JP6359292B2 - Absorber manufacturing method - Google Patents

Description

  The present invention relates to a method for producing an absorbent body used for absorbent articles.

  A technique is known in which a narrow slit or groove is provided in an absorbent body used in an absorbent article such as a sanitary napkin, a panty liner, or a disposable diaper to improve various performances of the absorbent article. For example, Patent Document 1 describes an absorber in which a large number of through holes penetrating the back surface are formed on the absorber surface. The absorber surface is formed by disposing a hole forming roll having a large number of protrusions on the roll surface and an anvil roll having a recess at a position corresponding to the protrusions, and allowing the absorber to pass between both rolls. It is manufactured by forming a through-hole.

  In Patent Document 2, an elastic body that is fixed to the absorber side in the central region in the short direction of the product and applies a contracting force with respect to the arrangement direction, and an absorber in the vicinity of a region where the contracting action of the elastic body works. Absorbent products having slits formed are described. This slit uses a roller cutter provided with blades arranged parallel to each other on the outer periphery of the roller, or is provided with blades arranged non-parallel so as to approach and separate from each other on the outer periphery of the roller. It is formed by using a roller cutter.

JP 2002-035036 A JP 2004-105723 A

  As in the prior art described above, the present inventors use a slitting device having a cutter roll having a cutting blade on the peripheral surface and an anvil roll that receives the cutting blade of the cutter roll to push the slit into the absorber. It was found that when the width of the cutting blade is widened from the viewpoint of durability or the like, a compressed portion is easily formed around the slit. If such a compressed portion exists around the slit of the absorbent body, the rigidity around the slit increases, and the advantages of providing the slit in the absorbent body may not be fully exhibited.

  Therefore, the subject of this invention is providing the manufacturing method and manufacturing apparatus of an absorber which can eliminate the fault which the prior art mentioned above has.

  The present invention is a method of manufacturing an absorber having a slit by making a cut in the thickness direction of the absorber precursor while conveying the absorber precursor in one direction, The absorber precursor is sandwiched between a cutter roll having a cutting blade and an anvil roll that receives the cutting blade of the cutter roll, and the cutting blade is placed in the absorber precursor along the thickness direction of the absorber precursor. A slit forming step for forming a slit having a compressed portion around the absorber precursor and the absorber precursor having the slit formed thereon are wound around the winding portion of the bending processing means to be deformed. The manufacturing method of an absorber which comprises the softening process which softens the said pressing part by this is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the absorber which has a flexible slit can be manufactured efficiently.

Fig.1 (a) is a top view which shows the skin opposing surface side (surface sheet side) of the sanitary napkin as an example of the absorbent article provided with the absorber manufactured according to this invention, FIG.1 (b) FIG. 3 is an extraction plan view showing only the absorbent body of the sanitary napkin. 2 is a schematic cross-sectional view taken along the line II-II in FIG. FIG. 3 is a perspective view schematically showing an apparatus used for manufacturing the absorbent body shown in FIG. FIG. 4 is an enlarged cross-sectional view showing the main part of the cutter roll in the apparatus shown in FIG. FIG. 5 is a schematic view of the apparatus shown in FIG. 3 as viewed from the side. FIG. 6 is a schematic diagram (corresponding to FIG. 5) showing another apparatus used for manufacturing the absorbent body shown in FIG. Fig.7 (a) thru | or FIG.7 (d) is a schematic cross section of the auxiliary | assistant absorber which shows another example of how to fold an absorbent sheet. FIG. 8A to FIG. 8D are schematic views showing the arrangement of the winding portions of the bending means in the embodiment.

  The present invention will be described below based on preferred embodiments with reference to the drawings. First, the sanitary napkin which is an example of the absorbent article which has the absorber manufactured by this invention is demonstrated. As shown in FIGS. 1 and 2, the sanitary napkin 1 includes a liquid-retaining absorbent body 4, a surface sheet 2 disposed on the skin facing surface side of the absorbent body 4, and a non-skin facing surface of the absorbent body 4. It has an absorptive main body 5 having a back sheet 3 disposed on the side, and has a longitudinal direction X corresponding to the wearer's front-rear direction and a lateral direction Y orthogonal thereto.

  In addition, in this specification, a skin opposing surface is a surface which faces a wearer's skin side at the time of wear of an absorbent article in an absorbent article or its structural member (for example, absorbent main body 5), and is a non-skin opposing surface Is the surface of the absorbent article or its component that is directed to the side opposite to the skin side (clothing side) when the absorbent article is worn. Further, the longitudinal direction X coincides with the longitudinal direction of the absorbent article (absorbent body, absorbent body), and the lateral direction Y is perpendicular to the width direction (longitudinal direction) of the absorbent article (absorbent body, absorbent body). Direction).

The absorptive main body 5 is disposed on the abdomen (front side) of the wearer relative to the excretion part facing part B disposed opposite to the wearer's liquid excretion part (such as the vaginal opening) when worn and the excretion part facing part B when worn. The front portion A and the rear portion C arranged on the back side (rear side) of the wearer rather than the excretory portion facing portion B at the time of wearing are provided in the vertical direction X.
In addition to the absorbent main body 5, the napkin 1 further includes a pair of wing portions 7, 7 extending outward in the lateral direction Y from both side portions along the vertical direction X of the excretory portion facing portion B of the absorbent main body 5. have.

  As shown in FIG. 2, the top sheet 2 covers the entire skin facing surface of the absorbent body 4, and further extends outward in the lateral direction Y from both side edges along the longitudinal direction X of the absorbent body 4. On the other hand, the back sheet 3 covers the entire area of the non-skin facing surface of the absorbent body 4 and further extends outward in the lateral direction Y from both side edges along the longitudinal direction X of the absorbent body 4 to be described later. In addition, a side flap portion 6 is formed. The back sheet 3 and the side sheet 10 are joined to each other by known joining means such as an adhesive, heat seal, ultrasonic seal, and the like at the extended portions from both side edges along the longitudinal direction X of the absorber 4. The top sheet 2 and the back sheet 3 may be bonded to the absorber 4 with an adhesive.

