JP5822380B2 - Absorber manufacturing method - Google Patents

Description

  The present invention relates to a method for producing absorbent bodies for various absorbent articles including sanitary napkins and disposable diapers.

  In various absorbent articles such as sanitary napkins, in order to improve the adhesion of the absorbent article to the body, or to improve the prevention of liquid leakage, excretion facing the excretory part of the wearer There is known a technique of providing a protruding portion in which an absorbent body protrudes in a convex shape from a portion facing portion or the excretory portion facing portion to a portion corresponding to a wearer's buttocks. Further, in order to improve the prevention of liquid leakage in the absorbent article or to improve the wearability of the absorbent article, the surface sheet and the absorbent body are consolidated on the skin facing surface side of the absorbent article. It is also known to form a groove.

  For example, in Patent Document 1, a leak-proof groove is formed at a position spaced a predetermined distance from the side portion of the middle-high portion, and the separation region between the leak-proof groove and the side portion of the middle-high portion is more than the leak-proof groove portion absorber. An absorbent article is described in which a compressed absorbent region having a lower density and a higher density than the mid-high portion absorbent is formed. The compressed absorber region is formed in a step shape that is thicker than the leak-proof groove portion absorber and thinner than the standard portion of the absorber. According to the absorbent article described in the same document, it is possible to increase the height of the mid-high portion without increasing the total thickness of the absorber, and to promote the diffusion of absorbed menstrual blood and the like. It is said that the surface material can be prevented from being broken even if there is a difference in height between the top surface of the middle and high portions and the bottom surface of the leak-proof groove.

  Apart from the technique described in Patent Document 1, the applicant first forms a three-dimensional projecting portion on the skin-facing surface of an absorbent article in which an absorbent layer is interposed between the top sheet and the back sheet. And the manufacturing method of the absorbent article which forms a recessed part in the outer periphery of this protrusion part was proposed (refer patent document 2). In this method, a first roll formed with a concave space portion for forming the projecting portion and a ridge portion for forming the concave portion, and a second roll disposed at a predetermined distance from the first roll, In the meantime, the protruding portion is formed and the upper portion is formed by conveying and pressing the absorbent layer together with the top sheet.

JP 2002-345888 A JP-A-10-323368

  The absorber described in each of the above-mentioned documents has a single-layer structure in which a liquid absorbent material such as pulp is simply stacked, and a separately prepared lower-layer absorber and upper-layer absorber are laminated. A multilayered absorbent body is also known. In an absorbent article provided with an absorbent body having a multilayer structure, an external force may be applied to the absorbent body due to the wearer's movement in the wearing state, and the upper absorbent body may be displaced from an appropriate position. Such misalignment may cause liquid leakage.

  In addition, in the process of manufacturing an absorbent article having a multilayered structure, the upper layer absorber is displaced from an appropriate position due to vibration of the conveyance while the absorber is being conveyed by the conveyance line. Sometimes. Such misalignment may cause a decrease in product yield.

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

The present invention is a method for producing an absorbent body of an absorbent article having a protruding portion protruding toward the excretion portion of the wearer in the excretion portion facing area, having a thickness greater than that of the peripheral portion,
Absorption having a lower layer located on the side far from the wearer in the wearing state of the article, and an upper layer disposed on the upper surface of the lower layer, located on the side closer to the wearer and having a peripheral edge smaller than the peripheral edge of the lower layer Supplying a body precursor to a compression device and compressing the absorber precursor;
In the step, a portion of the absorber precursor corresponding to at least a part of a peripheral region of the upper layer in a plan view of the absorber precursor is a center in the width direction of the upper layer in the plan view of the absorber precursor. The manufacturing method of the absorber which compresses stronger than the site | part corresponding to an area | region and unifies an upper layer and a lower layer is provided.

Further, the present invention is a method for manufacturing an absorbent article comprising an absorbent body having a protruding portion projecting toward the excretion portion of the wearer in a region opposite to the excretion portion, which is thicker than the peripheral portion. And
Absorption having a lower layer located on the side far from the wearer in the wearing state of the article, and an upper layer disposed on the upper surface of the lower layer, located on the side closer to the wearer and having a peripheral edge smaller than the peripheral edge of the lower layer Prepare body precursors,
A surface sheet is disposed on the upper layer of the absorber precursor;
Supplying the absorber precursor in a state where the topsheet is disposed to a compression device, and compressing the absorber precursor together with the topsheet;
In the step, a portion of the absorber precursor corresponding to at least a part of a peripheral region of the upper layer in a plan view of the absorber precursor is a center in the width direction of the upper layer in the plan view of the absorber precursor. The manufacturing method of the absorbent article which compresses stronger than the site | part corresponding to an area | region and unifies an upper layer and a lower layer is provided.

  According to the method for manufacturing an absorbent body of the present invention, it is possible to effectively prevent the upper layer absorbent body from being displaced in the wearing state of the absorbent article or in the process of manufacturing the absorbent article.

