JP7010276B2 - Absorbent article manufacturing equipment - Google Patents

Description

The present invention relates to an apparatus and a method for producing an absorbent article.

Conventionally, absorbent articles such as disposable diapers and menstrual napkins have been known. The absorbent article is provided with an absorbent mat that absorbs liquids such as urine and menstrual blood excreted by the wearer. By increasing the liquid absorption property of this absorbent mat, the comfort of the wearer can be improved.
Therefore, an absorbent mat in which a powdery and granular highly water-absorbent resin is mixed with a fiber material such as pulp or rayon has been developed. In this absorbent mat, the liquid excreted from the wearer is diffused by the fiber material and absorbed by the highly water-absorbent resin, so that the liquid absorbency is enhanced (see Patent Document 1). Further, an absorption mat in which a groove-shaped pattern is press-molded has been proposed. In this absorbent mat, the movement and leakage of the liquid excreted from the wearer are suppressed by the groove-shaped pattern, and the liquid is surely absorbed by the absorbent mat, so that the liquid absorbency is improved.
(See Patent Document 2).

Japanese Unexamined Patent Publication No. 2008-284182 Japanese Unexamined Patent Publication No. 2004-298411

By the way, the highly water-absorbent resin mixed with the fiber material may be aggregated in the absorbent mat. When this agglomerate is sandwiched by press molding of a pattern on an absorbent mat, if it remains in the press area and is crushed, the crushed agglomerate promotes the integration of the fiber materials with each other and the absorbent mat. Restoration and curing are suppressed. On the other hand, if the agglomerates move in a direction away from the press region, the agglomerates do not remain in the pattern, and the feeling of foreign matter to the wearer and the hardening of the absorbent mat are suppressed.

However, the agglomerates in the outer edge region in the press region tend to remain in the outer edge region without being crushed because the press pressure is not sufficiently applied. If the agglomerates remain in the outer edge region without being crushed, the hardening of the pattern at the molded portion of the absorbent mat cannot be suppressed, and the comfort of the wearer may be reduced.

The manufacturing apparatus and manufacturing method for the absorbent article shown in this case were devised in view of the above-mentioned problems, and one of them is for the purpose of manufacturing the absorbent article for ensuring the comfort of the wearer. Not limited to this purpose, it is also possible to exert actions and effects derived from each configuration shown in the "mode for carrying out the invention" described later, which cannot be obtained by the conventional technique. It can be positioned as another purpose.

(1) In the absorbent article manufacturing apparatus disclosed here, an absorbent mat having a highly water-absorbent resin is sandwiched between a first roll and a second roll, and a pattern is pressed and molded.
In the manufacturing apparatus, the first convex portion projecting in a shape corresponding to the pattern on the outer periphery of the first roll and the first convex portion projecting in a shape corresponding to the pattern on the outer periphery of the second roll. A second convex portion that forms the pattern by sandwiching a part of the absorbent mat between the convex portion and pressing the pattern, and a first tip portion of the first convex portion and a second tip portion of the second convex portion. Each outer edge portion of the above is provided with an exclusion portion for removing the highly water-absorbent resin from the outer edge region where the absorption mat is pressed.

(2) The exclusion portion has an exclusion structure in which the highly water-absorbent resin is moved to a central region where the absorption mat is pressed at the central portions of the first tip portion and the second tip portion to be pulverized. It is preferable to have.
(3) The exclusion structure has a tip recess in which one of the first tip and the second tip is recessed, and the tip recess is the first tip and the second tip. On the other hand, it is preferable to have a pressed surface of the outer edge portion facing the central region.

(4) Further, it is preferable that the exclusion structure has a tip convex portion in which the other of the first tip portion and the second tip portion is projected.
(5) In the exclusion structure, it is preferable that the press direction dimension of the central region is larger than the press direction dimension of the outer edge region.

(6) Alternatively, it is preferable that the exclusion portion removes the highly water-absorbent resin by moving the highly water-absorbent resin in a direction away from the press region where the absorption mat is pressed at the first tip portion and the second tip portion. ..
(7) When the exclusion portion sandwiches a part of the absorption mat between the first convex portion and the second convex portion and presses the exclusion portion, the first peripheral speed of the first convex portion and the second convex portion are formed. It is preferable to give a peripheral speed difference by making it different from the second peripheral speed of.

