WO2018042558A1

WO2018042558A1 - Folding method

Info

Publication number: WO2018042558A1
Application number: PCT/JP2016/075513
Authority: WO
Inventors: 弘志一色; 翔太石川
Original assignee: ユニ・チャーム株式会社
Priority date: 2016-08-31
Filing date: 2016-08-31
Publication date: 2018-03-08
Also published as: JP6725543B2; JPWO2018042558A1

Abstract

Provided is a folding method for stably folding an absorber while maintaining the shape of an absorbent material. The folding method relates to a method for folding an absorber (40), which includes an absorbent material and has a longitudinal direction and a width direction perpendicular to the longitudinal direction, while conveying the absorber (40) along the longitudinal direction. The absorber (40) includes a first low basis weight region (42a) that extends in the longitudinal direction and a pair of high basis weight regions (44) that adjoin both sides of the first low basis weight region (42a) in the width direction. The folding method includes a folding step of folding the absorber (40) along folding lines (FL1a, FL1b) that run along the first low basis weight region (42a) in an area between the pair of high basis weight regions (44).

Description

Folding method

The present invention relates to a folding method for folding an absorbent body while conveying the absorbent body having a longitudinal direction and a width direction orthogonal to the longitudinal direction along the longitudinal direction.

Patent Document 1 discloses a folding device that folds a web continuously extending in one direction. The folding device folds a side region along the conveyance direction of the web conveyed along the conveyance direction onto a central region in the orthogonal direction (direction orthogonal to the conveyance direction) of the web.

JP 2011-50478 A

The inventor of the present application examined folding the absorbent body used in the absorbent article along a line along the longitudinal direction of the absorbent body in order to improve the functionality of the absorbent article such as a disposable diaper. Here, as for the absorber used for an absorbent article, the basic weight of an absorbent material is relatively lower than the low basic weight area | region and the low basic weight area | region where the basic weight of an absorbent material is relatively low or does not have an absorbent material. And a high basis weight region. When folding the absorber which has a low basic weight area | region and a high basic weight area | region, the inventor of this application discovered that the following subjects arise.

That is, when trying to fold the absorber, a strong load is applied to the absorber on the fold line in the process of bending the absorber. Therefore, if the fold line crosses the boundary between the low basis weight region and the high basis weight region or passes through a portion of the high basis weight region close to the low basis weight region, The absorbent material in the basis weight region may be pushed out to the low basis weight region, and the absorbent material in the high basis weight region may collapse. When the absorbent material in the high basis weight region collapses, the basis weight distribution of the absorbent material varies on the folding line. Thus, if the absorber is to be folded based on the line where the distribution of the basis weight of the absorbent material varies, the folding line may be distorted in the width direction and the absorber may not be stably folded.

Therefore, a folding method capable of stably folding the absorbent body while maintaining the shape of the absorbent material is desired.

The folding method according to one aspect relates to a folding method of folding an absorbent body while conveying the absorbent body including an absorbent material and having a longitudinal direction and a width direction orthogonal to the longitudinal direction along the longitudinal direction. The absorber includes a first low basis weight region extending in the longitudinal direction and a pair of high basis weight regions adjacent to both sides of the first low basis weight region in the width direction. The folding method includes a folding step of folding the absorbent body along a fold line along the first low basis weight region in a region between the pair of high basis weight regions.

According to the present invention, the absorber can be stably folded while maintaining the shape of the high weight area and the low weight area.

FIG. 1 is a plan view of the absorbent body before being folded. 2 is a cross-sectional view of the absorbent body taken along line 2A-2A in FIG. FIG. 3 is a schematic diagram showing a schematic configuration of a folding method for folding the absorber. FIG. 4 is a plan view showing an example of an adhesive application region in the application step. FIG. 5 is a perspective view showing the configuration of the folding device. FIG. 6 is a plan view seen from the 6A direction of FIG. FIG. 7 is a plan view showing the folding step. FIG. 8 is a sectional view taken along line 8A-8A in FIG. FIG. 9 is a sectional view taken along line 9A-9A in FIG. FIG. 10 is a diagram illustrating the position of the fold line formed in the absorber. FIG. 11 is a plan view showing an adhesive application region in the application step according to the second embodiment. 12 is a cross-sectional view showing a cross section of the folded absorbent body when an adhesive is applied to the application region shown in FIG. FIG. 13 is a plan view showing a folding step according to the third embodiment. FIG. 14 is a plan view of an absorbent article including a folded absorbent body. FIG. 15 is a cross-sectional view of the absorbent article taken along the line 15A-15A in FIG.

(1) Outline of Embodiments At least the following matters will become apparent from the description of the present specification and the accompanying drawings.

A folding method according to an aspect is a folding method of folding an absorbent body while conveying an absorbent body including an absorbent material and having a longitudinal direction and a width direction orthogonal to the longitudinal direction along the longitudinal direction. The absorber includes a first low basis weight region extending in the longitudinal direction and a pair of high basis weight regions adjacent to both sides of the first low basis weight region in the width direction, and the folding method. Comprises a folding step of folding the absorbent body along a fold line along the first low basis weight region in a region between the pair of high basis weight regions.

According to this aspect, the fold line for folding the absorber extends along the first low basis weight region in the region between the pair of high basis weight regions. Specifically, the fold line extends along the first low basis weight region on the first low basis weight region or on the boundary between the first low basis weight region and the high basis weight region.