Fig.1 (a) is a partially broken perspective view which shows an example of the absorbent article provided with the absorber suitably manufactured according to the manufacturing method of this invention, FIG.1 (b) is absorption shown in FIG. It is the disassembled perspective view which looked at the absorber in a property article from the lower layer absorber side. FIG. 2 is a schematic diagram showing a longitudinal section in the width direction at the excretory part-facing part of the absorbent body in the absorbent article shown in FIG. 1. FIG. 3 is a schematic view showing an example of an apparatus used in the method for producing an absorbent body of the present invention. FIG. 4 is an exploded perspective view of a main part of a fiber stacking drum in the first fiber stacker used for manufacturing the lower layer. FIG. 5 is a perspective view of an absorber precursor manufactured using the apparatus shown in FIG. FIG. 6 is a diagram showing a positional relationship between the compression device and the absorber precursor supplied to the compression device. FIG. 7 is a schematic diagram showing a state where the absorber precursor supplied to the compression device is compressed. FIGS. 8A and 8B are schematic views showing a state in which the absorber precursor supplied to the compression device is compressed. FIGS. 9A to 9D are schematic views (corresponding to FIG. 6) showing another embodiment of the compression apparatus.

  The present invention will be described below based on preferred embodiments with reference to the drawings. FIG. 1 shows an example of an absorbent article including an absorbent body that is preferably manufactured according to the manufacturing method of the present invention. The absorbent article of this embodiment is a sanitary napkin. The napkin 1 includes a top sheet 2 that forms a skin facing surface, a back sheet 3 that forms a non-skin facing surface, and an absorbent body 4 interposed between the two sheets 2 and 3, and has a substantially vertically long shape. I am doing.

  As shown in FIG. 1, the napkin 1 has an excretory part facing area A disposed opposite to the excretion part (vaginal opening) of the wearer in the wearing state, and a rear extending in the longitudinal direction rearward from the excretion part facing part area A It has the area | region B and the front area C extended in the longitudinal direction front from this excretion part opposing part area | region A.

  In the present specification, the skin facing surface is a surface directed to the skin side of the wearer in the wearing state of the absorbent article (sanitary napkin) in the absorbent article (sanitary napkin) or its constituent members. The non-skin-facing surface is a surface of the absorbent article (sanitary napkin) or a member thereof directed to the skin side and the opposite side (clothing side) when the absorbent article (sanitary napkin) is worn. The longitudinal direction is a direction along the long side of the absorbent article (sanitary napkin) or its constituent members, and the width direction is a direction orthogonal to the longitudinal direction.

  The top sheet 2 and the back sheet 3 have a peripheral edge larger than the peripheral edge of the absorber 4 and extend outward from the peripheral edge of the absorber 4. And the extended surface sheet 2 and the back surface sheet 3 are joined in those peripheral edges, and the peripheral junction part is formed.

  The napkin 1 has a pair of left and right wings 5 that extend in the width direction of the napkin 1 in the excretion part-facing area A. The wing part 5 is formed by joining the top sheet 2 and the back sheet 3. The wing portion 5 is used to prevent the napkin 1 from being displaced in the wearing state by being folded back to the outer surface side of the crotch portion in the wearer's shorts and fixed to the crotch portion in the wearing state of the napkin 1.

  The non-skin facing surface of the napkin 1, that is, the outer surface of the back sheet 3, is directed to the inner surface of the crotch portion of the shorts when the napkin is worn. An adhesive part (not shown) for fixing the napkin 1 to the crotch part of the shorts is provided on the non-skin facing surface. Moreover, the adhesion part (not shown) is provided also in the non-skin opposing surface of the wing part 5 mentioned above. These adhesive portions are provided by applying a hot melt adhesive to a predetermined location. The adhesive part is protected by a release sheet (not shown) made of a film, a nonwoven fabric, paper, or the like before the napkin 1 is used.

  The absorbent body 4 has a rectangular shape or an oval shape with rounded corners in plan view, and is arranged in the central region in the article width direction with the longitudinal direction thereof coinciding with the longitudinal direction of the napkin 1. The absorbent body 4 is made of, for example, an absorbent core made of a liquid absorbent fiber material such as pulp fiber or a mixture of a liquid absorbent fiber material and a super absorbent polymer. It is coated with a core wrap sheet (not shown) made of nonwoven fabric. Between the top sheet and the absorbent body 4 and / or between the absorbent body 4 and the back sheet 3 is an adhesive (hot melt adhesive or the like) that has been coated with a pattern such as a dot, spiral, or stripe. It is joined.

  As shown in FIGS. 1 and 2, the absorbent body 4 has a protruding portion 42 that is thicker than the peripheral portion 41 and protrudes toward the excretion portion at the excretion portion facing portion A. Specifically, the absorbent body 4 is arranged on the upper surface (that is, the skin-facing surface) of the lower-layer absorbent core 40a in the vertically long lower-layer absorbent core 40a having a length that extends over almost the entire length of the napkin 1 and the excretory portion-facing portion A. And a vertically long upper absorbent core 40b. The lower-layer absorbent core 40a and the upper-layer absorbent core 40b are each manufactured in a separate manufacturing process, stacked after that, and integrated by a method described later. Therefore, the absorber 4 has a two-layer structure or a multilayer structure including the lower layer absorbent core 40a and the upper layer absorbent core 40b. The lower layer absorbent core 40a and the upper layer absorbent core 40b are covered with a core wrap sheet (not shown) in the laminated state. Or the lower layer absorption core 40a and the upper layer absorption core 40b may each be separately covered with a core wrap sheet (not shown), and may be laminated in a covered state with the core wrap sheet.