(8) In this case, it is preferable that the exclusion portion is structurally provided. Specifically, the exclusion portion has the first convex portion and the second convex portion, and the first convex portion is formed in a shape in which the second convex portion is expanded or contracted in the circumferential direction. Is preferable.
That is, the first phase in which the first convex portion is provided in the first roll and the second phase in which the second convex portion is provided in the second roll are set in combination, and then the first roll is provided. It is preferable that the outer diameter of the second roll (corresponding to the radial position of the first convex portion) and the outer diameter of the second roll (corresponding to the radial position of the second convex portion) are provided differently.
If the rotation speeds of the first roll and the second roll are set to be equal, the first peripheral speed of the first convex portion and the second peripheral speed of the second convex portion are different. From this, the first convex portion and the second convex portion configured as described above have a configuration in which the first peripheral speed and the second peripheral speed are different from each other to give a peripheral speed difference, that is, the said. It constitutes an exclusion unit.

(9) Further, the exclusion portion differs between the first peripheral speed and the second peripheral speed when the first convex portion and the second convex portion sandwich and press a part of the absorption mat. It is preferable to have a control unit that gives a peripheral speed difference.
(10) The first tip portion and the second tip portion are preferably formed into a smoothly continuous surface shape.

(11) In the method for producing an absorbent article disclosed here, an absorbent mat having a highly water-absorbent resin is sandwiched between a first roll and a second roll, and a pattern is pressed to form the article.
In the present manufacturing method, a part of the absorbent mat is formed between the first convex portion and the second convex portion projecting in a shape corresponding to the pattern on the outer periphery of each of the first roll and the second roll. In the pressing step of sandwiching and pressing to form the pattern, and in the pressing step, the absorbent mat is formed at the outer edges of the first tip of the first convex portion and the second tip of the second convex portion. It has an exclusion step of removing the highly water-absorbent resin from the outer edge region to be pressed.

According to the manufacturing apparatus and manufacturing method for the absorbent article shown in the present case, the highly water-absorbent resin is less likely to remain in the outer edge region where the absorption mat is pressed at the outer edges of the first convex portion and the second convex portion. It is possible to suppress the hardening of the pattern forming portion in the absorbent mat. Therefore, it is possible to manufacture an absorbent article that ensures the comfort of the wearer.

It is a figure explaining the 1st Embodiment, and is the perspective view which shows the roll which presses and forms a pattern on the absorption mat. It is a figure explaining the 1st Embodiment, and is the enlarged sectional view which cut the convex part provided on the outer periphery of a roll in the radial direction along the circumferential direction at the press part. It is a figure explaining the 1st Embodiment, and is the flowchart which shows the manufacturing method of the absorbent article. It is a figure explaining the modification of the 1st Embodiment, (A) shows the 1st modification of a convex part, and (B) shows the 2nd modification of a convex part. It is a figure explaining the 2nd Embodiment, and is the perspective view which shows the roll which presses and forms a pattern on the absorption mat. It is a figure explaining the 2nd Embodiment, and is the enlarged sectional view which cut the convex part provided on the outer periphery of a roll in the radial direction along the circumferential direction at the press part.

With reference to the drawings, a manufacturing apparatus and a manufacturing method of an absorbent article as an embodiment will be described. It should be noted that the embodiments shown below are merely examples, and there is no intention of excluding the application of various modifications and techniques not specified in the following embodiments. Each configuration of the present embodiment can be variously modified and implemented without departing from the gist thereof. In addition, it can be selected as needed, or it can be combined as appropriate.

The absorbent article manufactured by the apparatus shown in the present embodiment is an auxiliary tool that is worn by the wearer and absorbs a liquid such as urine or menstrual blood. Examples of absorbent articles include tape-type and pants-type disposable diapers (so-called "disposable disposable diapers"), urine pads, menstrual napkins, panty liners, and the like. These absorbent articles are provided with an absorbent mat that absorbs the liquid excreted by the wearer.
In the present embodiment, an apparatus for forming a pattern by pressing the formed absorbent mat with a roll will be mainly described. The absorbent mat on which the pattern is formed is provided on the absorbent article through various steps such as encapsulation, bonding, and cutting.

For this device, the axial, radial and circumferential directions are determined based on the axis of the roll, and the upstream and downstream are determined based on the rotation direction of the roll. For the absorbent mat, the side facing the wearer's skin (inside when worn) is the skin side, and the opposite side of the skin side (outside when worn) is the non-skin side. The direction connecting the surface side and the non-skin surface side is the thickness direction, and the direction orthogonal to the transport direction and the thickness direction is the width direction. In addition, the direction of action of gravity is downward, and the opposite direction below is upward.

