embodiment of the present invention.

Fig. 9 is an explanatory view of the substrate dividing step according to the fourth embodiment of the present invention.

Fig. 10 is a schematic configuration diagram of an X-X line cross section of fig. 9.

Fig. 11 is an explanatory view of a crotch attachment step of the fourth embodiment.

Fig. 12 is a schematic front view of a disposable diaper of prior art 2.

Detailed Description

The disposable diaper obtained by the above-described production method has an H-shaped developed state. In this H-shaped disposable diaper, the crotch portion is folded in two, and the ends of the abdomen-side body portion and the back-side body portion are opposed to each other, and the opposed ends are fixed to each other as necessary, and then packaged in a packaging step. In this case, the ends of the torso part may be fixed to each other by adhesion or the like so as not to be separable, or may be detachably fixed by using a fixing mechanism such as a surface fastener.

The disposable diaper is preferably configured such that the abdomen-side body portion, the back-side body portion, and the crotch portion have the same length, and the entire base sheet can be effectively used without waste when the abdomen-side body portion, the back-side body portion, and the crotch portion are obtained.

The dividing lines are not limited to a specific shape, and may be formed in a straight line along the longitudinal direction, for example, in which case the dividing device can be configured to be simple and easy to divide. In the present invention, the dividing line may be curved along the center-near elastic member, or may be a large distance from one or the other side edge of the substrate sheet at the center-near portion and a small distance at the side-near edge portion.

When the body portion sheet portion and the crotch exterior sheet portion are divided by two curved dividing lines, the body portion having a wide intermediate portion width and the crotch exterior body having a narrow intermediate portion width can be formed without cutting unnecessary portions from the obtained body portion sheet portion and crotch exterior sheet portion. The dividing line is curved along the central elastic member, and the elastic members of the body panel portion and the crotch outer panel portion divided in the dividing step are along the side edges of the curved line. Thus, a disposable diaper having excellent fitting properties can be obtained, and efficient production can be achieved with less material waste.

The elastic member disposed on the continuous sheet may be an elastic member that expands and contracts in a predetermined direction, and may be an umbilical member and/or a ribbon.

The center-adjacent elastic members of the elastic members may be arranged in one or more rows on one side edge side half and on the other side edge side half in the width direction of the continuous sheet.

The plurality of center-adjacent elastic members may be arranged in the curved shape in parallel with each other on one side edge side half and the other side edge side half of the continuous sheet. The two dividing lines may be set to be curved lines passing through the elastic members arranged in parallel. In this case, the center-near elastic members are respectively body elastic members in the divided abdominal-side body panel portion and back-side body panel portion, and are respectively leg elastic members in the vicinity of both side edges of the crotch outer panel portion. Therefore, the elastic members for the body and the leg portions are arranged on the continuous sheet in a single step, and the steps can be further simplified.

The linear or curved dividing line may be set to pass through a portion closer to the side edge of the substrate sheet than the center portion and pass through a portion closer to the center in the width direction of the substrate sheet than the side edge portion, with respect to the center-closer elastic member. At this time, the center-side elastic member is cut along a dividing line between the center-side portion and the side edge portion. Therefore, the center-side elastic members are formed as the body elastic members in the side edge portions of the abdomen-side body portion and the back-side body portion, and the leg elastic members in the center-side portions of the crotch outer sheet portion in the vicinity of the side edges.

In a typical disposable diaper, an absorber is disposed in a portion overlapping a crotch portion of a body portion. Therefore, it is not preferable that the stretching force of the body elastic member acts, and the body elastic member in that portion may be subjected to a measure to cancel the stretching force. However, if the dividing line is set to cut the center-near elastic member as described above, the center-near elastic member does not remain in the portion of the body panel sections where the crotch outer cover is attached, and therefore, it is not necessary to cancel the stretching force of the center-near elastic member, and the stretching force of the center-near elastic member can be used without waste at all.

The crotch outer-covering sheet portion may be cut at an arbitrary position in the crotch unit dividing step. However, when the dividing line is curved, the divided crotch outer sheet portion has a shape in which wide portions and narrow portions are arranged in an overlapping manner, and when the wide portion is cut, the intermediate portion of the crotch portion divided into individual crotch portions is narrowed. That is, in the disposable diaper obtained, the vertical width of the central portion to which the crotch unit is attached is larger than the vertical width of the opposite end portions, and the width of the outer package of the crotch unit increases from the central portion in the longitudinal direction toward the opposite end portions. As a result, the disposable diaper is shaped to follow the circumference of the wearer's legs.