  In plan view, the periphery of the upper absorbent core 40b is smaller than the periphery of the lower absorbent core 40a, and the periphery of the upper absorbent core 40b is located inside the periphery of the lower absorbent core 40a. In plan view, the length and width of the upper absorbent core 40b are smaller than the length and width of the lower absorbent core 40a. The upper layer absorbent core 40b is arranged in the center region in the article width direction of the lower layer absorbent core 40a in the excretory part facing part A with its longitudinal direction coinciding with the article longitudinal direction.

  The thickness of each of the lower layer absorbent core 40a and the upper layer absorbent core 40b is set to an appropriate value according to the specific application of the napkin 1 (for example, whether it is for daytime or nighttime use). Generally speaking, the thickness of the lower absorbent core 40a is preferably 1 to 10 mm, more preferably 1 to 5 mm, and the thickness of the upper absorbent body 40a is preferably 1 to 20 mm, more preferably 1 to 10 mm. .

  The lower layer absorbent core 40 a includes a base part 43 and a plurality of block-like absorbent parts 44 located on one surface of the base part 43. The upper absorbent core 40b is disposed on the base 43 side of the lower absorbent core 40a. There is a space between adjacent block-shaped absorbing portions 44, and each block-shaped absorbing portion 44 is individually independent. As will be described later, the base portion 43 and the block-shaped absorbing portion 44 are integrally formed. A plurality of the block-shaped absorbent portions 44 are arranged in a row at a predetermined interval along the longitudinal direction of the absorbent body 4. Moreover, the block-shaped absorption part 44 is arrange | positioned by the row | line | column of this block-shaped absorption part 44 in multiple rows at predetermined intervals along the width direction of an absorber.

  As shown in FIG. 2, in the cross-sectional view along the article width direction of the excretory part facing part A, the protruding part 42 and its peripheral part 45 in the absorbent body 4 (part of a predetermined width adjacent to the protruding part 42 in the article width direction). In the absorber central region 46, the central portion in the article width direction of the absorber central region 46 is a central low density portion 47 having a relatively low density. At the same time, the side part adjacent to the central part and including at least a part of the side part of the projecting part 42 (the part of the side part closer to the outside in the article width direction) has a relatively high density side part. A high density portion 48 is formed. The lower-layer absorbent core 40a and the upper-layer absorbent core 40b described above are mainly integrated in the lateral high-density portion 48.

  The central low density portion 47 is a portion where the density of all the constituent materials (fibers, water-absorbing polymer, etc.) is low in comparison with the side high density portion 48. The side high density portion 48 is a portion where the density of all the constituent materials is high as compared with the central low density portion 47. The central low density portion 47 has a substantially uniform density over the entire area. On the other hand, the density of the high-density side portion 48 increases from the inside toward the outside in the article width direction (Y direction in the figure). That is, in the side high-density portion 48, the portion adjacent to the central low-density portion 47 in the article width direction in the projecting portion 42 has the lowest density of all the constituent materials and is located outside the middle-high portion 42 in the article width direction. The peripheral part 45 has the highest density of all constituent materials.

  When the manufacturing method of the absorbent article containing the absorber 4 which has the above structure is demonstrated, first it will become the origin of the lower layer 60 used as the origin of the lower layer absorption core 40a, and the upper layer absorption core 40b using the apparatus shown in FIG. The upper layer 62 is manufactured. The lower layer 60 is located on the side far from the wearer when the napkin is worn. The upper layer 62 is located on the side closer to the wearer when the napkin is worn. The apparatus shown in FIG. 2 includes a first stacking machine 50A and a second stacking machine 50B, which are two stacking machines. The first stacking machine 50A is located on the upstream side in the transport direction of the absorber precursor 4 ′ having the lower layer 60 and the upper layer 62. The second pile machine 50B is located on the downstream side of the first pile machine 50A. The first stacking machine is for manufacturing the lower layer 60. The second stacking machine 50B is for producing the upper layer 62.

  Each of the fiber stackers 50A and 50B has fiber stacking drums 51A and 51B that can rotate in the same direction as the conveying direction of the absorber precursor 4 '. Furthermore, each of the fiber stacking machines 50A and 50B has fiber stacking ducts 52A and 52B provided with a hood that covers a part of the peripheral surface of the fiber stacking drums 51A and 51B. The lower layer and upper layer raw materials are deposited in the recesses 53A and 53B provided on the circumferential surfaces of the stacking drums 51A and 51B through the stacking ducts 52A and 52B. Each of the recesses 53A and 53B has a shape complementary to the shapes of the target lower layer 60 and upper layer 62.

  FIG. 4 shows an exploded perspective view of a main part of the stacking drum 53A in the first stacking machine 50A used for manufacturing the lower layer 60. The fiber stacking drum 53A has a cylindrical frame body 54 made of a metal rigid body, a gas-permeable perforated plate 55 fixed on the outer surface side of the frame body 54, and an outer surface side of the perforated plate 55. Pattern forming plate 56. These members are integrally fixed by various known fixing methods such as bolting and adhesive.