[I. First Embodiment]
[1. Absorption mat]
First, the absorption mat 4 provided on the absorbent article will be described with reference to FIG. In the absorption mat 4 illustrated in FIG. 1, the upper side is the skin surface side, the lower side is the non-skin surface side, and the vertical direction is the thickness direction.

The absorption mat 4 is a mat-like member that absorbs and holds a liquid. In this absorbent mat 4, a powder-granular superabsorbent polymer (so-called SAP <Superabsorbent polymer>, also referred to as a superabsorbent polymer or a superabsorbent polymer) is formed on crushed or defibrated pulp fiber (fiber material) 4a. 4b is mixed. For example, the absorbent mat 4 is formed by mixing and laminating the highly water-absorbent resin 4b with the dispersed pulp fibers 4a. In the absorbent mat 4 thus formed, the liquid diffused by the pulp fibers 4a is absorbed and held by the highly absorbent resin 4b.
In addition to or in addition to the pulp fiber 4a, a fibrous material such as rayon or cotton may be used.

Further, in the absorption mat 4, a part of the highly water-absorbent resin 4b is aggregated. The aggregated highly water-absorbent resin 4b has an outer size of, for example, about 400 μm or 600 μm and is mixed with the pulp fiber 4a.
Here, a strip-shaped absorbent mat 4 in which another sheet (top sheet) is laminated on the skin surface side after being wrapped with a wrap sheet will be described as an example.

The absorbent mat 4 wrapped with the wrap sheet is ensured to have a fixed shape, and the absorbent mat 4 on which another sheet is laminated is enhanced in tactile sensation and liquid absorption to the wearer. As the wrap sheet, a tissue or a non-woven fabric can be used. It is preferable to use tissue as a wrap sheet because tissue has better shape followability than non-woven fabric. As a sheet different from the wrap sheet, a woven fabric, a non-woven fabric, or a porous film can be used.
A groove-shaped pattern 3 is formed on the absorbent mat 4 by pressing (compression). Here, a pattern 3 in which a grid-like pattern formed on each of the skin surface side and the non-skin surface side is continuously recessed is illustrated.

[2. roll]
Next, a pair of rolls 10 and 20 formed by pressing the pattern 3 with the absorption mat 4 sandwiched between them will be described.
<Basic configuration>
First, the basic configurations of the rolls 10 and 20 will be described.
The pair of rolls 10 and 20 are press rolls that are parallel to each other and rotate about the axes C ₁ and C ₂ extending in the width direction.

Here, two rolls 10 and 20 are arranged one above the other. Specifically, the upper roll (first roll) 10 is arranged above the absorbent mat 4 to be conveyed, and the lower roll (second roll) 20 is arranged below. The absorption mat 4 to be conveyed below the upper roll 10 and above the lower roll 20 is sandwiched.

These rolls 10 and 20 rotate at a peripheral speed corresponding to the transport speed of the absorption mat 4. Specifically, the outer peripheral speed of the upper roll 10 (hereinafter referred to as "upper peripheral speed"<first peripheral speed>) and the outer peripheral speed of the lower roll 20 (hereinafter referred to as "lower peripheral speed"<second peripheral speed>) are , It is set to be equal to the transport speed of the absorption mat 4.
Here, the outer diameters of the rolls 10 and 20 are set to be equal, and the rotation speeds of the rolls 10 and 20 are also set to be equal.

An upper convex portion (first convex portion) 11 for forming a pattern 3 by pressing a part of the absorption mat 4 is provided on the outer periphery of the upper roll 10. The upper convex portion 11 is a press mold provided so as to project into a shape corresponding to the pattern 3 to be molded.
Similarly, a lower convex portion 21 (second convex portion) 21 for forming the pattern 3 by pressing a part of the absorption mat 4 is provided on the outer periphery of the lower roll 20. The lower convex portion 21 is provided so as to project into a shape corresponding to the pattern 3 to be molded.

That is, at the pressed portion, the upper convex portion 11 is located above the absorption mat 4, and the lower convex portion 21 is located below. A part of the absorption mat 4 sandwiched between the upper convex portion 11 and the lower convex portion 21 facing each other in this way is pressed in the thickness direction (here, the vertical direction). A pattern 3 is formed in this pressed portion.
As the convex portions 11 and 21, a metal press die (mold) or a rubber press die (rubber die) can be used. These convex portions 11 and 21 are provided on the outer circumferences of the corresponding rolls 10 and 20 over the entire circumference.