When the dividing line is curved, the crotch unit outer sheet portion is cut at the center of the wide portion and divided into individual units in the crotch unit dividing step, and the front side and the back side of the obtained crotch unit outer body are formed in the same shape. In contrast, when the crotch outer sheet portion is cut and divided into individual pieces at a position separated from the center of the wide portion in the longitudinal direction, the areas of the front side and the back side of the crotch outer body are different from each other, and for example, the absorption capacity of one absorbent body is increased, or the back side is enlarged to be well fitted over the hip of the wearer.

Preferably, the two dividing lines may form the crotch outer package to be symmetrical to each other.

The abdomen-side body panel and the back-side body panel may each have a shape in which wide portions and narrow portions are repeatedly arranged at predetermined pitches. In the crotch attachment step, when the wide portions of the body panel portions are opposed to each other and the respective end portions of the crotch outer cover are attached to the wide portions, the central portion of the body of the disposable diaper to be obtained is formed to have a wide width and can be satisfactorily fitted around the buttocks of the wearer.

In the present invention, in the crotch attachment step, the wide portion of the abdomen-side body panel portion and the narrow portion of the back-side body panel portion may be opposed to each other by shifting one waist-side body panel portion by a half pitch phase in the longitudinal direction, and the ends of the crotch exterior body may be attached to the wide portion of the one body-side body panel portion and the narrow portion of the other body-side body panel portion, respectively.

The base sheet is not limited to a specific material and structure, and one or more kinds of nonwoven fabric, synthetic resin sheet, and the like may be used alone or in combination.

For example, the base sheet (10) may be configured such that an outer continuous sheet (W1) and an inner continuous sheet (W2) narrower than the width thereof are laminated to each other, the plurality of elastic members (14) are arranged at the laminated portion of the continuous sheets (W1, W2), both side edges of the outer continuous sheet (W1) are exposed as extended portions (W3) to the outside of the side edges of the inner continuous sheet (W2),

after the crotch attachment step (S5), the outer continuous sheet (W1) may be bent along the side edge of the inner continuous sheet (W2), and the extended portion (W3) may be laminated on the inner continuous sheet (W2).

In this case, the upwardly extending portions of the outer sheet are folded back at the upper end edges of the body portions and are stacked on the upper portion of the inner sheet. As a result, the disposable diaper is formed in a state in which the upper end edges of the abdomen-side body and the back-side body are covered with the outer continuous sheet, and there is no fear of peeling at the upper end edges, and the disposable diaper is relatively beautiful.

In this case, the respective ends in the longitudinal direction of the crotch portion are disposed between the extended portions of the outer sheet and the inner sheet, and leakage of urine or the like can be further satisfactorily prevented.

Further, as the inner continuous sheet, two inner continuous sheets that are disposed apart from each other on one side edge side and the other side edge side of the base sheet may be used, and each inner continuous sheet may have a sheet-like cuff on a side end portion on the central portion side of the base sheet.

In this case, a part of the inner continuous sheet constituting the base sheet also serves as a sheet rib, and a disposable diaper having the sheet rib on both side portions of the crotch portion can be manufactured at low cost.

The absorber mounting step may be performed at any time before the disposable diaper is divided into individual components. For example, the absorbent body may be attached to each of the crotch outer covers fixed to the body panel after the crotch attachment step. The absorbent body may be attached to the center portion of the base sheet in the width direction at a predetermined interval before the base dividing step, or may be attached to the crotch outer sheet portion at a predetermined interval after the base dividing step. In these cases, the top sheet made of a liquid-permeable sheet can be continuously supplied and attached in a state covering the absorbent body, or the back sheet made of a liquid-impermeable sheet can be continuously supplied and attached between the absorbent body and the base sheet or the like.

Features that are described and/or illustrated in connection with one of the above-described embodiments or the following examples can be used in the same way or in a similar way in one or more other embodiments or other examples, and/or in combination with or instead of the features of the other embodiments or examples.

Examples

The invention will be more clearly understood from the following description of an ideal embodiment with reference to the accompanying drawings. However, the embodiments and the drawings are only for illustration and description and should not be used to limit the scope of the present invention. The scope of the invention is limited only by the claims. In the drawings, like reference numerals designate identical or corresponding parts throughout the several views.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Fig. 1 to 5 show a first embodiment of the present invention.

As shown in fig. 1, the disposable diaper (1) has a ventral torso part (2), a dorsal torso part (3), and a crotch part (4) that spans between intermediate parts of the torso parts (2, 3). The abdomen-side body (2) and the back-side body (3) are each formed of an elastic laminate in which body elastic members (5) are laminated on a sheet (W) such as a nonwoven fabric, and each end of the abdomen-side body (2) is fixed to a corresponding end of the back-side body (3) by welding or the like. The crotch section (4) has an absorbent body (6) for absorbing excrement on the inside of the crotch section outer cover (7), and leg elastic members (8) are arranged along both side edges of the crotch section outer cover (7).