  The frame body 54 has a shape in which a ladder is formed in an annular shape and upper and lower ends are connected, and has a communication hole 54a penetrating the inner and outer surfaces at each of the portions corresponding to the concave portion 53A described above. The perforated plate 55 has a large number of pores, and can transmit only air without transmitting the fiber material as the raw material of the absorbent body supplied on the air flow. As the perforated plate 55, those conventionally used in this type of fiber stacking device can be used without particular limitation. For example, a metal or resin mesh plate or a metal or resin plate formed with a large number of pores by etching or punching can be used.

  The pattern forming plate 56 has an outer surface 56a that forms the outer peripheral surface of the stacking drum 51A, and an inner surface 56b that faces the rotating shaft of the stacking drum 51A, and a recess 53A is formed between the outer surface 56a and the inner surface 56b. A space having a shape corresponding to the three-dimensional shape is provided. A crosspiece member 57 is provided on the pattern forming plate 56. The crosspiece members 57 are arranged in a lattice shape in the rotation direction of the fiber stacking drum 51 </ b> A and the direction orthogonal thereto. The crosspiece member 57 is provided near the inner surface 56b, and a space without the crosspiece member 57 is formed on the outer surface 56a side of the recess 53A. A large number of fiber spaces 58 taken in by the four-side crosspieces 57 are provided.

  Returning to FIG. 3, by operating the first stacking machine 50 </ b> A, the stacking drum 51 </ b> A is rotated and sucked inward from the peripheral surface thereof, so that the suction is placed in the recess 53 </ b> A of the stacking drum 51 </ b> A. The lower layer 60 is formed by depositing raw materials made of a liquid fiber material or a superabsorbent polymer. In this case, the raw material is first deposited in the stacking space 58 of the pattern forming plate 56 shown in FIG. 4 to form a portion corresponding to the block-shaped absorbent portion 44 described above. When the fiber is further advanced, a portion connecting the raw material stacked in each fiber space 58 is formed in the entire region of the recess 53A in a space without the crosspiece member 57 on the outer surface 56a side of the recess 53A. This connecting portion corresponds to the base portion 43 described above. Therefore, the lower layer 60 manufactured by the first stacking machine 50A includes the base portion and a number of block-shaped absorbent portions arranged on one surface of the base portion, like the lower layer absorbent core 40a in the target absorbent body 4. It will have.

  The lower layer 60 formed in each recess 53A of the stacking drum 51A is temporarily transferred to the peripheral surface of the transfer drum 59 that rotates in the opposite direction to the stacking drum 51A. The transfer of the lower layer 60 can be successfully performed by sucking the transfer drum 59 from the circumferential surface to the inside while blowing air from the inside to the circumferential surface of the fiber stack drum 51A at the transfer position. it can. The lower layer 60 transferred to the transfer drum 59 is transferred and placed on one surface of the core wrap sheet 61 that runs in the same direction as the rotation direction of the transfer drum 59. In the lower layer 60 placed on the core wrap sheet 61, the block-shaped absorbent portion in the lower layer 60 faces the core wrap sheet 61, and the base portion faces upward.

  As the core wrap sheet 61 travels, the lower layer 60 is continuously conveyed to the second stacking machine 50B sequentially and at predetermined intervals. In the second stacking machine 50B, an upper layer 62 that is a precursor of the upper absorbent core 40b in the target absorbent body 4 is formed. The upper layer 62 is formed by depositing a raw material made of a liquid absorbent fiber material or a superabsorbent polymer in a recess 53B provided on the peripheral surface of the fiber drum 51B in the second fiber stacker 50B. The recess 53B has a shape complementary to the shape of the upper layer 62. The upper layer 62 formed in the recess 53B is placed on the upper surface of the lower layer 60 being conveyed, that is, the surface on the base portion side.

  When the upper layer 62 is placed on the lower layer 60, the core wrap sheet 61 positioned under the lower layer 60 is wound up by a known winding means 66, and the lower layer 60 and the upper layer 62 are integrally formed by the core wrap sheet 61. Cover. In this way, the absorber precursor 4 'shown in FIG. 5 is formed. The precursor 4 ′ has a lower layer 60 and an upper layer 62 placed thereon. The block-shaped absorption part 60a in the lower layer 60 faces downward. The base portion 60 b in the lower layer 60 faces upward and faces the upper layer 62.

  The absorber precursor 4 ′ thus manufactured is conveyed to the compression device 63 as the core wrap sheet 61 travels as shown in FIG. 3. The compression device 63 includes a first roll 64 and a second roll 65 that are a pair of roll members. The pair of rolls 64 and 65 are disposed above and below the sheet 61 with the core wrap sheet 61 interposed therebetween. The rolls 64 and 65 are arranged such that their axes are orthogonal to the traveling direction of the core wrap sheet 61. Furthermore, the rolls 64 and 65 are arranged at intervals such that a predetermined clearance is generated between their peripheral surfaces, and the absorber precursor 4 ′ inserted between the rolls 64 and 65 is compressed.