The low basis weight area is generally softer than the high basis weight area. Therefore, the absorbent body can be stably folded because the fold line extends along the first low basis weight region in the region between the pair of high basis weight regions.

In particular, the rigidity of the high basis weight region is generally higher than the rigidity of the first low basis weight region. That is, the first low basis weight region is sandwiched between the relatively high rigidity high basis weight regions. Since the fold line is located in a region between the pair of high basis weight regions, a strong load is applied to the region between the pair of high basis weight regions during the folding step. Therefore, the absorbent material in the high basis weight region is unlikely to collapse toward the first low basis weight region. In addition, since the first low basis weight area is sandwiched between a pair of relatively high rigidity, a shape of the first low basis weight area even if a load is applied to the first low basis weight area. Is also relatively stable. Therefore, the absorbent material is not easily broken during the folding step, and the basis weight distribution of the absorbent material is less likely to vary on the fold line. Since the absorbent body can be folded with the basis weight distribution of the absorbent material on the fold line being uniform, the absorbent body can be folded stably.
Therefore, it is possible to fold the absorbent body stably while maintaining the shape of the absorbent material.

According to a preferred aspect, the region between the pair of high basis weight regions is equally divided into three in the width direction, and the region located in the center in the width direction of the region between the pair of high basis weight regions is When defined as a central region, the fold line is located outside the central region.

The rigidity of the high basis weight region is generally higher than that of the low basis weight region. Therefore, a rigidity difference is generated on the boundary between the high basis weight region and the low basis weight region. The line where this stiffness difference occurs extends in the longitudinal direction intermittently or continuously along the low basis weight region.

The region near the line where the rigidity difference occurs is a region where the absorber is easily bent. In this aspect, since the folding line is located in a region where the absorber is easily bent, the absorber can be folded more stably.

According to a preferred aspect, the folding method includes a first pressing step of pressing the absorber in the thickness direction before the folding step.

The thickness (maximum thickness) of the absorber is reduced by pressing the absorber before the folding step. Thereby, it is possible to make the absorbent body easier to break than the absorbent body before pressing.

According to a preferred aspect, at least before the first pressing step, the thickness of the high basis weight region is larger than the thickness of the low basis weight region.

Thereby, in the first pressing step, the high basis weight region is pressed more strongly than the low basis weight region, and the rigidity of the high basis weight region is further increased. Thereby, the difference of the rigidity of a high basic weight area | region and the rigidity of a low basic weight area | region becomes larger. By increasing the rigidity difference, it becomes easier to fold the absorbent body more stably in the region near the boundary between the high basis weight region and the low basis weight region.

According to a preferred aspect, the folding method includes a second pressing step of pressing the absorber in the thickness direction after the folding step.

By pressing the absorber after the folding step, the absorber can be strongly marked, and the shape of the absorber can be stably maintained.

According to a preferred aspect, the first low basis weight region continuously extends in the longitudinal direction.

This makes the basis weight distribution of the absorbent material more uniform along the fold line. Therefore, the absorber can be folded more stably.

According to a preferred aspect, the folding method includes an application step of applying an adhesive to a folding range hidden inside the absorber by folding the absorber at the fold line before the folding step. .

Since the folding range can be fixed with an adhesive, the shape of the folded absorbent body can be maintained more stably.

According to a preferred aspect, in the application step, the adhesive is applied to the first low basis weight region.

According to this aspect, after the absorber is folded, the layer to which the adhesive is applied does not overlap twice, so that the total thickness of the adhesive layer can be suppressed from increasing. Thereby, it can suppress that the part to which the adhesive agent was apply | coated becomes hard too much, Therefore, a soft absorber can be provided.

According to a preferred position aspect, in the application step, the adhesive is applied to the absorbent body in a state where a coating machine for applying the adhesive is separated from the absorbent body.

Temporarily, when an adhesive is applied to the absorbent body while pressing the absorbent body, the adhesive is likely to ooze into the absorbent body. In some cases, the adhesive oozes out from the back side of the absorber, and the adhesive may adhere to a member constituting the absorber folding device.

According to this aspect, since the absorbent body is not pressed when the adhesive is applied to the absorbent body, it is possible to suppress the adhesive from seeping out from the back side of the absorbent body and adhering to the members constituting the folding device. .

According to a preferred aspect, the absorbent body has a cover sheet that wraps the absorbent material, and the cover sheet is bonded to the absorbent material with an adhesive.

According to this aspect, the absorbent material is wrapped and held by the cover sheet. Therefore, it can suppress that the shape of a high basic weight area | region and a low basic weight area | region collapses. Thereby, an absorber can be folded more stably, maintaining the shape of an absorber.

According to a preferred aspect, the absorbent body includes a second low basis weight region extending in the longitudinal direction, and a pair of high basis weight regions adjacent to both sides of the second low basis weight region, In the folding step, after folding the absorber at the fold line along the first low basis weight region in a region between a pair of high basis weight regions adjacent to both sides of the first low basis weight region, The absorber is folded at a fold line along the second low basis weight region in a region between a pair of high basis weight regions adjacent to both sides of the second low basis weight region.

According to this aspect, it is not necessary to simultaneously deform both sides in the width direction of the absorber during the folding step. Thereby, an absorber can be folded beautifully along a fold line.