  The absorbent body 4 has a laminated structure in which a main body absorbent sheet 401 and a central absorbent sheet 402 are laminated as shown in FIG. 2, and as shown in FIGS. B has a multilayer portion 42. As shown in FIG. 2, the multilayer part 42 is a part where the number of laminated absorbent sheets 401 and 402 constituting the absorbent body 4 is larger than the part located around the multilayered part 42. The multilayer part 42 in this embodiment is thicker than the part located in the circumference | surroundings, and forms the protruding part which protruded in the excretion part opposing part B to the surface sheet 2 side (skin opposing surface side of the napkin 1). Yes. The absorbent body 4 includes a main absorbent body 40 that forms the outer shape of the absorbent body 4, and an auxiliary absorbent body 41 that is smaller than the main absorbent body 40 that is arranged on a part of the main absorbent body 40. Yes. The auxiliary absorber 41 is located at least in the excretory part facing part B.

  The absorbent body 4 is preferably composed only of a laminated structure of absorbent sheets 401 and 402. The absorbent body 4 has a thin thickness, a high absorbent capacity, stability of folding processing, and freedom of shape deformation. From the point of view, it is preferable to use an absorbent sheet in which particles of a superabsorbent polymer are held between fiber layers.

  The main absorbent body 40 has a folded structure of a main body absorbent sheet 401 containing pulp. Specifically, the main absorbent body 40 is formed by folding the main body absorbent sheet 401 inwardly at positions of folding lines 401 a and 401 b extending along the vertical direction X. That is, the main body absorbent sheet 401 is folded at both ends. At this time, the positions of the folding lines 401a and 401b are adjusted so that the inwardly folded portions of the main body absorbent sheet 401 partially overlap each other. Therefore, the main absorbent body 40 has a laminated structure of two layers and three layers made of the main body absorbent sheet 401.

  On the other hand, the auxiliary absorbent body 41 has a folded structure of the central absorbent sheet 402 containing pulp. Specifically, the auxiliary absorbent body 41 folds the central absorbent sheet 402 inward along a fold line 402a extending along the longitudinal direction X at a portion located outward from the fold line 402a. Next, along the fold line 402b, the part located outward from the fold line 402b is folded inward toward the part that is folded first. The fold lines 402a and 402b are formed at positions that divide the length in the lateral direction Y of the central absorbent sheet 402 into approximately three equal parts. As a result, the central absorbent sheet 402 is in a folded state with three windings. Therefore, the auxiliary absorbent body 41 has a three-layer structure composed of the central absorbent sheet 402.

As shown in FIG. 2, the central absorbent sheet 402 that is in a folded state with three windings is disposed inside the main body absorbent sheet 401 that is in a folded state with both ends folded. That is, the main body absorbent sheet 401 and the central absorbent sheet 402 have a nested folding structure. As a result, in the laminated structure of the main body absorbent sheet 401 and the central absorbent sheet 402, it extends outward from at least a part of the peripheral edge of the central absorbent sheet 402, specifically from the entire region of the peripheral edge. A main body absorbent sheet 401 is laminated. In addition, since the auxiliary | assistant absorber 41 is located in the excretion part opposing part B as above-mentioned, the center absorbent sheet 402 which comprises this auxiliary | assistant absorber 41 is also located in the excretion part opposing part B. .
Each layer of the absorbent sheet laminated in five layers in the multilayer portion 42 and three layers in the portions other than the multilayer portion 42 is an “absorbent layer” in the present invention.

  The main absorbent body 40 having a folded structure of the main body absorbent sheet 401 has a substantially rectangular shape with rounded corners in plan view, and extends from the front part A to the rear part C via the excretory part facing part B. On the other hand, the auxiliary absorbent body 41 having a folded structure of the central absorbent sheet 402 has a substantially rectangular shape in plan view, and is arranged from the excretory part facing part B to the rear part C in the vicinity thereof. By arranging the auxiliary absorber 41 in a part of the main absorber 40, the absorption capacity of a part of the absorber 4 can be easily and efficiently increased. The auxiliary absorbent body 41 is laminated on the skin facing surface side of the main body absorbent sheet 401 constituting the main absorbent body 40, instead of being disposed inside the main absorbent body 40 composed of the folded main body absorbent sheet 401. Alternatively, it may be laminated on the non-skin facing surface side.

  On both sides along the vertical direction X of the skin facing surface of the absorbent main body 5 (skin facing surface of the topsheet 2), as shown in FIG. A pair of side sheets 10, 10 are arranged over substantially the entire length in the longitudinal direction X of the absorbent main body 5. The pair of side sheets 10 and 10 are each a linear first joining line 11 located in the excretory part facing part B, and the longitudinal direction X of the first joining line 11 (front part A and rear part C). It joins to the absorptive main body 5 (surface sheet 2) with the linear 2nd joining line 12 located in this. The first joining line 11 has a curved shape that protrudes outward in the lateral direction Y in plan view, and the second joining line 12 has a linear shape (zigzag line shape) that extends in the longitudinal direction in plan view. ). The side sheet 10 is made of a water-repellent nonwoven fabric. Thus, when the side sheet 10 is joined to the skin facing surface (surface sheet 2) of the absorbent main body 5 by the joining lines 11 and 12, as shown in FIG. A space P defined by the side sheet 10 and the top sheet 2 is formed inward in the direction Y. Since the space P is open toward the center in the lateral direction Y of the absorbent main body 5, excretion fluid such as menstrual blood flowing outward from the center in the lateral direction Y seems to be accommodated in the space P. As a result, the leakage of excretory fluid is effectively prevented.

  As shown in FIG. 1, the side flap portions 6 project greatly outward in the lateral direction Y at the excretory portion-facing portion B, whereby a pair of side flap portions 6 are provided on both the left and right sides along the longitudinal direction X of the absorbent main body 5. The wing portions 7, 7 are extended. Further, as shown in FIG. 1, the top sheet 2 and the back sheet 3 extend outward in the longitudinal direction X from the front end and the rear end in the longitudinal direction X of the absorbent body 4. The end seal portion is formed by bonding to each other by a known bonding means such as an agent, heat sealing, ultrasonic sealing or the like.