  FIG. 6 shows an arrangement relationship between the compression device 63 and the absorber precursor 4 ′ supplied to the compression device 63. As illustrated in FIG. 6, at least one of the pair of rolls 64 and 65 included in the compression device 63 is a roll having a pressing portion. Specifically, the compression device 63 has a first roll 64 made of a flat roll and a second roll 65 as a roll having a pressing portion. The first roll 64 is made of metal, for example, and its peripheral surface is smooth. The second roll 65 can also be made of metal. The widths of the first roll 64 and the second roll 65 are both slightly larger than the width of the lower layer 60 in the absorber precursor 4 '. The first roll 64 and the second roll 65 have substantially the same width.

  As shown in FIG. 6, the second roll 65 is a stepped roll. Specifically, the second roll 65 has a small-diameter portion 65a located in the center area in the roll axis direction, and is located in the side area in the roll axis direction, and each side area of the upper layer 62 in the absorber precursor 4 ′. And a large-diameter portion 65b as a pressing portion to be compressed. The radius R1 of the roll at the small diameter portion 65a is smaller than the radius R2 of the roll at the large diameter portion 65b (R1 <R2). The peripheral surfaces of the small diameter portion 65a and the large diameter portion 65b are smooth. The width of the small diameter portion 65a (that is, the length in the roll axis direction) is smaller than the width of the upper layer 62 in the absorber precursor 4 '. In a state where the absorber precursor 4 ′ is supplied to the compression device 63, the position of the central region of the upper layer 62 in the precursor 4 ′ is substantially coincident with the position of the small diameter portion 65 a. On the other hand, the side region of the upper layer 62 faces the large-diameter portion 65b. The large diameter portion 65 b faces the side region of the upper layer 62 so as to straddle the side edge of the upper layer 62.

  By supplying the absorber precursor 4 ′ to the compression device 63 in the above positional relationship, as shown in FIG. 7, each side region 62 a that is at least a part of the peripheral region in the upper layer 62 and the lower layer 60. Of these, the portion corresponding to the side region 62a is strongly compressed by the large diameter portion 65b. In other words, portions of the absorber precursor 4 ′ corresponding to the side regions 62 a of the upper layer 62 in the plan view of the absorber precursor 4 ′ are strongly compressed. As a result, the upper layer 62 and the lower layer 60 are successfully integrated in the side region of the upper layer 62. In this case, the compressive force is strongest at the position of the side region 62 a of the upper layer 62. As a result, the laterally dense portion 48 described above is formed in the obtained absorbent body 4. Moreover, since the side area 62a of the upper layer 62 is crushed by this compression, as shown in FIG. 7, the width W1 of the upper absorbent core 40b in the obtained absorbent body 4 is the width W2 of the upper layer 62 that is the precursor. Narrower than.

  On the other hand, the central region in the width direction of the upper layer 62 enters the gap formed by the small diameter portion 65a of the second roll 65, which is a stepped roll, and deforms to fill the gap. Therefore, the compressive force is small or hardly applied to the portion corresponding to the central region in the width direction of the upper layer 62 in the plan view of the absorber precursor 4 ′ compared to the portion corresponding to the side region. As a result, the obtained absorber 4 is formed with the central low-density portion 47 (see FIG. 2) described above.

  Furthermore, a portion 60 ′ located on the side of the lower layer 60 with respect to the side region of the upper layer 62 is compressed by the large diameter portion 65 b alone. Therefore, the portion 60 'is more rigid than before compression. This leads to an advantage that when the absorbent article is worn, when the external force resulting from the movement of the wearer is applied to the part 60 ′, the part 60 ′ is difficult to bend. In addition, since the portion 60 ′ is thinner than before compression, it also leads to an advantage that the feeling of wearing the absorbent article is improved.

In particular, when the block-shaped absorbent portion 60a (see FIG. 5) is formed on the lower layer 60, longitudinally plurality arranged in a row block-like absorbing portion 60a of the lower layer 60, the block-shaped absorbent portion 60a Compressed along the columns. The linear compression site | part which has the predetermined width formed by this compression will be in the state by which the high compression site | part and the low compression site | part were arrange | positioned alternately along the extension direction. The highly compressed portion is a portion formed mainly by compressing the block-shaped absorbent portion 60 a in the lower layer 60 and the side region of the upper layer 62. The low compression portion is a portion formed mainly by compressing the space between the block-shaped absorption portions 60 a in the lower layer 60 and the side region of the upper layer 62. In the absorbent body 4 obtained by forming the compressed portion in which the high compression portion and the low compression portion are alternately arranged, the low compression portion becomes a bending point, and the absorber 4 bends in the longitudinal direction. There is an advantage that it becomes easy. In addition, there is an advantage that the high compression portion exhibits an anchor effect (spike-like role) and the upper layer 62 and the lower layer 60 are more difficult to be displaced.