According to a preferred aspect, the absorbent body includes a second low basis weight region extending in the longitudinal direction, and a pair of high basis weight regions adjacent to both sides of the second low basis weight region, In the folding step, at the same time as the absorbent body starts to be folded at the fold line along the first low basis weight region in a region between a pair of high basis weight regions adjacent to both sides of the first low basis weight region. Before the folding, the absorber is folded at a fold line along the second low basis weight region in a region between a pair of high basis weight regions adjacent to both sides of the second low basis weight region.

According to this aspect, since both sides in the width direction of the absorbent body are bent at the same time during the folding step, the absorbent body is prevented from shifting in the width direction. Thereby, it is suppressed that the position of a fold line shifts in the width direction. Further, the time required for the folding step can be shortened as compared with the case where the two foldings are performed at different timings.

(2) First Embodiment Hereinafter, a folding method according to a first embodiment will be described 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. However, it should be noted that the drawings are schematic and ratios of dimensions and the like are different from actual ones. Therefore, specific dimensions and the like should be determined in consideration of the following description. Moreover, the part from which the relationship and ratio of a mutual dimension differ also in between drawings may be contained.

The folding method according to the present embodiment relates to a method for folding the absorber. The absorbent body folded by the main folding method can be used as a component of an absorbent article such as a disposable diaper or a sanitary napkin.

FIG. 1 is a plan view of the absorbent body before being folded. 2 is a cross-sectional view of the absorbent body taken along line 2A-2A in FIG. The absorber 40 has a longitudinal direction L and a width direction W orthogonal to the longitudinal direction L. In the present embodiment, the absorbent body 40 extends continuously in the longitudinal direction L, and is not cut into lengths that are applied to individual articles in the longitudinal direction L.

The absorber 40 includes an absorbent material 41 that absorbs a liquid such as urine, and a cover sheet 46 that wraps the absorbent material 41. The absorbent material 41 includes at least one of hydrophilic fiber, pulp, and superabsorbent polymer.

The cover sheet 46 may have a first sheet 46a and a second sheet 46b. The first sheet 46 a covers one surface of the absorbent material 41. The second sheet 46b is provided on the opposite side of the absorbent material 41 from the first sheet 46a. Both end portions of the second sheet 46b in the width direction W are folded back toward the first sheet 46a and cover the end portions of the first sheet 46a in the width direction. The 1st sheet | seat 46a and the 2nd sheet | seat 46b can be comprised by a nonwoven fabric or tissue, or those combinations.

The cover sheet 46 is preferably bonded to the absorbent material with an adhesive 50. Specifically, it is preferable that both the first sheet 46 a and the second sheet 46 b are bonded to the absorbent material by the adhesive 50.

The absorber 40 includes a first low basis weight region 42a, a second low basis weight region 42b, and high

basis weight regions

44a, 44b, 44c. The high

basis weight regions

44a, 44b, and 44c are regions including the absorbent material 41 having a larger basis weight than the first low basis weight region 42a and the second low basis weight region 42b. The 1st low basic weight area | region 42a and the 2nd low basic weight area | region 42b are the area | regions containing the absorber 41 whose basic weight is smaller than the high basic weight area |

region

44a, 44b, 44c, or the basic weight of an absorber is substantially zero. It is an area. Here, the basis weight of the absorbent material is substantially zero as long as the basis weight of the designed absorbent material is zero, and means a concept including a small amount of absorbent material mixed in the manufacturing process. FIG. 2 shows an example of an absorbent body in which the first low basis weight region 42a and the second low basis weight region 42b substantially do not include the absorbent material 41.

The thickness of the 1st low basic weight area | region 42a and the 2nd low basic weight area | region 42b may be thicker than the thickness of the high basic weight area |

regions

44a, 44b, 44c. Moreover, the thickness of the 1st low basic weight area | region 42a and the 2nd low basic weight area | region 42b may be substantially the same as the thickness of the high basic weight area |

regions

44a, 44b, 44c.

The first low basis weight region 42a and the second low basis weight region 42b extend along the longitudinal direction L. Preferably, the first low basis weight region 42a and / or the second low basis weight region 42b extends continuously in the longitudinal direction L.

The high

basis weight regions

44a and 44b are provided adjacent to both sides of the first low basis weight region 42a in the width direction W. Further, the high

basis weight regions

44b and 44c are provided adjacent to both sides of the second low basis weight region 42b in the width direction W.

In the absorber 40 according to the first embodiment, the high

basis weight regions

44a, 44b, 44c continuously extend in the longitudinal direction L. Instead, the high

basis weight regions

44a, 44b, 44c may be provided intermittently in the longitudinal direction L. That is, the high

basis weight areas

44a, 44b, and 44c may be configured by a plurality of areas separated in the longitudinal direction L.

FIG. 3 is a schematic diagram showing a schematic configuration of a folding method for folding the absorber. The folding method includes a first pressing step S1, a coating step S2, a folding step S3, and a second pressing step S4. In the first pressing step S1, the absorber 40 described above is pressed in the thickness direction. In the application step S <b> 2, an adhesive is applied to a partial area on the absorber 40. In the folding step S3, the absorber 40 is folded along the longitudinal direction L. In the second pressing step S4, the folded absorbent body 40 is pressed in the thickness direction. A series of these steps S1 to S4 is performed while transporting the absorber 40 in the transport direction MD. The transport direction MD is the same direction as the longitudinal direction L of the absorber 40. Hereinafter, each step will be described in detail.