<Detailed configuration>
Further, a configuration for moving the highly water-absorbent resin in the region where the pattern 3 is formed will be described in detail with reference to FIG.
First, the region of the absorption mat 4 on which the pattern 3 is formed will be described.

The pattern 3 is formed in the press region D which is sandwiched between the tip portion (first tip portion) 12 of the upper convex portion 11 and the tip portion (second tip portion) 22 of the lower convex portion 21 and pressed in the absorption mat 4. Is molded. The press region D is roughly divided into two regions: a circumferential center C _P of the convex portions 11 and 21, a central region D ₁ of the peripheral edge thereof, and an outer edge region D ₂ of the peripheral edge of the central region D ₁ .
The central region D ₁ is a region pressed by the central portions 13 and 23 at the tip portions 12 and 22 of the convex portions 11 and 21. Further, the outer edge region D ₂ is a region pressed by the outer edge portions 14 and 24 at the tip portions 12 and 22 of the convex portions 11 and 21.

The "outer edge" in the present embodiment means a portion of the target object (here, "press area D" or "tip portions 21 and 22") along the outer side.
Specifically, the outer edge region D ₂ means a region (edge) along the outer side (here, each end portion upstream and downstream in the circumferential direction) of the press region D. The outer edge region D ₂ is a region different from the central region D ₁ of the press region D, and is a region located outside (peripheral) of the central region D ₁ .
Similarly, the outer edge portions 14 and 24 mean a region (edge) along the outer side (here, each end portion upstream and downstream in the circumferential direction) of the tip portions 12 and 22.

The manufacturing apparatus is provided with an exclusion structure (exclusion portion) 5 for eliminating the aggregated highly water-absorbent resin 4b from the outer edge region D ₂ . In the present embodiment, the exclusion structure 5 for removing the aggregated highly water-absorbent resin 4b from the outer edge region D ₂ by moving from the outer edge region D ₂ to the central region D ₁ is exemplified. The exclusion structure 5 is composed of convex portions 11 and 21.
Hereinafter, the convex portions 11 and 21 constituting the exclusion structure 5 will be described in detail.

The upper tip portion 12 of the upper convex portion 11 is provided with a further protruding tip convex portion 15. Further, the lower tip portion 22 of the lower convex portion 21 is provided with a recessed tip recess 25. In the tip recess 25, the press surface 24 a of the outer edge portion 24 is provided so as to face the central region D ₁ (inside).
Here, the tip convex portion 15 is formed in which the protrusion dimension of the upper tip portion 12 increases toward the circumferential center _CP of the upper convex portion 11. Similarly, a tip concave portion 25 is formed in which the protruding dimension of the lower tip portion 22 becomes smaller toward the circumferential center _CP of the lower convex portion 21. Each of the tip convex portion 15 and the tip concave portion 25 has an arcuate shape in a radial cross section along the circumferential direction.

Further, in the exclusion structure 5, focusing on the distance (this is referred to as “press direction dimension”) in which the upper convex portion 11 and the lower convex portion 21 are separated in the radial direction at the press portion, the press direction dimension of the outer edge region D ₂ is taken into consideration. The press direction dimension P ₁ in the central region D ₁ is set to be larger (P ₂ <P ₁ ) than P ₂ . In other words, the most protruding outer edge and the most at the lower tip of the lower convex portion 21 than the radial dimension L1 between the _most protruding center and the least protruding outer edge of the upper tip 12 of the upper convex portion 11. The radial dimension L ₂ with respect to the non-protruding center is larger (L ₁ <L ₂ ).
As described above, the tip portions 12 and 22 that are butted against each other in the exclusion structure 5 are provided with the tip recess 25 that is relatively deep with respect to the tip convex portion 15.

[3. flowchart]
Subsequently, a method for producing an absorbent article will be described with reference to FIG. This manufacturing method is a method of manufacturing an absorbent article by the above-mentioned manufacturing apparatus.
In this manufacturing method, each step is carried out in the order of the front step (step A10), the pressing step (step A20), and the back step (step A30). Further, in the pressing process, the exclusion step (step A22) is carried out.

In the pre-step of step A10, the absorbent mat 4 is formed by mixing and laminating the highly water-absorbent resin 4b with the dispersed pulp fibers 4a. Here, the formed absorbent mat 4 is covered with a wrap sheet, and another sheet is laminated.
In the pressing step of step A20, a part of the formed absorption mat 4 is pressed by the convex portions 11 and 21 of the rolls 10 and 20, and the pattern 3 is formed in the press region D.