  In the compression step, the thickness of the intended absorber 4 can be adjusted by adjusting the level difference of the second roll 65 that is a stepped roll. As described above, when the radius of the small diameter portion 65a is R1, and the radius of the large diameter portion 65b is R2, the step H of the stepped roll is represented by R2-R1. When this level difference H is large, as shown in FIG. 8A, since the degree of compression of the central region of the upper layer 62 in the absorber precursor 4 ′ is small, the total thickness T of the obtained absorber 4 is compared. Become bigger. On the other hand, as shown in FIG. 8B, when the step H of the second roll 65, which is a stepped roll, is small, the degree of compression in the central region of the upper layer 62 in the absorber precursor 4 ′ is reduced. Since it is larger than the case shown in FIG. 8 (a), the total thickness T of the obtained absorber 4 is smaller than that shown in FIG. 8 (a).

  FIGS. 9A to 9D show another embodiment of the compression process. Note that the description regarding the embodiments shown in FIGS. 6 to 8 described above is appropriately applied to points that are not particularly described regarding these embodiments. In the compression step shown in FIG. 9A, the compression device 63 to be used is the same as that shown in FIG. 6 described above. However, in the present embodiment, the method of supplying the absorber precursor 4 ′ supplied to the compression device 63 is different from the embodiment shown in FIG. 6. Specifically, in the present embodiment, the lower layer 60 in the absorber precursor 4 is a second roll 65 that is a roll having a pressing portion, ie, a stepped roll, as a pressurizing unit. The body 4 'is supplied and compression is performed. According to the present embodiment, in addition to the effect obtained in the embodiment shown in FIG. 6 described above, the positional displacement of the upper layer 60 is less likely to occur during compression, and there is an advantageous effect that the compression width is stabilized. Is done. This is because the upper layer 62 is compressed while being held by the lower layer 60 when pressed with a stepped roll from the lower layer 60 side.

  In the compression step shown in FIG. 9 (b), the compression device 63 used is a first roll 64 made of a flat roll, and a second roll 66 made of a partial press roll that is a roll having a pressing portion as a pressurizing means. And have. The width of the first roll 64 made of a flat roll is slightly larger than the width of the lower layer 60 in the absorber precursor 4 '. The second roll 66 made of a partial press roll is narrower than the first roll 64. The width of the second roll 66 is wider than the width of the upper layer 62. However, it is narrower than the width of the lower layer 60. At the same time, the second roll 66 includes a small-diameter portion 66a located in the central region in the roll axis direction, a large-diameter portion 66b located in the side region in the roll axial direction, and compressing each side region 62a of the upper layer 62. It has. The large diameter portion 66 b of the second roll 66 is located inside the both side edges of the lower layer 60. In a state where the absorber precursor 4 ′ is supplied to the compression device 63, the position of the central region of the upper layer 62 in the precursor 4 ′ is substantially coincident with the position of the small diameter portion 66 a. On the other hand, the position of the side region of the upper layer 62 substantially coincides with the position of the large diameter portion 66b. The large diameter portion 66 b and the upper layer 62 are in a positional relationship such that the large diameter portion 66 b straddles the side edge of the upper layer 62. According to the present embodiment, the compressive force from the large-diameter portion 66b is more effectively transmitted to the part to be compressed, the part is more easily compressed, and the periphery of the part does not have to be crushed more than necessary. The effect is played.

  In the compression step shown in FIG. 9C, the compression device 63 used is a first roll 64 made of a flat roll, and a second roll 67 made of an embossing roll, which is a roll having a pressing part, as a pressing means. have. The widths of the first roll 64 and the second roll 67 are both slightly larger than the width of the lower layer 60 in the absorber precursor 4 '. The 2nd roll 67 which consists of an embossing roll has a some uneven | corrugated processed part as a press site | part. In detail, the 2nd roll 67 has a pair of uneven | corrugated processed part 67a along the circumferential direction of the 2nd roll 67 in the site | part corresponding to each side region of the upper layer 62 in absorber precursor 4 '. Yes. The concavo-convex portion 67 a is formed with a predetermined width in the roll axis direction of the second roll 67. Of the peripheral surface of the second roll 67, a portion other than the portion where the concave and convex portion 67a is formed is a smooth surface. In a state where the absorber precursor 4 ′ is supplied to the compression device 63, the position of the central region of the upper layer 62 in the precursor 4 ′ is substantially coincident with the position between the pair of uneven processing portions 67 a. On the other hand, the position of the side region of the upper layer 62 is substantially coincident with the position of the concavo-convex portion 67a. The concavo-convex portion 67 a and the upper layer 62 are in a positional relationship such that the concavo-convex portion 67 a straddles the side edge of the upper layer 62. Examples of the concavo-convex pattern in the concavo-convex processed portion 67a include, but are not limited to, a pattern in which a large number of dot-shaped convex portions are regularly arranged. According to the present embodiment, the dot portion has a higher pressure and is easier to compress than using a stepped roll having a flat surface as shown in FIG. The advantageous effect that the compression part becomes flexible as compared with a stepped roll having a flat surface as shown in FIG.