  The wing part 7 is used by being folded back to the non-skin facing surface side of the crotch part of clothes such as shorts. As shown in FIG. 1, the wing portion 7 has a substantially trapezoidal shape in which a lower base (a side longer than the upper base) is positioned on the side of the absorbent main body 5 in a plan view. On the non-skin facing surface of the wing part 7, a wing part adhesive part (not shown) for fixing the wing part 7 (napkin 1) to clothing (not shown) such as shorts is formed. The wing portion 7 that is folded back to the non-skin facing surface (outer surface) side of the crotch portion of the clothes can be adhered and fixed to the crotch portion by the adhesive portion. Moreover, the main body adhesion part (not shown) for fixing the absorptive main body 5 to clothes, such as shorts, is also formed in the non-skin opposing surface of the absorptive main body 5. In the napkin 1, the boundary line between the absorbent main body 5 and the wing portion 7 is a straight line (not shown) that connects the roots in the longitudinal direction X of the wing portion 7.

  As shown in FIG.1 and FIG.2, the surface sheet 2 and the absorber 4 are dented integrally on the skin opposing surface (skin opposing surface of the surface sheet 2) of the absorptive main body 5 toward the back surface sheet 3 side. The linear groove is formed so as to extend in the horizontal direction Y in the vertical groove 51 extending in the vertical direction X in the excretory part facing part B and in the front part A and the rear part C, respectively. The first and second lateral grooves 52 and 53 are formed. A linear groove | channel can be formed in accordance with a conventional method by embossing, such as a pressing process (what is called embossing) with or without heat (what is called embossing), or ultrasonic embossing. In the linear groove, the surface sheet 2 and the absorber 4 are not shown in the figure, but are bonded by an adhesive or integrated by thermal fusion or the like.

  As shown in FIG. 1, the absorbent body 4 is formed with a plurality of longitudinal slits 43 along the longitudinal direction X dispersed in the excretory part facing part B. The vertical slits 43 are formed in a state of being distributed in both the vertical direction X and the horizontal direction Y. As shown in FIG. 2, the vertical slit 43 is formed by cutting the absorber 4 in the thickness direction, and penetrates the laminated structure of the absorbent sheets 401 and 402 constituting the absorber 4. It is preferable. The vertical slits 43 are preferably not formed in the top sheet 2 and the back sheet 3 disposed above and below the absorber 4.

  Each vertical slit 43 is independent of each other, and a non-slit portion 43 ′ is located between adjacent vertical slits 43. Each vertical slit 43 is surrounded by a non-slit portion 43 ′ around the entire periphery.

  As described above, the vertical slit 43 is formed by cutting the absorber 4 in the thickness direction, and is formed from a cut having substantially no width, or preferably 1.5 mm. It has the following narrow space. When the vertical slit 43 has a width, the width means the length of the vertical slit 43 in a direction orthogonal to the direction in which the vertical slit 43 extends.

  The absorbent body 4 has a plurality of rear slits 45 extending in the rear part C located behind the excretory part facing part B so as to have a longitudinal direction in a direction intersecting with the longitudinal direction X of the napkin 1. As shown in FIG. 1B, the rear slit 45 is a plane in which the position of the central portion 45a in the longitudinal direction of the slit 45 is located on the front portion A side with respect to the positions of both end portions 45b and 45b in the longitudinal direction. It has a view shape, and more preferably has a plan view shape that is convexly curved toward the front portion A side. Moreover, the back slit 45 is formed in multiple numbers at intervals in the longitudinal direction X of the absorbent article.

FIG. 3 schematically shows an apparatus for manufacturing the absorbent body 4 in the sanitary napkin 1 described above. In a preferred embodiment of the present invention, as shown in FIG. 3, the absorbent body of the sanitary napkin 1 described above or the slit forming step using the cutting device 60 and the softening step using the softening means 70 are used. The continuous body 4 is manufactured.
The cutting device 60 used in the slit forming step includes a cutter roll 61 having cutting blades 63 and 64 on the peripheral surface, and an anvil roll 62 that receives the cutting blades 63 and 64 of the cutter roll 61. The cutting blades 63 are cutting blades for forming the vertical slits 43, and a plurality of cutting blades 63 are formed in the circumferential direction and the axial length direction of the cutter roll 61. The cutting blade 64 is a cutting blade for forming the rear slit 45, and a plurality of cutting blades 64 are formed at intervals in the circumferential direction of the cutter roll 61.

  The cutter roll 61 and the anvil roll 62 are arranged so that their axial centers 61 'and 62' are parallel to each other. A clearance is provided between the cutter roll 61 and the anvil roll 62, or both rolls are in contact with each other. The cutting blades 63 and 64 positioned on the peripheral surface of the cutter roll 61 are formed and arranged so as to coincide with the shape and arrangement of the slits 43 and 45 formed in the target absorbent body 4.

  An absorber precursor 4a (hereinafter also referred to as “precursor 4a” for the sake of simplicity), which is a precursor of an absorbent body having a laminated structure of a main body absorbent sheet and a central absorbent sheet, is shown by an arrow R in FIG. And is supplied between the cutter roll 61 and the anvil roll 62 in the cutting device 60. The state of the cross section in the thickness direction of the precursor 4a before being supplied between the two rolls 61 and 62 is shown in a circle indicated by I in FIG. In the precursor 4a before being supplied between the two rolls 61 and 62, the absorbent sheets 401 and 402 are not joined.

When the precursor 4a is supplied between both the rolls 61 and 62, the cutting blade 63 provided on the peripheral surface of the cutter roll 61 by the sandwiching pressure by the both rolls 61 and 62 extends along the thickness direction of the precursor 4a. Proceeds into the precursor 4a. Thereby, the vertical slit 43 and the back slit 45 are formed in the precursor 4a. The state of the cross section in the thickness direction of the precursor 4a after the vertical slit 43 is formed is shown in a circle indicated by II in FIG.
In the slit forming step, the respective absorbent sheets 401 and 402 are consolidated due to the progress of the cutting blade 63, so that the absorbent sheets 401 and 402 (absorption absorbed) stacked around the vertical slit 43. A pressure-bonding portion 43a (squeezed portion) between the layers is formed. Similarly, a crimping part 43a (pressing part) in which the laminated absorbent sheets 401 and 402 (absorbing layers) are crimped is also formed around the rear slit 45. "The slit which has a pressing part in the circumference | surroundings" may have the crimping | compression-bonding part 43a (squeezing part) only in one or both of a pair of slit adjoining part along the longitudinal direction of a slit, and it covers the perimeter of a slit. And may have a crimping part 43a (squeezing part).