First, the first pressing step S1 is performed before the folding step S3. In the first pressing step S1, the absorber 40 described above is pressed in the thickness direction. As an example, the absorber 40 is pressed in the thickness direction by a pair of

rollers

200 and 202 facing each other. By pressing the absorber 40 before the folding step S3, the thickness (maximum thickness) of the absorber 40 is reduced. Thereby, in the folding step S3, the absorber 40 can be more easily folded.

The first pressing step S1 is an optional step and may be performed as necessary.

Next, an application step S2 for applying an adhesive on the absorber is performed. A coating machine 300 for applying an adhesive is provided on a transport path for transporting the absorber. The coating machine 300 is located away from the absorber 40 conveyed on the conveyance path. The coating machine 300 discharges the adhesive toward the absorber 40 being conveyed. It is preferable that the coating machine 300 apply | coat an adhesive agent to the absorber 40 in the state away from the absorber.

If the adhesive is applied to the absorbent body 40 while pressing the coating machine 300 against the absorbent body 40, the adhesive will ooze into the absorbent body, and in some cases, the adhesive may ooze from the back side of the absorbent body 40. is there. Thereby, an adhesive agent may adhere to members, such as a roller which conveys the absorber 40. FIG. According to this embodiment, since the absorber 40 is not pressed when the adhesive is applied to the absorber 40, the adhesive hardly oozes from the back side of the absorber 40. Therefore, it can suppress that an adhesive agent adheres to the member which comprises the apparatus which enforces a folding method.

FIG. 4 shows an example of the application area of the adhesive 54 discharged by the coating machine 300. The adhesive 54 is applied to at least a partial region within the folding range of the absorber 40. Here, the folding range of the absorber 40 is defined by the range hidden inside the absorber 40 by folding the absorber 40 in the folding step S3. That is, the folding range of the absorber 40 is a range that is not exposed on the surface of the absorber 40 after the folding step S3. Since the adhesive 54 is applied to at least a partial region within the folding range of the absorber 40, the folding range of the absorber 40 can be firmly fixed with the adhesive 54 after the folding step S3. Therefore, the shape of the folded absorber 40 can be stably maintained.

In addition, application | coating step S2 is an arbitrary step and should just be implemented as needed.

Next, a folding step S3 for folding the absorber is performed. FIG. 5 is a perspective view showing an example of the configuration of the folding device. FIG. 6 is a plan view seen from the 6A direction of FIG. The folding device includes a transport mechanism 150 that transports the absorber 40, a first guide plate 140, and a second guide plate 142.

The transport mechanism 150 may include a transport belt 153 and a suction mechanism 157. The conveyor belt 153 is an endless belt wound around a pair of

rollers

151 and 152. The conveyor belt 153 has a suction hole 155. The suction mechanism 157 sucks the absorber 40 through the suction hole 155 of the transport belt 153. Thereby, the absorber 40 is sucked and held on the transport belt 153.

When the folding line of the absorber 40 is formed in the first low basis weight region 42a and the second low basis weight region 42b, the region between the first low basis weight region 42a and the second low basis weight region 42b, that is, The high basis weight region 44b is preferably sucked and held on the conveyor belt 153. Thereby, the area | region where the absorber 40 is not return | folded can be hold | maintained to the conveyance belt 153 firmly.

The first guide plate 140 and the second guide plate 142 are arranged at positions away from the conveyor belt 153 in the direction orthogonal to the conveyor belt 153. That is, there is a gap between the conveyor belt 153 and the first guide plate 140. Similarly, there is a gap between the conveyor belt 153 and the second guide plate 142.

The first guide plate 140 folds one side (first side) 40a in the width direction W of the absorber 40 on the conveyor belt 153 (see FIG. 7). The second guide plate 142 folds the other side portion (second side portion) 40b in the width direction W of the absorber 40 on the conveyor belt (see FIG. 7).

The first guide plate 140 extends along the conveyance direction MD. One end portion 140e of the first guide plate in the cross direction CD orthogonal to the transport direction MD is inclined from the outside to the inside of the absorber in the width direction as it goes downstream.

The second guide plate 142 extends along the conveyance direction MD. One end portion 142e of the second guide plate in the cross direction CD orthogonal to the transport direction MD is inclined from the outside to the inside of the absorber in the width direction as it goes downstream.

FIG. 7 is a plan view showing the folding step S3 according to the present embodiment. FIG. 8 is a sectional view taken along line 8A-8A in FIG. FIG. 9 is a sectional view taken along line 9A-9A in FIG. 8 and 9, the cross section of the absorber 40 is schematically drawn for the sake of simplicity.