At this time, in the elimination step of step A22, the aggregated highly water-absorbent resin 4b is moved by the exclusion structure 5 to be excluded from the outer edge region D ₂ . Here, the highly water-absorbent resin 4b aggregated by moving to the central region D ₁ is excluded from the outer edge region D ₂ . Then, the pattern 3 is formed in the press region D.
In the post-step of step A30, various steps such as encapsulation, bonding, and cutting are performed to provide the absorbent mat 4 on the absorbent article.

[4. Action and effect]
Since the apparatus and method for producing the absorbent article shown in the present embodiment are configured as described above, the following actions and effects can be obtained.
(1) The manufacturing apparatus is provided with an exclusion structure 5 for moving the highly water-absorbent resin 4b from the outer edge region D ₂ to the central region D ₁ . Therefore, the aggregated highly water _- absorbent resin 4b is less likely to remain in the outer edge region D2 where the press pressure is not sufficiently applied.

Moreover, since the press pressure is surely applied to the highly water-absorbent resin 4b excluded from the outer edge region D ₂ and moved to the central region D ₁ , even if the moved high water-absorbent resin 4b is aggregated, it is aggregated. This agglomerate can be reliably crushed. Therefore, it is possible to promote the integration of the pressed pulp fibers 4a. Restoration of the absorption mat 4 can be suppressed.
Further, since the aggregate of the highly water-absorbent resin 4b is less likely to remain in the outer edge region D ₂ and the press region D, it is possible to suppress the feeling of foreign matter to the wearer and the curing of the absorbent mat 4.
In this way, it is possible to manufacture an absorbent article that ensures the comfort of the wearer.

(2) In the exclusion structure 5, the absorption mat 4 in the press region D is _pressed not only in the press direction but also toward the center CP in the circumferential direction by the tip recess 25 in which the lower tip 22 is recessed in the lower convex portion 21. be able to. Therefore, the pattern 3 can be reliably formed on the absorption mat 4.
More specifically, in the tip recess 25, the press surface 24a of the outer edge 24 of the lower tip 22 faces the central region _D1 . Therefore, a component force from the applied press pressure toward the central region D ₁ can be applied to the highly water-absorbent resin 4b aggregated in the outer edge region D ₂ . Therefore, the aggregate of the highly water-absorbent resin 4b can be reliably moved from the outer edge region D ₂ to the central region D ₁ and pulverized.

(3) Further, the exclusion structure 5 is formed with a tip convex portion 15 in which the upper tip portion 12 is projected from the upper convex portion 11. Therefore, the absorption mat 4 is surely sandwiched between the tip convex portion 15 and the tip concave portion 25. Therefore, the absorbent mat 4 in the press region D can be reliably pressed, and the aggregated highly water-absorbent resin 4b can be reliably pulverized, and the pattern 3 can be reliably formed.

(4) Further, in the exclusion structure 5, the press direction dimension P ₁ of the central region D ₁ is larger than the press direction dimension P ₂ of the outer edge region D ₂ . Therefore, when the pattern 3 is press-formed, the absorption mat 4 is easily drawn from the outer edge region D ₂ toward the central region D ₁ . Therefore, by improving the mobility of the highly water-absorbent resin 4b from the outer edge region D ₂ to the central region D ₁ , the aggregated highly water-absorbent resin 4 b can be reliably removed from the outer edge region D ₂ and pulverized. ..
As for the method for producing an absorbent article, the same actions and effects as those described in (1) to (4) above can be obtained.

[I'. Modification example of the first embodiment]
Next, two modifications relating to the first embodiment will be described with reference to FIG. Except for the points described here, the configuration is the same as that of the first embodiment described above. The same reference numerals are given to these configurations, and the description of each part will be omitted.

The convex portions 11 ′, 11 ″, 21 ′, 21 ″ of the modified example described here have tip portions 12 ′, 12 ″, 22 ′, 22 ″ with respect to the convex portions 11 and 21 of the first embodiment described above. The shape of is different. Here, the shape of the radial cross section along the circumferential direction of the tip portions 12 ′, 12 ″, 22 ′, 22 ″ of the modified example is formed into a linear shape.
For example, as shown in FIG. 4 (A), the tip portions 12 ′ and 22 ′ of the convex portions 11 ′ and 21 ′ of the first modification have the protrusion dimension with respect to the rolls 10 ′ and 20 ′ centered in the circumferential direction C _P ′. Linearly increases or decreases toward.