The disposable diaper (1) is manufactured by a manufacturing method including the following steps, for example, as shown in fig. 2 and 3.

Substrate supply step (S1): the substrate sheet (10) is continuously fed in a feeding direction (A).

Absorber mounting step (S2): the absorbent body (6) is attached to the middle portion of the base sheet (10) in the width direction.

Substrate dividing step (S3): the base sheet (10) is divided into a belly-side body sheet portion (11), a crotch-side exterior sheet portion (12), and a back-side body sheet portion (13) along two imaginary dividing lines (23, 23) extending in the longitudinal direction (L).

Crotch unit dividing step (S4): the crotch portion outer sheet portion (12) is cut at predetermined intervals (cutting pitch) (L1) and divided into individual crotch portion outer bodies (7).

Crotch portion attachment step (S5): after the crotch outer covering (7) is rotated by a predetermined angle (90 degrees), the crotch outer covering is attached to the longitudinal direction (L) at predetermined intervals (arrangement pitch) (L2) so as to straddle the abdomen-side body panel (11) and back-side body panel (13).

Folding step (S6): the crotch outer cover (7) is folded in half so that the abdomen-side body panel section (11) and the back-side body panel section (13) are superposed on each other.

Bonding step (S7): the abdomen-side body panel section (11) and the back-side body panel section (13) are welded and fixed to each other at an intermediate position between the adjacent crotch outer covering (7).

Diaper individual dividing step (S8): the abdomen-side body panel (11) and the back-side body panel (13) are cut at the position where the welding is performed, and the disposable diapers (1) are divided into individual pieces.

As shown in fig. 2 and 3, the substrate sheet (10) continuously fed in the feeding direction (a) in the substrate feeding step (S1) includes two continuous sheets (W) made of nonwoven fabric having a predetermined width and an elastic member (14) sandwiched between the two sheets (W) in a state of being elongated in the longitudinal direction, and each of the continuous sheets (W) and the elastic member (14) are fixed to each other by an adhesive such as a hot melt adhesive.

The elastic member (14) includes a body elastic member (5) disposed on the side edge side of the base sheet (10), and a leg elastic member (8) disposed on the center side. The material of the elastic member (14) can be polyurethane, natural rubber, thermoplastic resin, or the like. In addition, the shape may be linear, ribbon-like, or the like. One or more elastic members (14) may be used. When a thermoplastic resin is used as a material, a hot melt adhesive may not be necessary when the thermoplastic resin itself has a function of bonding to the continuous sheet (W). The body elastic member (5) and the leg elastic member (8) may have the same material and shape or may have different materials and shapes.

In the half of one side edge side and the half of the other side edge side of the base sheet (10), a plurality of, for example, two elastic members (15, 15) of the elastic members (14) disposed near the center in the width direction of the base sheet (10) are disposed in parallel with each other in a curved shape. The curved line is formed such that a center-near portion (C) having a large distance from one or the other side edge of the substrate sheet (10) and a side-near portion (E) having a small distance are repeatedly arranged at a predetermined pitch (P) in the longitudinal direction (L). That is, the plurality of elastic members (15) are provided in parallel with each other in each of a half including one side edge and a half including the other side edge. The elastic members (15) disposed on one half of the one side edge portion and the elastic members (15) disposed on the other half of the other side edge portion are disposed in line symmetry with each other along a wave-shaped curve having a predetermined pitch (P) (wavelength) that is the same as each other and is close to each other in a center portion (C) and is distant from each other in a side edge portion (E). Of the two center-adjacent elastic members (15, 15) arranged in parallel, the elastic member (15) on the center side of the base sheet constitutes the leg elastic member (8), and the elastic member (15) on the side edge side of the base sheet constitutes a part of the body elastic member (5).

In the absorber mounting step (S2), a back sheet (16) made of a liquid-impermeable material is bonded in advance to the middle portion of the base sheet (10) in the width direction, and the absorber (6) is mounted and arranged at predetermined intervals with the back sheet (16) therebetween. For example, as shown in fig. 2, in the absorbent body forming step (S9), pulp (17) is pulverized by a pulverizer (18), and the fluff after defibration is laminated on a pattern drum (19) to produce the absorbent body (6). As the liquid-impermeable material, for example, a polyethylene film, a nonwoven fabric having hydrophobicity and air permeability, and the like are preferable.

When the absorbent body (6) is attached, a top sheet (20) made of a liquid-permeable material covering the absorbent body (6) and sheet-like cuffs (21) disposed on both sides of the absorbent body (6) are attached to the base sheet (10). The rib (21) is generated by a rib forming step (S10) as shown in fig. 2, for example. As the liquid-permeable material constituting the top sheet (20), for example, liquid-permeable nonwoven fabric, mesh sheet, and the like are preferable.