  FIG. 4 is an enlarged cross-sectional view showing the tip of the cutting blade 63 provided on the cutter roll 61. The left-right direction of the paper surface in the figure coincides with the axial direction of the cutter roll 61. Moreover, the direction orthogonal to the paper surface in the figure is a direction parallel to the conveyance direction of the precursor 4a. As shown in the figure, the cutting blade 63 has its tip angle changed in two stages. Specifically, the cutting blade 63 forms a first tip angle θ1 by two hypotenuses L1, L1 at the most tip position. Further, the cutting blade 63 is at a position slightly closer to the base from the position of the most distal end (above the cutting blade 63 in FIG. 4) and forms a second distal end angle θ2 by the other oblique sides L2 and L2 connected to each oblique side L1. Yes. The first tip angle θ1 is larger than the second tip angle θ2. By changing the tip angle of the cutting blade 63 in two steps and making the first tip angle θ1 larger than the second tip angle θ2, wear of the cutting blade 63 is suppressed while forming a narrow slit. There is an advantageous effect that it is possible.

From the viewpoint of making the above advantageous effects more remarkable, the first tip angle θ1 is preferably 40 degrees or more, particularly 60 degrees or more, and preferably 100 degrees or less, particularly 90 degrees or less. For example, the first tip angle θ1 is preferably not less than 40 degrees and not more than 100 degrees, particularly preferably not less than 60 degrees and not more than 90 degrees. On the other hand, on the condition that the second tip angle θ2 is smaller than the first tip angle θ1, it is preferably 30 degrees or more, particularly 50 degrees or more, and preferably 90 degrees or less, particularly 70 degrees or less. . For example, the second tip angle θ2 is preferably not less than 30 degrees and not more than 90 degrees, particularly preferably not less than 50 degrees and not more than 70 degrees.
When the first tip angle θ1 is larger than the second tip angle θ2, a crimping portion 43a (squeezing portion) is more likely to be generated around the slits 43 and 45.

  If the crimping part 43a (squeezing part) is present around the vertical slit 43 and the rear slit 45, there is a possibility that the advantage of providing the slit on the absorber is not sufficiently exhibited. For example, although it is a slit provided for the wearer to improve the fit to the body shape, the flexibility of the absorber cannot be sufficiently increased, and the effect of improving the fit cannot be sufficiently obtained Even though the slit is provided to improve the followability to the wearer's movement, the followability to the wearer's movement may not be sufficiently improved.

  Therefore, in this embodiment, as described below, after the slit forming step, a softening step for softening the compressed portion is performed.

  In the softening process according to the present embodiment, the absorber precursor 4 ′ in which the slits 43 and 45 are formed in the slit forming process (hereinafter, also referred to as “precursor with slit 4 ′” for the sake of simplicity). The softening process is performed using the softening means 70 including one roll 71 (winding portion). The 1st roll 71 is a winding part which can wind the precursor 4 'with a slit.

As shown in FIGS. 3 and 5, the softening means 70 in the present embodiment includes, in addition to the first roll 71, a second roll 72 disposed on the upstream side in the conveying direction of the precursor 4 ′ with slit. And a third roll 73 disposed on the downstream side in the transport direction. The 1st-3rd rolls 71-73 are arrange | positioned so that those axial centers 71 ', 72', and 73 'may become mutually parallel. Further, a clearance is provided between the first roll 71 and the second roll 72, and a clearance is also provided between the second roll 72 and the third roll 73. Each of the first to third rolls is a flat roll having a flat surface.
The first roll 71 is disposed so that a part of the first roll 71 enters the space between the second roll 72 and the third roll 73, and more specifically, the lower half of the roll 71. Has entered.
In addition, as a winding part in this invention, the part etc. which the belt | belt conveyor bent by the roll and deform | transformed into circular arc shape other than a roll are mentioned.

The slitted precursor 4 ′ to be softened by the softening means 70 is transported by a known transport means (not shown) such as a belt conveyor, and as shown in FIG. After being introduced onto the circumferential surface of the first roll 71 and then onto the circumferential surface of the third roll 73, the circumferential surface of the third roll 73. Then, it is transferred to a known conveying means (not shown) such as a belt conveyor and further conveyed downstream.
As shown in FIG. 5, the slit-attached precursor 4 ′ is deformed into a circular arc shape that is convex toward the first surface “a” on the peripheral surface of the second roll 72. On the peripheral surface, it is deformed into a circular arc shape that is convex toward the second surface b side, and further, on the peripheral surface of the third roll 73, it is formed into a circular arc shape that is convex toward the second surface b side. Deformed. The precursor 4 ′ with slit passes through the first to third rolls 71 to 73 while being deformed into a shape along the peripheral surfaces of the first to third rolls 71 to 73. The first to third rolls 71 to 73 themselves may be drive rolls provided with drive means (not shown) such as a servo motor, or may be free rolls that do not have drive. good. In this case, a drive roll (not shown) is provided in the immediate vicinity of the downstream side of the third roll 73 so that the transportability of the slitted precursor 4 ′ is not impaired by the winding by the first to third rolls 71 to 73. Is preferably provided. In FIG. 3, in the circle indicated by III, the state of the cross section in the thickness direction of the absorbent body 4 after the flexible processing by the first to third rolls 71 to 73 is represented.
4 'with precursor slits, a second roll 72, it is conveyed while being brought successively deformed into a shape along the circumferential surface of the first roll 7 1 and the third roll 73, the crimping portion 43 a, The absorbent sheets 401 and 402 (absorbing layers) that have been joined so far are peeled off and separated, and the absorbent sheets 401 and 402 return to the non-joined state before the slit is formed.

  Thereby, the continuous body 4 of the target absorber with which the crimping | compression-bonding part 43a (pressing part) formed in the circumference | surroundings of the slits 43 and 45 softened is obtained successfully. The continuous body 4 of the absorbent body is cut to the size of the absorbent body of the individual absorbent article by a known cutting means to become the absorbent body 4 having the dimensions of the absorbent body of the sanitary napkin 1 described above.

In the precursor 4 ′ with slit, the first surface a is a surface located on the cutter roll 61 side during slit formation, and the second surface b is a surface located on the anvil roll 62 side during slit formation. is there.
The winding portion of the bending means used in the present invention may be such that, as with the first roll 71, the precursor 4 ′ with slit is curved toward the first surface a side, and the second and second 3, the slit precursor 4 ′ may be curved to the second surface b side, but the bending means used in the present invention is the slit precursor 4 ′. It is preferable to include both a roll (winding portion) that is bent toward the first surface a side and a roll (winding portion) that is bent toward the second surface b side, and the bending processing means 70 used in this embodiment. As above, a total of three rolls, that is, two rolls (winding portions) that bend the precursor 4 ′ with slits to the one surface a side and one roll (winding portion) that bends to the other surface b side. More preferably, the above rolls are provided.