When the absorber 40 passes through the region where the first guide plate 140 and the second guide plate 142 are provided, the absorber 40 is sucked and held by the transport belt 153. When the absorber 40 enters the first guide plate 140 and the second guide plate 142, the first side portion 40a and the second side portion 40b of the absorber, that is, the high

basis weight regions

44a and 44c of the absorber 40, respectively. It is placed on the first guide plate 140 and the second guide plate 142 (see FIG. 8). At this time, the high basis weight region 44 b located at the center of the absorber 40 is sucked and held on the transport belt 153 by the suction hole 155. The absorber 40 is conveyed downstream, and the end portion 140e of the first guide plate and the end portion 142e of the second guide plate approach the center of the absorber 40 in the width direction W. Thereby, the edge part 140e of a 1st guide plate will push the area | region between a pair of high basic weight area |

regions

44a and 44b to the inner side of the width direction (refer FIG. 9). Therefore, as shown in FIG. 9, the absorber 40 is an area between the pair of high

basis weight areas

44a and 44b, and is folded into a Z shape in a sectional view. Similarly, the end 142e of the second guide plate pushes the region between the pair of high

basis weight regions

44b and 44c inward in the width direction (see FIG. 9). Therefore, as shown in FIG. 9, the absorber 40 is an area between the pair of high

basis weight areas

44b and 44c and is folded into a Z shape in a cross-sectional view. In addition, the absorber 40 may be folded so that the edge part inside the high basic weight area |

regions

44a and 44c in the width direction W may be mounted on the high basic weight area | region 44b.

The position of the first guide plate 140 is the first low basis weight region 42a in the region between the pair of high

basis weight regions

44a and 44b where the first fold lines FL1a and FL1b formed on the first side portion 40a of the absorbent body are located. Is set to extend along the line. Here, the region between the pair of high

basis weight regions

44a and 44b means the boundary between the first low basis weight region 42a or the first low basis weight region 42a and the high

basis weight regions

44a and 44b. .

Similarly, the position of the second guide plate 142 is such that the second fold lines FL2a and FL2b formed on the second side portion 40b of the absorber are in the second low basis weight in the region between the pair of high

basis weight regions

44b and 44c. It is set so as to extend along the quantity region 42b. Here, the region between the pair of high

basis weight regions

44b and 44c means the boundary between the second low basis weight region 42b or the second low basis weight region 42b and the high

basis weight regions

44b and 44c. .

In the present embodiment, the absorber 40 is folded at a fold line along the low

basis weight regions

42a and 42b in a region between the pair of high

basis weight regions

44a, 44b, and 44c. The low

basis weight regions

42a, 42b are generally softer than the high

basis weight regions

44a, 44b, 44c. Therefore, the folding lines FL1a, FL1b, FL2a, and FL2b extend along the low

basis weight regions

42a and 42b in the region between the pair of high

basis weight regions

44a, 44b, and 44c, so that the absorber 40 can be stabilized. Can be folded.

In particular, the rigidity of the high

basis weight regions

44a, 44b, 44c is generally higher than the rigidity of the low

basis weight regions

42a, 42b. In other words, the low

basis weight regions

42a and 42b are sandwiched between the high

basis weight regions

44a, 44b and 44c having relatively high rigidity. Since the fold lines FL1a, FL1b, FL2a, FL2b are located in a region between the pair of high

basis weight regions

44a, 44b, 44c, during the folding step S3, between the pair of high

basis weight regions

44a, 44b, 44c. A heavy load is applied to the area. Therefore, the absorbent material in the high

basis weight regions

44a, 44b, 44c is unlikely to collapse toward the low

basis weight regions

42a, 42b. Further, since the low

basis weight regions

42a and 42b are sandwiched between a pair of relatively high rigidity high

basis weight regions

44a, 44b and 44c, even if a load is applied to the low

basis weight regions

42a and 42b, the low

basis weight regions

42a and 42b are low. The shapes of the

grammage areas

42a and 42b are also relatively stable. Therefore, during the folding step S3, the absorbent material is not easily collapsed, and the basis weight distribution of the absorbent material is less likely to vary on the folding lines FL1a, FL1b, FL2a, FL2b. Since the absorbent body can be folded while the basis weight distribution of the absorbent material on the folding lines FL1a, FL1b, FL2a, and FL2b is uniform, the absorbent body 40 can be folded stably.

Further, when the basis weight of the absorbent material in the low

basis weight regions

42a and 42b is substantially zero, the shape of the absorbent material is not substantially collapsed, and the absorber 40 can be folded more stably. . Therefore, it is possible to fold the absorbent body stably while maintaining the shape of the absorbent material.

Further, when the absorber 40 extends continuously long in the longitudinal direction L, the shape of the absorber 40 on the upstream side easily deforms following the shape of the absorber 40 folded on the downstream side. Therefore, it becomes easier to fold the absorbent body 40 than to fold the absorbent body 40 divided into individual product lengths.

A position where the absorber 40 is folded, that is, a more preferable position of the fold lines FL1a, FL1b, FL2a, FL2b will be described with reference to FIG. FIG. 10 is a diagram illustrating the position of the fold line formed in the absorber. FIG. 10 is an enlarged view showing a state in which the absorber 40 folded in the folding step S3 is developed. In FIG. 10, two dotted lines that divide the region between a pair of high basis weight regions, that is, the low

basis weight regions

42 a and 42 b into three equal parts in the width direction W are shown. Here, a region located at the center in the width direction of the region between the pair of high basis weight regions is defined as a central region Rc. A region located on the side portion in the width direction of the region between the pair of high basis weight regions is defined as a side region Re.

The folding lines FL1a, FL1b, FL2a, FL2b are preferably located outside the central region Rc in the region between the pair of high

basis weight regions

44a, 44b, 44c.