A transfer sheet (transfer sheet) is interposed between the top sheet (20) and the absorbent body (6) as needed, and the transfer sheet rapidly diffuses urine and the like and prevents the absorbed urine and the like from leaking from the top sheet (20).

Further, a super absorbent polymer may be mixed with the fluff of the absorbent body (6). In this case, the absorbent body (6) may also be wrapped with tissue paper (tissue) so that the super absorbent polymer does not overflow from the fluff. In the present invention, the absorbent body may be configured by supporting a super absorbent polymer on a nonwoven fabric or the like.

As shown in fig. 3, the base material sheet (10) to which the absorbent body (6) is attached is cut along two virtual dividing lines (23, 23) by a dividing device (22) in the base material dividing step (S3), and is divided into three parts, namely, a abdomen-side body sheet part (11), a crotch-side outer sheet part (12), and a back-side body sheet part (13), in order from one side edge toward the other side edge.

More specifically, as shown in fig. 4, each of the dividing lines (23) is set to pass through the two center-adjacent elastic members (15) arranged in parallel. Therefore, the dividing lines (23) are set to be in a curved shape in which the center-near portion (C) of the center-near elastic member (15) having an increased distance from the side edge of the base sheet (10) and the side-near portion (E) having a decreased distance are repeatedly arranged at the predetermined pitch (P). That is, the pair of curved dividing lines (23) are set to be line-symmetrical with each other while showing a predetermined pitch (P) (wavelength) waveform in which they are close to each other near the center portion (C) and apart from each other near the side edge portion (E). In this case, the waveform of the dividing line (23) and the waveform of the elastic member (15) may be set to have the same amplitude and phase. As a result, the obtained body panel sections (11, 13) and the crotch outer panel section (12) are configured such that the wide sections and the narrow sections are arranged repeatedly at the pitch (P).

Of the center-near elastic members (15), the elastic member closer to the center of the continuous sheet (W) than the dividing line (23) is disposed as a leg-elastic member (8) in the vicinity of the side edge of the crotch outer sheet portion (12). Elastic members on the side edge side of the continuous sheet (W) with respect to the dividing line (23) are arranged as body elastic members (5) in the vicinity of the curved side edges of the body sheet portions (11, 13).

As shown in fig. 5, in the crotch portion outer sheet section (12), the crotch portion single body dividing step (S4) is performed by cutting the absorbent bodies (6) adjacent to each other at predetermined intervals (L1) by a cutting device (24), and the crotch portion outer sheet section is divided into individual crotch portion outer bodies (7). The predetermined length (L1), i.e., the length of the crotch outer package (7), is set to a size equal to the pitch (P). The cutting position is set at a position shifted (separated) from the central part along the length direction (L) in the wide part of the crotch outer sheet part (12). The width of the obtained crotch outer package (7) increases from the center in the longitudinal direction (L) toward both ends, and the area of one end side is larger than the area of the other end side. Leg elastic members (8) are disposed along curved side edges in the vicinity of both side edges of the crotch outer package (7).

In the first embodiment, the cutting position is shifted in the longitudinal direction (L) from the center of the wide portion. However, in the present invention, the cutting may be performed at the center of the wide portion of the crotch outer sheet portion (12).

As shown in fig. 3 and 5, the crotch outer covering (7) divided into individual pieces is rotated by 90 degrees by a transfer device (25) in the crotch attachment step (S5), and then attached at intervals of a predetermined length (L2) in the longitudinal direction so as to straddle the abdomen-side body panel (11) and back-side body panel (13). That is, one end on the narrow-area side of the crotch outer covering (7) is fixed to the center of the wide portion of the abdomen-side body panel (11), and the other end on the wide-area side is fixed to the center of the wide portion of the back-side body panel (13). The wide portions of the two torso part sheet portions (11, 13) are arranged repeatedly at the pitch (P), and the predetermined length (L2) of the attachment interval is equal to the size of the pitch (P).

In the first embodiment, the other end portion on the wide area side of the crotch unit outer cover (7) is fixed to the wide portion of the back-side body panel section (13), and therefore, the disposable diaper obtained can be satisfactorily fitted over the hips of the wearer. However, in the present invention, the other end portion on the wide area side of the crotch unit outer cover (7) may be fixed to the abdomen-side body panel portion (11), and the absorbent body (6) disposed inside the crotch unit outer cover (7) may have a large area, thereby increasing the absorption capacity on the abdomen side of the disposable diaper.

In the first embodiment, the abdomen-side trunk portion (11) and the back-side trunk portion (13) are set to have the same width dimension. However, in the present invention, for example, the back-side body panel (13) may be formed to have a width wider than that of the abdomen-side body panel (11) to wrap the buttocks of the wearer well.