  In the present embodiment, as shown in FIG. 5, in the portion delivered from the second roll 72 to the first roll 71, the precursor 4 ′ with slit has a cross-sectional shape along the transport direction R. Even in a portion that is bent so as to form an S shape and is transferred from the first roll 71 to the third roll 73, the cross-sectional shape of the precursor 4 ′ with slits along the transport direction R is S. It is bent to form a letter shape. The slit precursor 4 ′ is preferably bent so that a length of 100 cm or less in the conveying direction forms an S shape in a portion that is transferred from roll to roll. Note that the S-shape referred to in this specification includes an inverted S-shape in which left and right are reversed.

Of the first to third rolls 71 to 73, the holding angle θ11 of the first roll 71 having the largest holding angle of the precursor 4 ′ with slit is preferably 10 degrees or more, more preferably 40 degrees or more. Also, it is preferably 180 degrees or less, more preferably 90 degrees or less, and preferably 10 degrees or more and 180 degrees or less, more preferably 40 degrees or more and 90 degrees or less.
The holding angle of the precursor 4 ′ with slit in the first roll 71 is the cross section obtained by cutting the first roll 71 and the precursor 4 ′ with slit in a plane orthogonal to the axis 71 ′ of the roll. When the uppermost stream in the region where 'is in contact with the first roll 71 is the first contact P (not shown) and the most downstream in the region is the second contact P' (not shown), An angle formed by a straight line (line segment) connecting the axis 71 ′ and a straight line (line segment) connecting the second contact P ′ and the axis 71 ′. Similarly, with respect to the holding angle of the precursor 4 ′ with slit in the second roll 72 and the third roll 73, a straight line (line segment) connecting the first contact P and the axis 72 ′ or the axis 73 ′, The angle formed by the two tangent lines P ′ and a straight line (line segment) connecting the axis 72 ′ or the axis 73 ′.
The radius of the first roll 71 is preferably 10 mm or more, more preferably 15 mm or more, preferably 50 mm or less, more preferably 20 mm or less, and preferably 10 mm or more and 50 mm or less, more preferably It is 15 mm or more and 20 mm or less.

Each of the second roll 72 and the third roll 73 has a holding angle θ12, θ13 of the precursor 4 ′ with a slit of preferably 10 degrees or more, more preferably 20 degrees or more, and preferably 180 degrees. Hereinafter, it is more preferably 45 degrees or less, preferably 10 degrees or more and 180 degrees or less, more preferably 20 degrees or more and 45 degrees or less.
The radius of each of the second roll 72 and the third roll 73 is preferably 10 mm or more, more preferably 15 mm or more, and preferably 50 mm or less, more preferably 20 mm or less. Preferably they are 10 mm or more and 50 mm or less, More preferably, they are 15 mm or more and 20 mm or less.

Moreover, the 1st-3rd rolls 71-73 are the viewpoints of the softening of the pressing part of the periphery of the slit 43, and the radius of at least 1 roll is the slit 43 in the conveyance direction of precursor 4 'with a slit. Preferably, the radius of two or more rolls is preferably 4 times or less of the length of the slit 43, and the radius of all the rolls is less than 4 times the length of the slit 43. The length is preferably 4 times or less of the length.
The length of the slit here is the total length in the longitudinal direction of the slit when the slit is formed in parallel with the transport direction like the slit 43 shown in FIG. 3, and the slit is parallel to the transport direction. If it is not formed, the length in the conveyance direction between the front edge and the rear edge of the slit in the conveyance direction is set.

The slit to be softened in the softening step has a length in the transport direction defined as described above of preferably 2 mm or more, more preferably 5 mm or more, and preferably 100 mm or less, more preferably 50 mm or less, Further, it is preferably 2 mm or more and 100 mm or less, more preferably 5 mm or more and 50 mm or less.
Note that the radius of curvature when the winding portion is a cylindrical roll is the same as the radius of the roll.

On the other hand, when the winding portion is not a roll, for example, when the winding portion is a portion of the belt conveyor that is bent by the roll and deformed into a cross-section arc shape, the belt deformed into the cross-section arc shape. It is preferable that the curvature radius of is 4 times or less the length in the conveyance direction of the precursor 4 ′ with slit.
Moreover, the softening process in the present invention can provide a further excellent softening effect for the slits formed in a straight line extending in the transport direction.

FIG. 6 is a diagram showing another embodiment of the present invention.
In the embodiment shown in FIG. 6, the cutter roll 81 having the cutting blade 83 is formed after the slit precursor 4 ′ is formed from the absorber precursor 4 </ b> A using the cutting device 60 having the same configuration as the cutting device 60 described above. And an anvil roll 82 that receives the cutter blade 83 of the cutter roll, the slit-cured precursor 4 'is cut into the size of each absorber 4 and the single-wafer slit-cured precursor 4 is cut. The first bend processing means 70A provided with a transfer roll 75 (winding portion) provided with a suction hole on the outer peripheral surface thereof is used for the single-wafer slit precursor 4 ′. We are conducting a softening process. In the rotational direction, the transfer roll 75 is separated from the outer peripheral surface in a range P3 from a position in front of the receiving portion P1 of the sheet precursor 4 ′ with slit to a position exceeding the delivery portion P2 to the belt conveyor 79. Suction is possible. In the above-mentioned range P3, the sheet-shaped slit precursor 4 ′ is deformed into a shape along the peripheral surface of the transfer roll 75 while performing suction from the outer peripheral surface. Also with the precursor 4 ′, it is possible to efficiently soften the pressure-bonding portion 43a (squeezing portion) around the slit while preventing the precursor 4 ′ with slit from lifting from the outer peripheral surface of the roll.