The rigidity of the high

basis weight regions

44a, 44b, 44c is generally higher than the rigidity of the low

basis weight regions

42a, 42b. Therefore, a rigidity difference is generated on the boundary between the high

basis weight regions

44a, 44b, 44c and the low

basis weight regions

42a, 42b. When the high

basis weight regions

44a, 44b, and 44c continuously extend in the longitudinal direction, the line in which this rigidity difference occurs continuously extends in the longitudinal direction L along the low

basis weight regions

42a and 42b. Instead, when the high

basis weight regions

44a, 44b, and 44c extend intermittently in the longitudinal direction, the line in which this rigidity difference occurs intermittently along the low

basis weight regions

42a and 42b in the longitudinal direction. Extend to L.

The side region Re is a region where the absorber 40 is easily bent due to the difference in rigidity. As shown in FIG. 10, when the folding lines FL1a, FL1b, FL2a, FL2b are located outside the central region Rc, the absorber 40 is easily bent, and the absorber 40 can be folded more stably.

Further, the folding lines FL1a, FL1b, FL2a, FL2b may be located at the boundaries between the low

basis weight regions

42a, 42b and the high

basis weight regions

44a, 44b, 44c, respectively. In this case, the absorber 40 can be folded more beautifully at the folding lines FL1a, FL1b, FL2a, FL2b due to the difference in rigidity between the low

basis weight regions

42a, 42b and the high

basis weight regions

44a, 44b, 44c.

Moreover, in this embodiment, the area | region between the two folding lines FL1a and FL1b is the low basic weight area | region 42a. Similarly, a region between the two folding lines FL2a and FL2b is a low basis weight region 42b. When folded in a Z shape in cross-sectional view, a strong load is likely to be applied to the region between the two fold lines, and the region between the two fold lines is preferably a relatively soft low basis weight region.

At least before the first pressing step S1, the thickness of the high

basis weight regions

44a, 44b, 44c is preferably larger than the thickness of the low

basis weight regions

42a, 42b. In this case, in the first pressing step S1, the high

basis weight regions

44a, 44b, 44c are pressed more strongly than the low

basis weight regions

42a, 42b, and the rigidity of the high

basis weight regions

44a, 44b, 44c is further increased. Thereby, the difference between the rigidity of the high

basis weight regions

44a, 44b, 44c and the rigidity of the low

basis weight regions

42a, 42b becomes larger. By increasing the rigidity difference, it becomes easier to fold the absorbent body 40 more stably in a region near the boundary between the high

basis weight regions

44a, 44b, 44c and the low

basis weight regions

42a, 42b.

When the first low basis weight region 42a and / or the second low basis weight region 42b extends continuously in the longitudinal direction L, the distribution of the basis weight of the absorbent material along the folding lines FL1a, FL1b, FL2a, FL2b Becomes more uniform. Therefore, the absorber 40 can be folded more stably.

When the cover sheet 46 is bonded to the absorbent material 41 with the adhesive 50, the absorbent material 41 is wrapped and covered firmly with the cover sheet 46. Therefore, it can suppress that the shape of the high basic weight area |

regions

44a, 44b, 44c, the 1st low basic weight area | region 42a, and the 2nd low basic weight area | region 42b collapses. Thereby, an absorber can be folded more stably, maintaining the shape of an absorber.

In the first embodiment, in the folding step S3, a fold line FL1a along the first low basis weight region 42a in a region between a pair of high

basis weight regions

44a and 44b adjacent to both sides of the first low basis weight region 42a. , FL1b, the second low basis weight region in the region between the pair of high

basis weight regions

44b, 44c adjacent to both sides of the second low basis weight region 42b at the same time as the absorber starts to be folded or before the folding is finished. The absorber 40 is folded at fold lines FL2a and FL2b along the line 42b. That is, the period for folding the first side portion 40a of the absorber 40 overlaps at least partially with the period for folding the second side portion 40b of the absorber 40.

Thereby, during the folding step S3, both sides in the width direction W of the absorber 40 are bent at the same time, so that an external force is applied to the absorber 40 from both sides in the width direction toward the center. Therefore, the absorber 40 is suppressed from shifting in the width direction W. As a result, the positions of the folding lines FL1a, FL1b, FL2a, FL2b are suppressed from shifting in the width direction. Furthermore, compared with the case where the 1st side part 40a of the absorber 40 and the 2nd side part 40a of the absorber 40 are folded at a separate timing, the time concerning folding step S3 can be shortened.

Also, as described above, it is preferable that the adhesive 54 is applied to the folded range of the absorbent body 40 before the folding step S3 (application step S2). In the aspect shown in FIG. 4, the adhesive 54 is provided across the first low basis weight region 42 a and the high basis weight region 44 b. In this case, as shown in FIG. 9, the adhesive 54 overlaps the two layers in a state where the first side portion 40 a and the second side portion 40 b of the absorber 40 are folded. In this case, the shape of the folded absorber 40 is more easily maintained.

It is preferable to implement 2nd press step S4 which presses the absorber 40 in thickness direction after folding step S3. The absorber 40 is pressed by being sandwiched between a pair of pressing

rollers

400 and 402, for example. By pressing the absorber 40 after the folding step S3, a fold can be strongly attached to the absorber 40, and the shape of the folded absorber can be stably maintained.

The second pressing step S4 is an optional step and may be performed as necessary.