In fig. 3, the crotch outer covering (7) stretched over the two torso panel portions (11, 13) is folded in two by the folding device (26) in the folding step (S6) so that the abdomen-side torso panel portion (11) and the back-side torso panel portion (13) are overlapped with each other. Then, in the joining step (S7), the body panel sections (11, 13) are fixed to each other by welding with a sealing device (27) at intermediate positions between the adjacent crotch outer covers (7). Thereafter, in the diaper individual dividing step (S8), the welded portions are cut by a cutting device (28) to produce individual disposable diapers (1).

After that, the disposable diaper (1) divided into individual pieces is changed to an appropriate posture by the reversing device (29) of fig. 2, and then is sent to the next packaging step.

As shown in fig. 1, the disposable diaper (1) divided into individual pieces is formed in a state in which the cut end of the abdomen-side body (2) and the cut end of the back-side body (3) are fused and fixed to each other, and is formed in a loop shape by both the body portions (2, 3).

The cutting position as the welding position is set at the middle position between the adjacent crotch portion outer covering bodies (7) in fig. 4, and the interval between the adjacent crotch portion outer covering bodies (7) is equal to the pitch (P). Therefore, the length of both body parts (2, 3) of the disposable diaper (1) obtained by the manufacturing method is formed to be equal to the pitch (P). On the other hand, the length of the crotch outer package (7) is set to a size equal to the pitch (P). Therefore, the abdomen-side body (2), back-side body (3), and crotch (4) of the disposable diaper (1) are equal in length to each other.

Each end of the crotch outer package (7) in fig. 5 is fixed to the wide portion of the abdomen-side trunk panel (11) and the wide portion of the back-side trunk panel (13), respectively. Therefore, the body parts (2, 3) of the disposable diaper (1) in fig. 1 are configured such that the vertical width at the center part where the crotch part (4) is attached is wider than the vertical width at the both end parts.

The dividing line (23) in fig. 3 is set in a curved shape along the center elastic member (15). Therefore, in the disposable diaper (1) of fig. 1, the body elastic member (5) is arranged in a curved shape along the lower end edges of the body portions (2, 3) in the vicinity of the lower end edges.

As described above, the crotch outer package (7) is wider from the center portion in the longitudinal direction toward both ends, and the leg elastic members (8) are arranged in a curved shape along the side edges in the vicinity of the side edges. Therefore, as shown in fig. 1, in the disposable diaper (1), the elastic members (14) are arranged in a curved shape along the lower end edges of the torso parts (2, 3) and the both side edges of the crotch part (4), respectively, and are formed in a ring shape so as to be connected to each other. Therefore, these elastic members (14) are stretched in the circumferential direction of the wearer's legs (30) or in the direction close thereto.

In the first embodiment, the dividing line is set between a pair of center-located elastic members. However, in the present invention, for example, as in the second embodiment shown in fig. 6 and 7, the dividing line (23) may be set to cross the center elastic member.

That is, in the second embodiment, as in the first embodiment, two elastic members (15, 15) arranged closer to the center in the width direction among the elastic members (14) arranged on the base sheet (10) are arranged in a curved shape in which a center-side portion (C) where the distance from the side edge of the base sheet (10) increases and a side-side portion (E) where the distance decreases are repeatedly arranged at a predetermined pitch (P) in the longitudinal direction (L). In the case of this embodiment, the waveform of the dividing line (23) has the same phase and the same wavelength (pitch (P)) as the waveform of the elastic member (15), but the amplitude of the waveform of the dividing line (23) may be smaller than the amplitude of the waveform of the elastic member (15).

However, in the case of this second embodiment, unlike the first embodiment, in the substrate dividing step (S3), the dividing line (23) is set so as to pass through a portion closer to the side edge of the substrate sheet (10) than the central elastic member (15) in the central portion (C) and pass through a portion closer to the center of the substrate sheet (10) than the central elastic member (15) in the side edge portion (E). Therefore, the dividing line (23) crosses the elastic member (15) between the center-side portion (C) and the side-edge portion (E). As a result, the side edge portions (E) of the center elastic members (15) are disposed as the body elastic members (5) in the narrow portions of the abdomen-side body panel portion (11) and the back-side body panel portion (13), and the center portions (C) are disposed as the leg elastic members (8) in the vicinity of both side edges of the crotch outer panel portion (12).