In the embodiment shown in FIG. 6, after the first softening step using the transfer roll 75, the continuous sheet 76 having a strip shape is joined to the sheet-formed precursor 4 ′, and then the continuous sheet 76. A second softening process is performed using the second bending means 70B on the laminated body 77 composed of the sheet-shaped precursor 4 ′ with slits intermittently arranged on one side of the continuous sheet 76. ing.
The second bending means 70B has the same configuration as the bending means 70 described above, except that the first roll 71A includes a suction mechanism.
A plurality of suction holes are opened on the peripheral surface of the first roll 71A, and portions other than the opening are flat. The first roll 71A has an intake passage that communicates the opening on the circumferential surface with the opening provided on the side surface, and the opening provided on the side surface and an arcuate suction device disposed opposite to the side surface While the two are overlapped, suction from the peripheral surface is performed.
Also in the second softening step by the second bending means 70B, the laminated body 77 is shaped along the peripheral surface of the first roll 71A while performing suction from the peripheral surface of the first roll 71A. By deforming to the above, it is possible to efficiently soften the pressure-bonding portion 43a (pressing portion) around the slit in the single-sheet precursor 4 ′ with slit included in the laminate 77.
In the state of being laminated with the belt-like continuous sheet 77, the slitting precursor 4 ′ is subjected to the softening step by the front end and the rear end in the conveying direction R of the sheet precursor 4 ′ with slits, and the cutting blade 64. The attached rear slit 45 has an advantage of suppressing processing defects such as phase shift, bending, and kinking due to being caught by the second bending processing means 70B. The suction range P4 of the first roll 71A is the same as the contact range of the precursor 4 ′ with slit, and it is possible to suck and hold only while the laminated body 77 is bent on the first roll 71A. This is preferable from the viewpoint of preventing the attached precursor 4 'from being lifted.
Moreover, as the strip | belt-shaped continuous sheet 76, the sheet | seat which has air permeability is preferable, For example, the strip | belt-shaped original fabric of the surface sheet which consists of a nonwoven fabric which has air permeability can be used.

  The material for forming each part of the napkin 1 according to the above embodiment will be described. As the top sheet 2 and the back sheet 3, various kinds of materials conventionally used in the technical field can be used without any particular limitation. As the surface sheet 2, for example, liquid permeable sheets such as various nonwoven fabrics and perforated films subjected to a hydrophilic treatment can be used. Moreover, as the back sheet 3, a liquid-impermeable material or a water-repellent material can be used. As the liquid-impermeable material, a resin film, a resin film having fine pores and moisture permeability, a laminate material of a resin film and a nonwoven fabric, and the like can be used. A composite nonwoven fabric having a multilayer structure composed of bond, meltblown, spunbond, or the like, a spunbond nonwoven fabric, a heat bond nonwoven fabric, an air-through nonwoven fabric, or the like can be used.

As the absorbent sheets 401 and 402 constituting the absorbent body 4, a superabsorbent polymer is sprayed on wet paper or nonwoven fabric, and the paper or nonwoven fabric is superimposed thereon, and then dried and integrated. Can be used.
As such an absorptive sheet, for example, an absorptive sheet described in JP-A-8-246395 can also be used.
This absorbent sheet can be cut into a predetermined shape and used as a sheet-like absorber. The thickness per absorbent sheet is preferably 0.1 mm or more, particularly 0.3 mm or more, and preferably 2 mm or less, particularly 1.5 mm or less. More specifically, it is preferably 0.1 mm or more and 2 mm or less, particularly preferably 0.3 mm or more and 1.5 mm or less.

  As mentioned above, although this invention was demonstrated based on the preferable embodiment, this invention is not restrict | limited to the said embodiment. For example, the napkin 1 may not have the wing part 7. Moreover, you may have a back flap part which spreads and fixes to the inner surface of shorts in the both sides in the back part of the absorptive main body 5. FIG. Further, only the longitudinal slit 43 may be formed in the absorber without forming the rear slit 45. Moreover, in the manufacturing method of the absorber shown in FIG. 6, the 1st softening process using the transfer roll 75 may be abbreviate | omitted, the lamination | stacking of a strip | belt-shaped continuous sheet using the 2nd bending process means 71A, The second softening step may be omitted. Instead of the vertical slit parallel to the transport direction, a slit inclined with respect to both the transport direction and the direction perpendicular thereto may be formed. Moreover, the absorber manufactured does not have the multilayer part 42, but the lamination | stacking number of an absorbent sheet may be the same over the whole region. Further, the number of laminated absorbent sheets in the multilayer portion 42 in the case where the multilayer portion 42 is provided is not limited to the number shown in FIG. 2, and the difference in the number of laminated absorbent sheets between the multilayer portion 42 and other portions is also illustrated. It is not limited to the number shown in 2.

In the embodiment described above, the main body absorbent sheet 401 and the central absorbent sheet 402 constituting the absorbent body 4 are each folded to form a laminated structure composed of a plurality of layers. A laminate of a plurality of absorbent sheets may be used. Also, the absorbent sheet can be folded in various ways. For example, the auxiliary absorbent body 41 is formed by folding the central absorbent sheet 402 as shown in FIGS. 8 (a) to 8 (d). It may be folded.
The absorbent body to be manufactured in the present invention is not limited to such a form, and may be another form, for example, a pile pile of pulp fibers and a water-absorbing polymer. In this case, by passing through the first and / or second softening step, the pulp fibers in the crimping portion 43 are peeled apart and separated, and the distance between the pulp fibers is widened to obtain the effect of softening. .

  Moreover, although the said embodiment is an example which applied this invention to manufacture of the absorber of a sanitary napkin, this invention absorbs absorbers, such as a disposable diaper, an incontinence pad, a panty liner, etc. of other absorbent articles. The same applies to the manufacture of the body.