After the second pressing step S4, the absorber 40 is cut so as to have a predetermined length in the longitudinal direction L. Thereby, a plurality of absorbers having a predetermined length can be obtained. The absorbent body thus obtained can be applied to absorbent articles such as disposable diapers and sanitary napkins. In this case, the absorber folding method described above can be used as one step in the method of manufacturing an absorbent article. That is, the apparatus shown in FIG. 3 can be applied as a part of a production line for absorbent articles. In addition, the manufacturing method of an absorbent article can be implemented by a well-known method except the method of folding the absorber mentioned above.

(3) Second Embodiment Next, a folding method according to a second embodiment will be described. In the second embodiment, descriptions of the same configurations and steps as those in the first embodiment may be omitted.

The folding method according to the second embodiment may include a first pressing step S1, a coating step S2, a folding step S3, and a second pressing step S4, as in the first embodiment. However, the application area | region of the adhesive agent 54 in application | coating step S2 differs from the thing of 1st Embodiment. Hereinafter, the application area | region of the adhesive agent 54 which concerns on 2nd Embodiment is demonstrated using FIG.11 and FIG.12.

FIG. 11 is a plan view showing an application region of the adhesive 54 in the application step according to the second embodiment. 12 is a cross-sectional view showing a cross section of the absorbent body after the folding step S3 when the adhesive 54 is applied to the application region shown in FIG.

The adhesive 54 is provided only in the first low basis weight region 42a and the second low basis weight region 42b within the folding range of the absorber 40. In this case, as shown in FIG. 12, the adhesive 54 does not overlap with the first side portion 40 a and the second side portion 40 b of the absorber 40 being folded. Since the layer to which the adhesive 54 is applied does not overlap twice, it is possible to suppress an increase in the total thickness of the adhesive 54. Thereby, it can suppress that the part to which the adhesive agent 54 was apply | coated becomes hard too much, Therefore, the soft absorber 40 can be provided.

(4) Third Embodiment Next, a folding method according to a third embodiment will be described. In the third embodiment, the description of the same configurations and steps as those in the first embodiment may be omitted.

The folding method according to the third embodiment may include a first pressing step S1, a coating step S2, a folding step S3, and a second pressing step S4, as in the first embodiment. However, in the folding step S3, the timing of folding the first side portion 40a and the second side portion 40b of the absorber 40 is different from that of the first embodiment. Hereinafter, folding step S3 according to the third embodiment will be described with reference to FIG.

FIG. 13 is a plan view showing a folding step according to the third embodiment. In the third embodiment, the folding device includes a first guide plate 140 and a second guide plate 142. The first guide plate 140 folds one side portion (first side portion) 40 a in the width direction W of the absorber 40 on the transport belt 153. The second guide plate 142 folds the other side portion (second side portion) 40b in the width direction W of the absorber 40 on the transport belt.

The configurations of the first guide plate 140 and the second guide plate 142 are the same as those in the first embodiment. However, in the third embodiment, the first guide plate 140 and the second guide plate 142 are separated from each other in the transport direction L.

In the folding step S3, a first fold line of the absorbent body is formed along a fold line along the first low basis weight region 42a in a region between a pair of high

basis weight regions

44a and 44b adjacent to both sides of the first low basis weight region 42a. After folding the side portion 40a, the absorbent body is a fold line along the second low basis weight region 42b in a region between a pair of high

basis weight regions

44b and 44c adjacent to both sides of the second low basis weight region 42b. Fold the first side 40b.

According to this aspect, it is not necessary to simultaneously deform (bend) both the first side portion 40b and the second side portion 40b of the absorber during the folding step. Therefore, since the side part of an absorber can be correctly folded one by one, the absorber 40 can be neatly folded along a fold line.

(5) Example of article provided with absorbent body Hereinafter, an example of an article provided with the absorbent body 40 folded as described above will be described. The absorbent body can be applied to absorbent articles such as disposable diapers and sanitary napkins. Below, the structure of the absorbent article provided with the absorber 40 is demonstrated with reference to FIG.14 and FIG.15. In addition, the same code | symbol is attached | subjected about the same structure as the structure of the absorber demonstrated in 1st Embodiment.

FIG. 14 is a plan view of an absorbent article provided with a folded absorbent body. FIG. 15 is a cross-sectional view of the absorbent article taken along the line 15A-15A in FIG.

The absorbent article 10 includes an absorbent body 40, a top sheet 20 disposed on the skin surface side of the absorbent body 40, and a back sheet 30 disposed on the non-skin surface side of the absorbent body 40. The absorber 40 is folded as described in the first to third embodiments.

The absorbent body 40 has high

basis weight regions

44a, 44b, 44c, a first low basis weight region 42a, and a second low basis weight region 42b. The ends of the outer high

basis weight regions

44 a and 44 c in the width direction W are placed on the central high basis weight region 44 b in the width direction W. The 1st low basic weight area | region 42a is located between the high basic weight area | region 44a and the high basic weight area | region 44b, and is connected with the high basic weight area |

regions

44a and 44b. The 2nd low basic weight area | region 42b is located between the high basic weight area | region 44b and the high basic weight area | region 44c, and is connected with the high basic weight area |

regions

44b and 44c.