The upper tip portion 12'of the upper convex portion 11'is a roof (gable-shaped roof) having both flows inward in the radial direction of the upper roll 10'from the circumferential center _CP'to the upstream and downstream respectively in the rotational direction. It is provided in a shape.
On the other hand, the lower tip portion 22'of the lower convex portion 21'is a roof (butterfly-shaped) having both flows toward the radial outer side of the lower roll 20'from the circumferential center _CP'to the upstream and downstream respectively in the rotational direction. It is installed like a roof).

Further, as shown in FIG. 4B, in the second modification, the upper convex portion 11 ″ is projected from the upper roll 10 ″ in a rectangular parallelepiped shape. In other words, the upper tip portion 12 ″ of the upper convex portion 11 ″ is provided with a flat top surface (flat roof shape). On the other hand, the lower convex portion 21 ″ projecting from the lower roll 20 ″ is formed in a shape in which a groove having a rectangular cross section is recessed from the rectangular parallelepiped top.

By forming the convex portions 11 ′, 11 ″, 21 ′, 21 ″ in this way, the same actions and effects as those of the first embodiment described above can be obtained. Moreover, by forming the cross-sectional shape of the tip portion 12', 12 ", 22', 22" into a linear shape, the formation cost of the convex portion 11', 11 ", 21', 21" can be reduced. Can be done.

[II. Second embodiment]
Next, a second embodiment will be described with reference to FIGS. 5 and 6. Except for the points described here, the configuration is the same as that of the first embodiment described above. The same reference numerals are given to these configurations, and the description of each part will be omitted.
[1. Constitution]
In the second embodiment, the apparatus and method for manufacturing the absorbent article move the highly water-absorbent resin 4b to the central region D ₁ and remove it from the outer edge region D ₂ , whereas the high water absorption resin 4b is removed from the outer edge region D 2. The difference is that the sex resin 40b is moved from the outer edge region D ₂₀ and removed from the press region D ₀ . Further, it is different in that a control unit 60 for controlling each rotation speed of the rolls 100 and 200 is provided. The pattern 30 formed on the absorption mat 40 extends linearly (straightly) in the width direction instead of in a grid pattern.

The exclusion unit 50 of the present embodiment gives (generates) a peripheral speed difference between the upper peripheral speed (first peripheral speed) of the upper roll 100 and the lower peripheral speed (second peripheral speed) of the lower roll 200. The exclusion unit 50 is composed of a control unit 60 in addition to the convex portions 110 and 210 of the rolls 100 and 200, and removes the highly water-absorbent resin 40b by moving it in a direction away from the press region D ₀ .
Hereinafter, the convex portions 110 and 210 of the rolls 100 and 200 will be described, and then the control unit 60 for controlling the rotation speed of the rolls 100 and 200 will be described.

<Convex part>
As shown in FIG. 5, the convex portions 110 and 210 are provided so as to project from the outer periphery of the rolls 100 and 200 in a shape corresponding to the pattern 30.
Since the pattern 30 of the present embodiment extends linearly in the width direction, the convex portions 110 and 210 for press-molding the pattern 30 are also provided so as to extend in the axial direction. Each of the rolls 100 and 200 here is provided with a plurality of convex portions 110 and 210 intermittently at intervals in the circumferential direction.

The phase in which the upper convex portion 110 is arranged in the circumferential direction on the outer periphery of the upper roll 100 and the phase in which the lower convex portion 210 is arranged in the circumferential direction on the outer periphery of the lower roll 200 are the same in the transport direction of the absorption mat 40. Is adjusted to be press molded. Specifically, the outer diameters of the upper roll 100 and the lower roll 200 are designed to be equal, and then the distance between the upper convex portions 110 and the distance between the lower convex portions 210 are designed to be equal.

As shown in FIG. 6, the tip portions 120 and 220 of the convex portions 110 and 210 of the rolls 100 and 200 are formed in shapes corresponding to each other.
Specifically, the upper tip portion (first tip portion) 120 is formed in a shape (one-sided roof shape) in which the protrusion dimension decreases toward the downstream in the rotation direction. On the contrary, the lower tip portion (second tip portion) 220 is formed in a shape in which the protrusion dimension increases toward the downstream in the rotation direction.
More specifically, when the convex portions 110 and 210 having the tip portions 120 and 220 press-mold the pattern 30, the top surface 121 of the upper tip portion 120 and the top surface 221 of the lower tip portion 220 are mutually formed. The shapes of the tips 120 and 220 are designed so as to be parallel.