The crotch portion outer sheet portion (12) obtained by the division is divided into individual crotch portion outer bodies, and then attached by a transfer device (25) at intervals of a predetermined length (L2) in the longitudinal direction so as to straddle the abdomen-side body panel portion (11) and the back-side body panel portion (13) in a crotch portion attaching step (S5) as shown in fig. 7. The crotch outer covering (7) is fixed to the wide portions of the body sheet portions (11, 13), but the center elastic member (15) does not remain in the wide portions. Therefore, it is not necessary to eliminate the stretching force of the elastic member (15) near the center at the portion where the crotch outer cover (7) is attached, and the stretching force of the elastic member (15) near the center can be effectively used without generating waste at all. As shown in fig. 7, a center elastic member (15) is arranged over the entire circumference along the periphery of a hole for inserting a leg of a wearer, so-called leg hole (leg hole), and a disposable diaper having excellent fit is obtained through the same subsequent steps as in the first embodiment. The number of the center-approaching elastic members (15) is not limited to a specific number, and may be one or three or more. Other structures of the second embodiment are the same as those of the first embodiment, and the description thereof is omitted.

In the present invention, when the dividing line is set in a curved shape, the wide portion of the abdomen-side body panel portion and the narrow portion of the back-side body panel portion may face each other, and the crotch exterior body may be attached so as to straddle one of the wide portions and the other of the narrow portions.

In the present invention, the elastic member may be sandwiched between one continuous sheet having a predetermined width and two continuous sheets having a narrow width arranged along each side edge. Further, both side edges of a single wide continuous sheet may be folded back inward, and the elastic member may be sandwiched between the folded-back portions to form a base sheet having a predetermined width.

In the first embodiment, a back sheet, a top sheet, a sheet rib (also referred to as a side sheet, a three-dimensional gather, or the like), and the like are laminated on the base sheet. However, in the present invention, at least any one of these laminated sheets may also be used as a continuous sheet constituting the substrate sheet.

For example, in the first embodiment, the continuous sheet is composed of a nonwoven fabric or the like. However, in the present invention, at least one of the continuous sheets may be constituted by a liquid-impermeable sheet, and the continuous sheet may also serve as a back sheet, for example.

Further, for example, as in the third embodiment shown in fig. 8, the base sheet (10) may be constituted by one continuous sheet (W) having a predetermined width and the outer edge portion (21a) of the sheet rib (21) disposed inside the continuous sheet. That is, in this third embodiment, an elastic member (14) is disposed on the side edge side of one continuous sheet (W) having a predetermined width, and the absorber (6) is attached to the middle portion in the width direction of the elastic member (14) via a pattern roll (19) via a back sheet (16). A surface sheet (20) and sheet-like beads (21) fixed along both side edges thereof are disposed above the absorber (6). The elastic member (14) is interposed between the outer edge (21a) of the rib top (21) and the continuous sheet (W). Therefore, the outer edge part (21a) of the rib opening (21) forms a part of the continuous sheet (W). The base sheet (10) is formed by the outer edge (21a), the continuous sheet (W) of the predetermined width, and an elastic member (14) therebetween. The reference numeral (21b) denotes a rib elastic body disposed at an inner edge portion of the rib (21). Other structures of the third embodiment are the same as those of the first embodiment, and illustration and description thereof are omitted.

In the present invention, in the third embodiment, the base sheet may be formed by using the outer edge portion of the surface sheet as a continuous sheet in place of the outer edge portion of the rib top, and sandwiching the elastic member between the outer edge portion of the surface sheet and the continuous sheet of the predetermined width. In these cases, the continuous sheet having the predetermined width may also serve as a back sheet, and the number of sheets to be stacked can be further reduced.

As in the fourth embodiment shown in fig. 9 to 11, the dividing line may be set to be linear.

In the fourth embodiment, as shown in fig. 9, a plurality of central elastic members (15) are arranged in parallel in a curved shape in each of a half of the substrate sheet (10) on one side edge side and a half of the substrate sheet (10) on the other side edge side. The curved elastic members (15) are repeatedly arranged at a predetermined pitch (P) in the longitudinal direction (L) at a center portion (C) and a side edge portion (E) in the same manner as in the first embodiment. On the other hand, two dividing lines (23, 23) dividing the substrate sheet (10) into three parts are formed in straight lines parallel to each other along the longitudinal direction (L) of the substrate sheet (10).

Therefore, in the fourth embodiment, not only the structure of the dividing device (22) for dividing is simple, but also the alignment between the curved shape of the central elastic member (15) and the curved shape of the dividing line (23) is not required, and the dividing operation is easy to perform.

The dividing lines (23) are set so as to penetrate through the center-near elastic member (15) in the half of the side edge of the substrate sheet (10) at the side edge side of the substrate sheet (10) and at the side edge side of the substrate sheet (10) at the side edge side of the center-near elastic member (C) and at the side edge side of the side edge-near portion (E).