This invention discloses the manufacturing method and manufacturing apparatus of the following absorber further regarding embodiment mentioned above.
<1>
While conveying the absorber precursor in one direction, making a cut in the thickness direction of the absorber precursor, and manufacturing a absorber having a slit,
The absorber precursor is sandwiched between a cutter roll having a cutting blade on the peripheral surface and an anvil roll that receives the cutting blade of the cutter roll, and the absorber is cut along the thickness direction of the absorber precursor. A slit forming step of forming a slit having a pressure-bonding portion around the absorber precursor by proceeding into the precursor;
The manufacturing method of an absorber which comprises the softening process which softens the said crimping | compression-bonding part by winding the absorber precursor in which the said slit was formed around the winding part of a bending process means, and making it deform | transform.
<2>
The absorber has a laminated structure having a plurality of absorption layers,
In the slit forming step, as the pressure-bonding portion, a pressure-bonding portion in which a plurality of absorption layers are pressure-bonded is formed. In the softening step, at least one absorption layer in the pressure-bonding portion is separated, and the pressure-bonding portion. The manufacturing method of the absorber as described in <1> which softens.
<3>
The bending means includes at least one roll as the winding portion, and the holding angle of the absorber precursor in which the slit is formed is 10 degrees or more and 180 degrees or less. The manufacturing method of the absorber as described in <1> or <2>.
<4>
The winding portion has a plurality of suction holes on the surface, and deforms the absorber precursor having the slit formed on the surface while being held by suction. <1> to <3> The manufacturing method of the absorber of description.
<5>
<1> to <4>, wherein the bending means includes a plurality of the winding portions and bends the absorber precursor in which the slit is formed into an S-shaped cross section. Manufacturing method of absorber.
<6>
The absorber precursor or the absorber has a multilayer portion at a portion disposed in the excretory portion facing portion of the absorbent article, and the multilayer portion is the number of laminated absorbent sheets constituting the absorber. Is a part larger than the part located in the circumference | surroundings, The manufacturing method of the absorber in any one of <1>-<5>.
<7>
The multilayer portion is thicker than the portion located around it, and forms a raised portion that protrudes toward the topsheet side of the absorbent article at a portion disposed in the excretory part facing portion of the absorbent article. The manufacturing method of the absorber as described in <6>.
<8>
The said absorber is a manufacturing method of the absorber in any one of <1>-<7> comprised only from the laminated structure of the absorbent sheet.
<9>
The absorber precursor or the absorber is composed of an absorbent sheet having a single layer or a multilayer structure, and the absorbent sheet sprays a superabsorbent polymer on wet paper or non-woven fabric, on which paper The manufacturing method of the absorber as described in any one of <1>-<8> which is what integrated after drying and integrating a nonwoven fabric.
<10>
The said slit is a manufacturing method of the absorber in any one of <1>-<9> formed in the linear form extended in the conveyance direction of the said absorber precursor.
<11>
In the absorbent body precursor or the absorbent body, a plurality of longitudinal slits along the longitudinal direction X of the absorbent article are formed in a dispersed state at a portion disposed in the excretory part facing portion of the absorbent article. <1>-<10> The manufacturing method of the absorber as described in any one of <10>.
<12>
In the absorbent body precursor or the absorbent body, longitudinal slits along the longitudinal direction X of the absorbent article are formed in a state dispersed in both the longitudinal direction X and the transverse direction Y of the absorbent article, <1> to <10 The manufacturing method of the absorber of any one of>.
<13>
A longitudinal slit along the longitudinal direction X of the absorbent article is formed by cutting the absorber precursor in the thickness direction, and the longitudinal slit penetrates the laminated structure of the absorbent sheet constituting the absorber. The manufacturing method of the absorber as described in any one of <1>-<12>.
<14>
A plurality of longitudinal slits along the longitudinal direction X of the absorbent article are formed in the absorber precursor or the absorber, each longitudinal slit is individually independent, and between adjacent longitudinal slits The non-slit part is located, The vertical slit is the manufacturing method of the absorber as described in any one of <1> to <13>, in which the entire periphery is surrounded by the non-slit part.
<15>
The absorbent body has a plurality of rear slits extending in the rear part located behind the excretory part facing part of the absorbent article so as to have a longitudinal direction in a direction intersecting the longitudinal direction of the absorbent article. The manufacturing method of the absorber as described in any one of>-<13>.
<16>
The rear slit has a shape in plan view in which the position of the central portion in the longitudinal direction of the slit is located closer to the front portion side of the absorbent article than the positions of both end portions in the longitudinal direction, preferably the front portion side The manufacturing method of the absorber as described in <15> which has the shape of planar view curved convex toward the surface.
<17>
The said back slit is a manufacturing method of the absorber as described in <15> or <16> currently formed in multiple numbers at intervals in the longitudinal direction X of an absorbent article.
<18>
The cutting blade has a first tip angle θ1 formed by two hypotenuses L1, L1 at the most tip position, and is connected to each hypotenuse L1 at a position slightly closer to the base from the tip end position. The first tip angle θ2 is formed by the oblique sides L2 and L2, and the first tip angle θ1 is larger than the second tip angle θ2, according to any one of <1> to <16>. Method for manufacturing the absorber.
<19>
The first tip angle θ1 is preferably 40 ° or more, particularly preferably 60 ° or more, and is preferably 100 ° or less, particularly preferably 90 ° or less, and the first tip angle θ1 is 40 ° or more and 100 ° or less, The method for producing an absorbent body according to any one of <18>, in particular, preferably from 60 degrees to 90 degrees.
<20>
The second tip angle θ2 is preferably 30 ° or more, particularly 50 ° or more, preferably 90 ° or less, particularly preferably 70 ° or less, provided that the second tip angle θ2 is smaller than the first tip angle θ1. The method for producing an absorbent body according to <18> or <19>, wherein the second tip angle θ2 is preferably 30 degrees or more and 90 degrees or less, particularly preferably 50 degrees or more and 70 degrees or less.
<21>
In the precursor with slit, which is the absorber precursor forming the slit, the surface located on the cutter roll side at the time of slit formation is the first surface a, and the surface located on the anvil roll side at the time of slit formation is the second. When it is set as surface b,
The bending means includes, as the winding portion, a roll that curves the precursor with slit to the first surface a side, or a roll that curves the second surface b side, Or the manufacturing method of the absorber of any one of <1>-<20> provided with both the roll curved to the 1st surface a side, and the roll curved to the 2nd surface b side.
<22>
In the precursor with slit, which is the absorber precursor forming the slit, the surface located on the cutter roll side at the time of slit formation is the first surface a, and the surface located on the anvil roll side at the time of slit formation is the second. When it is set as surface b,
The bending processing means, as the winding part, causes the precursor with a slit to bend to one surface side of the first surface a and the second surface b and to bend to the other surface side 1 The manufacturing method of the absorber as described in any one of <1>-<21> provided with a total of three or more rolls of one roll.