<Control unit>
Subsequently, the control unit 60 will be described with reference to FIG.
The control unit 60 is a control unit that controls the rotation speeds of the rolls 100 and 200. Here, the control unit 60 is connected to the rolls 100 and 200 via a control line. However, the control unit 60 may be wirelessly connected to the rolls 100 and 200.
The control unit 60 makes the rotation speeds of the rolls 100 and 200 different when the convex portions 110 and 210 press-mold the pattern 30 with respect to the absorption mat 40.

Here, since the outer diameters of the rolls 100 and 200 are the same, the upper peripheral speed of the upper roll 100 and the lower peripheral speed of the lower roll 200 are made different by the control unit 60 at the time of press forming of the pattern 30.
Specifically, when the pattern 30 is press-formed, the lower peripheral speed is controlled to be faster than the upper peripheral speed. Further, except when the pattern 30 is press-formed, the lower peripheral speed is controlled to be lower than the upper peripheral speed, and the phases of the convex portions 110 and 210 are matched.

However, contrary to the peripheral speed control given in the specific example, the lower peripheral speed is controlled to be lower than the upper peripheral speed during press molding of the pattern 30, and the lower peripheral speed is controlled to be lower than the upper peripheral speed during press molding of the pattern 30. The lower peripheral speed may be controlled at a higher speed. In this case, in order to prevent the convex portions 110 and 210 from coming into contact with each other, it is possible to adopt a shape in which the tip portions 120 and 220 of the convex portions 110 and 210 are inverted with respect to the circumferential center _CP0 . preferable.

[2. Action and effect]
Since the present embodiment is configured as described above, the following actions and effects can be obtained in addition to the same actions and effects as those of the first embodiment.
(1) The exclusion unit 50 of the present embodiment moves the highly water-absorbent resin 40b in a direction away from the press region D ₀ to remove it. Therefore, the highly water-absorbent resin 40b aggregated in the outer edge region D ₂₀ where the press pressure is not sufficiently applied is less likely to remain. On the other hand, a sufficient press pressure is applied to the highly water-absorbent resin 40b aggregated in the central region D ₁₀ of the press region D ₀ . Therefore, the aggregate of the highly water-absorbent resin 40b in the central region D ₁₀ can be reliably pulverized. Therefore, the integration of the pulp fibers 40a can be promoted, and the restoration of the absorption mat 40 can be suppressed. Therefore, it is possible to suppress the feeling of foreign matter to the wearer and the hardening of the absorbent mat 40.
In this way, it is possible to manufacture an absorbent article that ensures the comfort of the wearer.

(2) Further, the exclusion unit 50 makes the upper peripheral speed of the upper roll 100 different from the lower peripheral speed of the lower roll 200 to give a peripheral speed difference. Therefore, the agglomerates of the highly water-absorbent resin 40b in the outer edge region D ₂₀ can be removed from the press region D ₀ by sliding out. Therefore, the aggregated highly water-absorbent resin 40b is surely removed from the outer edge region D ₂₀ , and the feeling of foreign matter to the wearer and the curing of the absorbent mat 40 can be sufficiently suppressed.

(3) Specifically, the upper peripheral speed of the upper roll 100 and the lower peripheral speed of the lower roll 200 are made different by the control unit 60 of the exclusion unit 50. Therefore, the aggregated highly water-absorbent resin 40b can be excluded from the outer edge region D ₂₀ only by adding the peripheral speed control of the rolls 100 and 200 to the existing manufacturing apparatus and manufacturing method. Therefore, it is possible to manufacture an absorbent article that ensures the comfort of the wearer while suppressing the device cost.

Further, the top surfaces 121 and 221 of the tip portions 120 and 220 are provided in a one-way roof shape parallel to each other. Therefore, when the pattern 30 is press-molded while giving a difference in peripheral speed between the rolls 100 and 200, it is possible to secure the area of the top surfaces 121 and 221 pressed against the absorption mat 30. Further, the aggregated highly water-absorbent resin 40b can be reliably rubbed out from the outer edge region D ₂₀ and removed.
As for the method for producing an absorbent article, the same actions and effects as those described in (1) to (3) above can be obtained.