    In the compression step shown in FIG. 9 (d), the compression device 63 used is a first roll 64 made of a flat roll, and a second roll made of a partial press embossing roll that is a roll having a pressing portion as a pressurizing means. 68. The width of the first roll 64 made of a flat roll is slightly larger than the width of the lower layer 60 in the absorber precursor 4 '. The second roll 68 made of a partial press embossing roll is narrower than the first roll 65. The width of the second roll 66 is wider than the width of the upper layer 62. However, it is narrower than the width of the lower layer 60. At the same time, the second roll 66 includes a small-diameter portion 68a located in the central region in the roll axis direction, a large-diameter portion 68b located in the side region in the roll axial direction, and compressing each side region 62a of the upper layer 62. It has. The peripheral surface of the small diameter portion 68a is smooth. On the other hand, the large diameter portion 68b is an uneven surface. In a state where the absorber precursor 4 ′ is supplied to the compression device 63, the position of the central region of the upper layer 62 in the precursor 4 ′ is substantially coincident with the position of the small diameter portion 68 a. On the other hand, the position of the side region of the upper layer 62 substantially coincides with the position of the large diameter portion 68b. The large diameter portion 68 b and the upper layer 62 are in a positional relationship such that the large diameter portion 68 b straddles the side edge of the upper layer 62. Examples of the concavo-convex pattern on the concavo-convex processed surface of the large-diameter portion 68b include, but are not limited to, a pattern in which continuous oblique lattice-shaped convex portions are regularly arranged. According to the present embodiment, since the contact area is small, it is easy to apply a high pressure, and the pressure is effectively transmitted to the site to be compressed. Played.

  In the embodiment shown in FIGS. 9B to 9D, the lower layer 60 in the absorber precursor 4 ′ is compressed so as to face the second rolls 66, 67, and 68 which are pressurizing means. Alternatively, compression may be performed so that the upper layer 60 of the precursor 4 ′ faces the pressurizing means.

  When the absorbent body 4 is thus obtained, the back sheet 3 is then disposed on the outer surface of the absorbent body 4 on the lower absorbent core 40a side, and the upper absorbent core 40b side of the absorbent body 4 is disposed. The surface sheet 2 is arranged on the outer surface. And the objective sanitary napkin 1 is obtained by joining both the sheets 2 and 3 extended from the periphery of the absorber 4. FIG. As described above, the obtained sanitary napkin 1 is provided with an adhesive part (not shown) for fixing to the crotch part of the shorts. Moreover, it is folded in three in the longitudinal direction together with the individual packaging sheet and is individually packaged. In the napkin 1 obtained in this way, the upper absorbent core 40b is less likely to be displaced during the manufacturing process, and even in the worn state, the upper absorbent core 40b is less likely to be displaced.

  In the above embodiment, the absorber precursor 4 ′ having the upper layer 62 and the lower layer 60 is compressed to obtain the absorber 4. Instead, the surface of the absorber precursor 4 ′ on the upper layer 62 in the absorber precursor 4 ′ is obtained. The sheet 2 may be disposed, and the absorber precursor 4 ′ in a state where the surface sheet 2 is disposed may be supplied to the compression device, and the absorber precursor 4 ′ may be compressed together with the surface sheet 2.

  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, in the absorbent body 40 in the above-described embodiment, the upper absorbent core 40b is positioned on the base 43 side of the lower absorbent core 40a, but instead, on the block absorbent part 44 side of the lower absorbent core 40a. The upper absorbent core 40b may be positioned.

  Moreover, although the block-shaped absorption part 44 currently formed in the lower layer absorption core 40a in the said embodiment was arrange | positioned at the grid | lattice form, each block-shaped absorption part 44 is arrange | positioned along the longitudinal direction of the absorber 4 at the line form. Moreover, as long as the row | line | column of this block-shaped absorption part 44 is arrange | positioned at multiple rows along the width direction of the absorber 4, you may arrange | position with another pattern. For example, each block-shaped absorption part 44 may be arranged in a staggered pattern. As for the rows of the block-shaped absorbent portions 44, each of the block-shaped absorbent portions 44 is arranged in a row along the width direction of the absorber 4, instead of being arranged along the longitudinal direction of the absorber 4. In addition to being arranged, the rows of the block-shaped absorbent portions 44 may be arranged in multiple rows along the longitudinal direction of the absorber 4. Furthermore, although the lower layer absorption core 40a in the said embodiment was provided with the base | substrate part 43 and the block-shaped absorption part 44, it replaces with this and does not have the base | substrate part 43 as a lower layer absorption core 40a, but is block-shaped absorption. An absorber having only the portion 44 may be used.

  Moreover, although the lower layer absorption core 40a in the said embodiment was provided with the block-shaped absorption part 44, it replaced with this and does not include the block-shaped absorption part 44 as a lower layer absorption core 40a, but has a substantially uniform thickness. You may use the absorber which has.

  Moreover, in the said embodiment, although the side edge area | region of the upper layer 62 in absorber precursor 4 'was compressed more strongly than the center area, you may compress the whole peripheral area of the upper layer 62 including this side edge area. . Further, the side edge region of the upper layer 62 in the absorber precursor 4 ′ may be compressed without compressing the end region of the upper layer 62 in the article longitudinal direction.

  Moreover, although the upper layer 62 and the lower layer 60 in the said embodiment were intermittently formed in predetermined length, you may change the shape of recessed part 53A, 53B in the apparatus of FIG. 3, and may form continuously. In order to do so, for example, in the stacking drum 51A shown in FIG. 4, a concave portion that is continuous along the circumferential direction of the stacking drum 51A may be provided in the pattern forming plate 56.