<23>
The said slit is a manufacturing method of the absorber in any one of <1>-<22> whose length in the conveyance direction of the said absorber precursor is 2 mm or more and 100 mm or less.
<24>
The curvature radius of the said winding part is a manufacturing method of the absorber in any one of <1>-<23> which is 4 times or less of the length in the conveyance direction of the said absorber precursor of the said slit.
<25>
The absorber according to any one of <1> to <24>, wherein an inter-axis distance of each roll of the winding portion is not more than four times the length of the slit in the transport direction of the absorber precursor. Manufacturing method.

<26>
The said absorber is a manufacturing method of the absorber of any one of <1>-<25> which is an absorber of an absorbent article.
<27>
The absorbent article according to <26>, wherein the absorbent article is a sanitary napkin, a disposable diaper, an incontinence pad, or a panty liner.
<28>
In the said slit formation process, the said slit is not formed in the surface sheet and back surface sheet of an absorbent article which are distribute | arranged above and below the said absorber, The manufacturing method of the absorber as described in <26> or <27>.
<29>
A method for producing an absorbent article comprising a liquid-retaining absorbent body, a top sheet disposed on the skin facing surface side of the absorbent body, and a back sheet disposed on the non-skin facing surface side of the absorbent body,
The manufacturing method of an absorbent article which manufactures the said absorber by the method in any one of said <1>-<28>.

Hereinafter, the present invention will be described in more detail with reference to examples.
[Example 1]
Using the following absorbent sheet (absorbing layer) as the absorbent sheets 401 and 402, a strip-shaped absorber precursor 4a having a cross-sectional structure shown in FIGS. 1 and 2 was produced.
The strip-shaped absorber precursor 4a was subjected to the formation of the vertical slits 43 and the softening process for the precursor with slits using the apparatus shown in FIGS. 3 and 5 to obtain an absorber with slits. .
The diameters of the first to third rolls were all 37 mm, and the arrangement was as shown in Table 1 and FIG. The length of the linear slit 43 extending in the conveying direction of the precursor with slit was 20 mm, and was a length corresponding to 1.08 times the radius (curvature radius) of each roll.

Absorbent sheet: Cross-linked cellulose fiber, softwood pulp, and superabsorbent polymer supplied in an air stream were deposited at a weight ratio of 5: 2: 3, and then solidified with PVA (2.4% by weight) as an adhesive A dry sheet was used. The main body absorbent sheet 401 has a basis weight of 75 g / m ² and a thickness of 0.45 mm, and the central absorbent sheet 402 has a basis weight of 80 g / m ^{2 and a} thickness of 0.50 mm. The basis weight was measured according to the method described in JIS-P8124, and the thickness was measured according to JIS-P8118: 1998. However, the thickness was measured using a peacock-made desk thickness gauge, and a thickness of 2.5 g / cm ² was measured by placing a 5 cm × 5 cm measuring plate.
[Examples 2 to 4]
For Examples 2 and 3, the arrangement of the first to third rolls, and for Example 4, the arrangement of the first to third rolls and the introduction position of the absorber precursor 4a to the first roll are changed. Except that, an absorber with a slit was obtained in the same manner as in Example 1. Regarding the arrangement of the first to third rolls, Example 2 is shown in Table 1 and FIG. 8 (b), Example 3 is shown in Table 1 and FIG. 8 (c), and Example 4 is shown in Table 1. 1 and as shown in FIG.

[Comparative Example 1]
Except not performing a bending process, it carried out similarly to Example 1, and obtained the absorber with a slit.

[Evaluation]
About the absorber obtained by the Example and the comparative example, the bending rigidity in the longitudinal direction center part of a multilayer part was measured with the following method, and the result was shown in Table 1.
[Measurement method of bending stiffness]
The absorber bending stiffness was evaluated according to JIS L-1096 (General Textile Testing Method). As an evaluation device, a handometer (model: HOM-3) manufactured by Daiei Scientific Instruments Co., Ltd. was used. The width of the groove of the handometer was set to 20 mm.
The obtained absorber with slit was placed on the support table of the handometer so that the longitudinal center of the multilayer portion of the absorber is located at the center of the groove, and the absorber was bent in the width direction. The bending stiffness at the time was evaluated.

  From the comparison of the results shown in Table 1, it can be seen that according to the method of the present invention, the peripheral edge of the slit is flexible, and an absorbent body excellent in flexibility as a whole is efficiently produced.

1 Sanitary napkin (absorbent article)
2 Top sheet 3 Back sheet 4 Absorber 401 Main body absorbent sheet 402 Central absorbent sheet 42 Multi-layer part 43 Vertical slit 45 Back slit 4a Absorber precursor 4 'Absorber precursor 5 with slit formed Absorbent main body 7 Wing part DESCRIPTION OF SYMBOLS 10 Side sheet 60 Cutting device 61 Cutter roll 62 Anvil roll 63, 64 Cutting blade 70, 70A Bending process means 71 1st roll (winding part)
72 2nd roll 73 3rd roll A Front part B Excretion part opposing part C Back part X Longitudinal direction Y Lateral direction

Claims (4)

While conveying the absorber precursor in one direction, making a cut in the thickness direction of the absorber precursor, and manufacturing a absorber having a slit,
The absorber precursor is sandwiched between a cutter roll having a cutting blade on the peripheral surface and an anvil roll that receives the cutting blade of the cutter roll, and the absorber is cut along the thickness direction of the absorber precursor. A slit forming step of forming a slit having a squeezed portion around the absorber precursor by proceeding into the precursor;
The absorbent precursor to form the slits, and and a softening step of softening the compressed portion by deforming wound around the winding portion of the bending processing means,
The absorber has a laminated structure having a plurality of absorption layers,
In the slit forming step, a pressure-bonding portion in which a plurality of absorption layers are pressure-bonded is formed as the pressing portion, and in the softening step, at least one absorption layer in the pressure-bonding portion is separated, and the pressure-bonding portion the thereby softening, manufacturing method of the absorbent body. The bending processing means, as the winding unit comprises at least one of the rolls, at least one of the rolls, embracing angle of the absorber precursor to form the slit 10 degrees to 180 degrees or less The manufacturing method of the absorber of Claim 1 which exists. The winding section has a plurality of suction holes on the surface, said absorbent precursor to form the slit deforms while maintaining the surface by suction, an absorbent body according to claim 1 or 2 Production method. The bending processing means includes a plurality of said winding portion, said absorbent precursor to form the slits, are bent in the S-shaped cross-section, according to any one of claims 1 to 3 Manufacturing method of absorber.

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