According to such an absorbent article, the thickness of the central portion of the absorbent body in the width direction W is relatively thin. On the other hand, the region adjacent to the central portion of the absorbent body in the width direction W is a tatami mat region in which the high basis weight region 44b, the low

basis weight region

42a or 42b, and the high

basis weight region

44a or 44b overlap. Therefore, it becomes relatively thick. Therefore, since the center part of the absorber 40 in the width direction W is dented in the non-skin surface side, the space extended in a longitudinal direction between a wearer and the absorber 40 is formed. The body fluid can be diffused in the longitudinal direction by the space, and it becomes easy to effectively utilize the liquid absorption performance over the entire region of the absorbent body 40 in the longitudinal direction.

Moreover, the edge part of the absorber 40 in the width direction W becomes the high basic weight area |

regions

44a and 44c. Therefore, the edge part of the absorber 40 in the width direction W becomes thinner than the thickness of said tatami mat area. Therefore, the uncomfortable feeling around the wearer's leg can be reduced.

(6) Other Embodiments As described above, the present invention has been described in detail using the above-described embodiments. However, for those skilled in the art, the present invention is not limited to the embodiments described in the present specification. It is clear. The present invention can be implemented as modified and changed modes without departing from the spirit and scope of the present invention defined by the description of the scope of claims. Therefore, the description of the present specification is for illustrative purposes and does not have any limiting meaning to the present invention.

For example, in the above embodiment, during the folding method, the absorbent body 40 extends continuously in the longitudinal direction L and is not cut into lengths that are applied to individual articles in the longitudinal direction L. Instead of this, the absorbent body may be folded in a state of being divided into a predetermined length applied to a target product.

Moreover, in the said embodiment, the both

sides

40a and 40b of the absorber 40 are folded by Z shape by sectional view. Alternatively, both

side portions

40a and 40b of the absorber 40 may be folded back into a U shape in a cross-sectional view. In this case, the both

side portions

40a and 40b of the absorber 40 may be folded back during the folding step S3 without placing the both

side portions

40a and 40b of the absorber 40 on the

guide plates

140 and 142.

Furthermore, in the said embodiment, the both

sides

40a and 40b of the both

sides

40a and 40b of the absorber 40 are folded. Instead, only one

side

40a or 40b of the absorber 40 may be folded. In this case, only one of the first guide plate 140 and the second guide plate 142 may be used in the folding step S3.

40 Absorber 41 Absorbent material 42a First low basis weight region 42b Second low

basis weight region

44a, 44b, 44c High basis weight region 46 Core wrap 54 Adhesive 140 First guide plate 142 Second guide plates FL1a, FL1b, FL2a, FL2b Folding line S1 First pressing step S2 Application step S3 Folding step S4 First pressing step

Claims

A folding method that includes an absorbent material and folds the absorbent body while conveying the absorbent body having a longitudinal direction and a width direction orthogonal to the longitudinal direction, along the longitudinal direction,
The absorber is
A first low basis weight region extending in the longitudinal direction;
A pair of high basis weight regions adjacent to both sides of the first low basis weight region in the width direction,
The folding method includes a folding step of folding the absorbent body along a fold line along the first low basis weight region in a region between the pair of high basis weight regions.
When the region between the pair of high basis weight regions is equally divided into three in the width direction, and the region located at the center in the width direction of the region between the pair of high basis weight regions is defined as a central region, The folding method according to claim 1, wherein the folding line is located outside the central region.
The folding method according to claim 1 or 2, further comprising a first pressing step for pressing the absorber in a thickness direction before the folding step.
The folding method according to claim 3, wherein the thickness of the high basis weight region is larger than the thickness of the low basis weight region at least before the first pressing step.
The folding method according to any one of claims 1 to 4, further comprising a second pressing step for pressing the absorber in a thickness direction after the folding step.
The folding method according to any one of claims 1 to 5, wherein the first low basis weight region continuously extends in the longitudinal direction.
7. The method according to claim 1, further comprising an application step of applying an adhesive in a folding range that is hidden inside the absorber by folding the absorber along the fold line before the folding step. The folding method described in 1.
The folding method according to claim 7, wherein, in the application step, the adhesive is applied to the first low basis weight region.
The folding method according to claim 7 or 8, wherein, in the application step, the adhesive is applied to the absorbent body in a state where a coating machine for applying the adhesive is separated from the absorbent body.
The absorbent body has a cover sheet that wraps the absorbent material,
The folding method according to claim 1, wherein the cover sheet is bonded to the absorbent material with an adhesive.
The absorber is
A second low basis weight region extending in the longitudinal direction;
A pair of high basis weight regions adjacent to both sides of the second low basis weight region,
In the folding step, after the absorber is folded at the fold line along the first low basis weight region in a region between a pair of high basis weight regions adjacent to both sides of the first low basis weight region. The absorber is folded at a fold line along the second low basis weight region in a region between a pair of high basis weight regions adjacent to both sides of the second low basis weight region. The folding method according to any one of claims.
The absorber is
A second low basis weight region extending in the longitudinal direction;
A pair of high basis weight regions adjacent to both sides of the second low basis weight region,
In the folding step, when the absorber starts to be folded at the fold line along the first low basis weight region in a region between a pair of high basis weight regions adjacent to both sides of the first low basis weight region. At the same time or before finishing folding, the absorber is folded at a fold line along the second low basis weight region in a region between a pair of high basis weight regions adjacent to both sides of the second low basis weight region. The folding method according to any one of claims 1 to 10.