The center-side elastic member (15) is cut between the center-side portion (C) and the side edge-side portion (E) along the dividing line (23). Thus, the side edge portions (E) of the center elastic members (15) are disposed as the body elastic members (5) in the vicinity of the side edges of the abdomen-side body panel portion (11) and the back-side body panel portion (13), while the center portions (C) are disposed as the leg elastic members (8) in the vicinity of the side edges of the crotch-side outer panel portion (12).

As shown in fig. 11, in the case of this embodiment, almost no central elastic body remains in the portions of the body panel portions (11, 13) to which the crotch outer cover (7) is attached.

The curved body elastic member (5) and the leg elastic member (8) are arranged in a ring shape so as to be connected to each other. Therefore, these curved elastic members (5, 8) are stretched in the circumferential direction around the wearer's legs or in the direction close thereto.

As shown in fig. 9, the base sheet (10) includes an outer continuous sheet (W1) and two inner continuous sheets (W2) having a width smaller than that of the outer continuous sheet. As shown in fig. 9 and 10, between the two continuous sheets (W1, W2), a plurality of elastic members (14) are disposed on the lateral sides in the width direction, and a back sheet (16), an absorbent body (6), and a top sheet (29) are disposed in this order from the outside in the center portion in the width direction. Both side edges of the surface sheet (29) are welded to the middle portion of each inner continuous sheet (W2) at welding portions (31). The inner continuous sheets (W2) are formed into sheet-like beads (21) at portions thereof inside the welded portions (31), and the sheet-like beads (21) include bead elastic members.

The extended portions (W3) of the both side edges of the outer continuous sheet (W1) protrude outward beyond the side edges of the inner continuous sheet (W2). The base sheet (10) is divided into three parts along the dividing line (23), and then the crotch outer sheet part (12) is cut at predetermined intervals (L1) to cut out the crotch outer body (7). After being rotated by 90 degrees, the crotch exterior body (7) is attached at intervals of a predetermined length (L2) so as to straddle the abdomen-side trunk panel portion (11) and the back-side trunk panel portion (13), as shown in fig. 11. After the crotch attachment step (S5), the outer continuous sheet (W1) is folded along the side edge of the inner continuous sheet (W2), and the extended portion (W3) overlaps the inner continuous sheet (W2).

The disposable diaper obtained by the above-described steps is formed in a state in which the upper edges of the abdomen-side body and back-side body are covered with the outer continuous sheet (W1), and therefore, there is no fear that the upper edges will peel off.

Other structures of this embodiment are the same as those of the first and third embodiments described above, and illustration and description thereof are omitted.

The method of manufacturing a disposable diaper described in each of the above examples is exemplified to embody the technical idea of the present invention, and the shape, size, material, manufacturing procedure, and the like of each member are not limited to the contents of the embodiment, and various modifications can be added within the scope defined by the claims of the present invention.

For example, in the first embodiment, the absorbent body is attached to the central portion of the base sheet before being divided in the base dividing step. In the present invention, however, the absorbent body may be attached to the crotch portion outer sheet portion obtained by the division in the base material dividing step, or the absorbent body may be attached to the crotch portion outer sheet divided into individual pieces, such as the respective crotch portion outer sheets fixed to the body portion sheet portion.

In the first embodiment described above, the case of manufacturing a so-called pants-type disposable diaper was described, but the present invention may also be applied to manufacturing a so-called pull-up pants-type disposable diaper.

In the present invention, the constituent materials, sizes, shapes, and the like of the continuous sheet, the elastic member, the absorbent body, and the like are not limited to those of the above-described embodiments.

Industrial applicability

The present invention can be applied to a disposable diaper and its manufacture.

Description of reference numerals:

1: disposable diaper 2: ventral torso portion 3: back side trunk portion 4: the crotch part 5: body elastic member 6: absorber 7: crotch outer package 8: leg elastic member 10: substrate sheet 11: abdomen-side trunk portion sheet portion 12: crotch outer sheet portion 13: back side body panel portion 14: elastic member 15: the center elastic member 23: dividing line A: the feeding direction C: toward the center portion E: side edge portion L: length direction L1: cutting pitch (predetermined length at the time of cutting) L2: arrangement pitch (predetermined length at the time of mounting) P: spacing S1: substrate supply step S2: absorber mounting step S3: substrate dividing step S4: crotch unit dividing step S5: crotch portion attaching step S8: diaper individual dividing step W: continuous sheet W1: outer continuous sheet W2: inner continuous sheet W3: extension arrangement part

Claims

1. A method for manufacturing a disposable diaper having an abdomen-side body (2), a back-side body (3), and a crotch unit (4) that is laid over the abdomen-side body (2) and the back-side body (3), wherein the disposable diaper is provided with an absorber (6) that absorbs excrement in the crotch unit (4),

the method for manufacturing a disposable diaper is characterized in that,

a crotch unit dividing step (S4) in which the front end portion of the crotch outer sheet portion (12) is cut one by one in the longitudinal direction (L) at a predetermined cutting pitch (L1) and divided into a single crotch outer body (7) of a predetermined length;

in the substrate dividing step (S3), the dividing line (23) is set so as to pass through a portion closer to the side edge of the substrate sheet (10) than the center-closer elastic member (15) in the center-closer portion (C), and pass through a portion closer to the center of the substrate sheet (10) than the center-closer elastic member (15) in the side edge-closer portion (E).