[III. others]
Finally, other modifications of the present embodiment will be described.
For example, the rotation speed of the upper roll and the rotation speed of the lower roll may be set to be equal, and then the outer diameter of the upper roll and the outer diameter of the lower roll may be different. In this case, the lower convex portion is formed in a shape that is enlarged or reduced in the circumferential direction with respect to the upper convex portion according to the outer diameter ratio of the roll, and the lower convex portions are formed with respect to the distance between the upper convex portions. The interval between is also expanded or contracted in the circumferential direction. That is, the upper phase (first phase) in which the upper convex portion is provided in the upper roll and the lower phase (second phase) in which the lower convex portion is provided in the lower roll are set in combination. By forming the upper convex portion and the lower convex portion in this way, it is possible to form an exclusion portion that structurally gives a difference in peripheral speed by making the peripheral speeds of the rolls different without providing a control unit.

In addition, it is possible to secure a phase width or a period in which the absorption mat is sandwiched at least in a part between the upper convex portion and the lower convex portion. Therefore, the aggregate of the highly water-absorbent resin can be reliably removed from the outer edge region.
In addition to the structure in which the peripheral speeds of the rolls are different from each other as described above, a control unit for controlling the rotation speed of each roll may be provided in the exclusion unit. In this case, the difference in peripheral speed of the roll can be surely given, and the aggregate of the highly water-absorbent resin can be more surely removed from the outer edge region.

Further, the tip portion of the convex portion may be formed symmetrically with respect to the center in the circumferential direction, or the portion on the upstream side and the portion on the downstream side in the rotation direction of the roll may be formed asymmetrically. In this case, in the press forming of the pattern on the absorbent mat, the behavior of the initial stage (pressed) and the final stage (pressed out) can be optimized.
Further, the tip of the roll may be formed into a smoothly continuous surface shape. In this case, cutting of the absorbent mat during press molding of the pattern is suppressed. Therefore, it contributes to the improvement of shape retention and quality of the absorbent mat.
In addition, the pattern press-molded on the absorbent mat is not limited to the recesses of the linear lines extending continuously in the groove shape, and may be, for example, the recesses provided in a dot shape (intermittently).

10 Upper roll (first roll)
11 Upper convex part (first convex part)
12 Upper tip (first tip)
13 Central part 14 Outer edge part 15 Tip convex part 20 Lower roll (second roll)
21 Lower convex part (younger brother two convex part)
22 Lower tip (younger brother 2 tip)
23 Central part 24 Outer edge part 24a Press surface 25 Tip concave part 3 Pattern 4 Absorption mat 4a Pulp fiber 4b High water absorption resin 5 Exclusion structure (exclusion part)
C ₁ , C ₂ Axial center CP Circumferential center of convex portions 11 and 21 D Press area D ₁ Central area D ₂ Outer edge area _{P 1} Central area D ₁ Press direction dimension P ₂ Outer edge area D ₂ Press direction dimension L ₁ Radial dimension of upper tip 12 L ₂ Radial dimension of lower tip 22

Claims (4)

An absorbent article manufacturing device in which an absorbent mat having a highly water-absorbent resin is sandwiched between a first roll and a second roll and a pattern is pressed to form the article.
A first convex portion projecting from the outer periphery of the first roll into a shape corresponding to the pattern,
A second convex portion that is projected from the outer periphery of the second roll into a shape corresponding to the pattern, sandwiches a part of the absorption mat between the first convex portion and presses the mat, and forms the pattern.
An exclusion portion for removing the highly water-absorbent resin from the outer edge region where the absorption mat is pressed at each outer edge portion of the first tip portion of the first convex portion and the second tip portion of the second convex portion. Prepare ,
The exclusion portion has an exclusion structure in which the highly water-absorbent resin is moved to a central region where the absorption mat is pressed at the central portions of the first tip portion and the second tip portion to be pulverized.
The exclusion structure has a tip recess in which one of the first tip and the second tip is recessed.
The tip recess has a pressed surface of the outer edge facing the central region in one of the first tip and the second tip.
An apparatus for manufacturing an absorbent article . The apparatus for manufacturing an absorbent article according to claim 1 , wherein the exclusion structure has a tip convex portion in which the other of the first tip portion and the second tip portion is projected. The apparatus for manufacturing an absorbent article according to claim 1 or 2 , wherein in the exclusion structure, the press direction dimension of the central region is larger than the press direction dimension of the outer edge region . The apparatus for manufacturing an absorbent article according to any one of claims 1 to 3 , wherein the first tip portion and the second tip portion are formed into a smoothly continuous surface shape .

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