  In the above embodiment, after forming the lower layer 60, the upper layer 62 is laminated thereon to form the absorber precursor 4 '. Instead, after forming the upper layer 62, the lower layer 60 is laminated. Thus, the absorber precursor 4 ′ may be formed.

  Moreover, in the said embodiment, although the compression apparatus was provided with a pair of roll member which consists of a roll which has a press part, and a flat roll, it replaces with this and has two rolls which have the same or different press part. It may be used. As a press part in two said rolls, the thing of the form shown to Fig.9 (a) thru | or (d) can be used, for example.

  As the compression device, in addition to the above-described roll-shaped structure, a pair of plate-shaped structures that can contact and separate from each other may be used.

1 Sanitary napkin (absorbent article)
DESCRIPTION OF SYMBOLS 3 Back surface sheet 4 Absorber 40a Lower layer absorber 40b Upper layer absorber 41 Peripheral part 42 Protrusion part 43 Base part 44 Block-shaped absorption part 5 Wing part

Claims (9)

In the excretory part facing area, the manufacturing method of the absorbent body of the absorbent article having a thicker than the peripheral part and having a protruding part protruding toward the excretion part of the wearer,
Absorption having a lower layer located on the side far from the wearer in the wearing state of the article, and an upper layer disposed on the upper surface of the lower layer, located on the side closer to the wearer and having a peripheral edge smaller than the peripheral edge of the lower layer Supplying a body precursor to a compression device and compressing the absorber precursor;
The lower layer includes a base portion and a plurality of block-shaped absorbing portions located on one surface of the base portion, and the upper layer is disposed on the base portion side in the lower layer,
In the step, a portion of the absorber precursor corresponding to at least a part of a peripheral region of the upper layer in a plan view of the absorber precursor is a center in the width direction of the upper layer in the plan view of the absorber precursor. By compressing stronger than the part corresponding to the region, forming a linear compression part having a predetermined width by integrating the upper layer and the lower layer ,
The formed compression site is one in which high compression sites and low compression sites are alternately arranged along the extending direction thereof.
The high compression portion is a portion formed mainly by compressing the block-shaped absorbent portion in the lower layer and the side region of the upper layer,
The said low compression site | part is a manufacturing method of an absorber which is a site | part mainly formed by compressing between the said block-shaped absorption parts in the said lower layer, and the side part area | region of the said upper layer .   The manufacturing method according to claim 1, wherein the compression device includes a pair of roll members including at least a roll having a pressing portion.   The manufacturing method according to claim 2, wherein compression is performed so that an upper layer in the absorber precursor faces a roll having a pressing portion.   The manufacturing method according to claim 2, wherein the compression is performed so that the lower layer in the absorber precursor faces a roll having a pressing portion.   A roll having a pressing part is located in a central area in the roll axis direction, and is located in a side area in the roll axis direction, and of the absorber precursors, the upper layer in a plan view of the absorber precursor The manufacturing method as described in any one of Claim 2 thru | or 4 provided with the large diameter part as a press part which compresses the site | part corresponding to each side part area | region.   The manufacturing method according to claim 5, wherein the roll having the pressing portion has the large-diameter portion positioned on the inner side of both side edges of the lower layer.   The manufacturing method as described in any one of Claim 2 thru | or 6 in which the press part in the roll which has a press part has a some uneven | corrugated processed part. Each block-shaped absorbent portion is arranged in a row along the longitudinal direction or the width direction of the target absorber, and the row of the block-shaped absorbent portions is the width direction or the longitudinal direction of the target absorber. The manufacturing method in any one of Claim 1 thru | or 7 arrange | positioned in multiple rows along. In the excretion part facing area, the thickness is thicker than the peripheral part, and a method for producing an absorbent article comprising an absorbent body having a protruding part protruding toward the excretion part of the wearer,
Absorption having a lower layer located on the side far from the wearer in the wearing state of the article, and an upper layer disposed on the upper surface of the lower layer, located on the side closer to the wearer and having a peripheral edge smaller than the peripheral edge of the lower layer Prepare body precursors,
A surface sheet is disposed on the upper layer of the absorber precursor;
Supplying the absorber precursor in a state where the topsheet is disposed to a compression device, and compressing the absorber precursor together with the topsheet;
The lower layer includes a base portion and a plurality of block-shaped absorbing portions located on one surface of the base portion, and the upper layer is disposed on the base portion side in the lower layer,
In the step, a portion of the absorber precursor corresponding to at least a part of a peripheral region of the upper layer in a plan view of the absorber precursor is a center in the width direction of the upper layer in the plan view of the absorber precursor. By compressing stronger than the part corresponding to the region, forming a linear compression part having a predetermined width by integrating the upper layer and the lower layer ,
The formed compression site is one in which high compression sites and low compression sites are alternately arranged along the extending direction thereof.
The high compression portion is a portion formed mainly by compressing the block-shaped absorbent portion in the lower layer and the side region of the upper layer,
The said low compression site | part is a manufacturing method of an absorbent article which is a site | part mainly formed by compressing between the said block-shaped absorption parts in the said lower layer, and the side part area | region of the said upper layer .

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