2. The method for manufacturing a disposable diaper according to claim 1,

in the substrate dividing step (S3), the dividing lines (23) divide the substrate sheet (10) so as to form straight lines extending in the longitudinal direction (L).

3. The method for manufacturing a disposable diaper according to claim 1,

in the substrate dividing step (S3), the dividing line (23) divides the substrate sheet (10) as follows:

the dividing line (23) is formed in a curved shape along the wave shape of the center-near elastic member (15), and the distance between the dividing line (23) and the side edge of the one or the other of the substrate sheets (10) is large at the center-near portion (C), and the distance is small at the side edge-near portion (E).

4. The method for manufacturing a disposable diaper according to claim 3,

the substrate sheet (10) includes a plurality of elastic members in which the central elastic members (15) are respectively arranged in parallel, in one half including one side edge and the other half including the other side edge, and the curved dividing lines (23) divide the substrate sheet (10) so as to divide the elastic members (15) arranged in parallel into two groups.

5. The method for manufacturing a disposable diaper according to claim 3,

in the crotch unit dividing step (S4), the crotch outer sheet portion (12) is cut and divided into individual units at positions spaced apart by a predetermined dimension in the longitudinal direction (L) from the center portion in the longitudinal direction (L) in the side edge portions (E).

6. The method for manufacturing a disposable diaper according to any one of claims 1 to 5,

the dividing line (23) is formed so as to pass through a portion closer to the side edge of the base sheet (10) than the center-closer portion (C) and pass through a portion closer to the center in the width direction of the base sheet (10) than the side edge-closer portion (E) with respect to the center-closer elastic member (15).

7. The method for manufacturing a disposable diaper according to any one of claims 1 to 5,

the base sheet (10) is configured such that an outer continuous sheet (W1) and an inner continuous sheet (W2) narrower than the width thereof are laminated on each other, the plurality of elastic members (14) are arranged at the laminated portion of the continuous sheets (W1, W2), and both side edges of the outer continuous sheet (W1) are exposed to the outside as extended portions (W3) than the side edges of the inner continuous sheet (W2),

after the crotch attachment step (S5), the outer continuous sheet (W1) is bent along the side edge of the inner continuous sheet (W2), and the extended portion (W3) is laminated on the inner continuous sheet (W2).

8. The method for manufacturing a disposable diaper according to claim 7,

two inner continuous sheets (W2) that are disposed apart from each other on one side edge side and the other side edge side of the base sheet (10) are used as the inner continuous sheet (W2), and each inner continuous sheet (W2) has a sheet rib (21) at each side end on the central portion side of the base sheet (10).

9. A disposable diaper produced by the production method according to any one of claims 1 to 5,

the disposable diaper is characterized in that,

a part of the body elastic member (5) is arranged in a curved shape in the vicinity of the lower edge of the abdomen-side body (2) and the back-side body (3) except at least the center part where the crotch part (4) is attached,

leg elastic members (8) are respectively arranged in a curved shape in the vicinity of each side edge of at least a middle portion in the longitudinal direction of the crotch outer covering (7).

10. The disposable diaper according to claim 9,

the abdomen-side trunk part (2), the back-side trunk part (3), and the crotch part (4) are set to have equal lengths.

11. The disposable diaper according to claim 9,

at least one of the abdomen-side trunk part (2) and the back-side trunk part (3) is configured such that the width in the vertical direction of the central part to which the crotch part (4) is attached is wider than the width in the vertical direction of both end parts,

the crotch unit outer cover (7) is wider from the center in the longitudinal direction toward both ends.

12. The disposable diaper according to claim 9,

the abdomen-side torso part (2) and the back-side torso part (3) each include an outer continuous sheet (W1), an inner continuous sheet (W2), and an elastic member (14) sandwiched between the two continuous sheets (W1, W2), wherein an upwardly extending portion (W3) of the outer continuous sheet (W1) is folded back at an upper end edge of each of the torso parts (2, 3) and is laminated on an upper portion of the inner continuous sheet (W2), and each end portion in the longitudinal direction of the crotch part (4) is sandwiched between the extending portion (W3) of the outer continuous sheet (W1) and the inner continuous sheet (W2).