JP2009291475A - Absorbent core for sanitary article, and method of manufacturing the same - Google Patents

Abstract

An absorbent core, such as a paper diaper, is provided with a portion with increased water absorption with a highly water absorbent resin.
A water absorbing fiber layer C1 is formed on a mold 11 in a first chamber 21 in which defibrated fibers are pneumatically transported, and the first chamber 21 and the second chamber 22 in which the defibrated fibers are pneumatically transported are formed. Outside, the superabsorbent resin layer C2 that has been molded in a predetermined plane in advance spans both sides including the center in the short direction of the water absorbent fiber layer C1, and one end side in the longitudinal direction of the water absorbent fiber layer C1 or It arrange | positions so that it may extend at least one end side including the center. Thereafter, a growth layer C3 that covers the superabsorbent resin layer C2 by suction through the superabsorbent resin layer C2 is formed in the second chamber 22, and the relative position of the superabsorbent fiber layer C1 and the like is maintained by suction. The mold 11 was conveyed to the mold release position, and these layers were released from the bottom of the mold 11 by applying a positive pressure.
[Selection] Figure 1

Description

  The present invention relates to an absorbent core for sanitary goods such as paper diapers, paper pants, sanitary napkins, incontinence pads, and the like, and a method for manufacturing the same.

  A sanitary article such as a disposable diaper has an absorbent core in a portion along the crotch. Conventionally, as an absorbent core, sheet pulp is pulverized, and the pulverized pulp is molded by sucking it into a suction drum mold under negative pressure, and the molded body is wrapped inside from the water-permeable portion provided in the package. The one that came to be flooded is used. Furthermore, in order to improve the water absorption and water retention of the liquid contained in the excrement, a highly water absorbent resin, such as sodium polyacrylate, which is significantly superior in water absorption and water retention per unit volume than the pulverized pulp layer. It has been practiced to mix the granules in the pulverized pulp (for example, Patent Document 1).

  In the above prior art, the granulated pulp and the superabsorbent resin are pneumatically transported, so that the superabsorbent resin granules are uniformly mixed in the absorbent fiber layer.

Japanese Unexamined Patent Publication No. 63-59463

  However, the absorbent core of sanitary products has a water absorption amount depending on the age and gender of interest, such as the front (abdominal) part for men and the center to the back (back side) for women. The parts with many are different. If the distribution density of the granules of the superabsorbent resin is set on the basis of the portion having a large amount of water absorption, a core region in which the superabsorbent resin is mixed more than necessary is generated, resulting in high costs. On the other hand, when the distribution density of the granules is set based on a portion having a relatively small amount of water absorption, there is a possibility that the water absorption capacity is insufficient at a portion where the water absorption amount is large. Even if the air transport flow of the granules is controlled by opening and closing of a valve or the like, the pulsation and variation of the air current cannot be avoided, and it is difficult to arbitrarily realize a predetermined granule distribution pattern in the absorbent core.

  In view of the above circumstances, an object of the present invention is to freely provide a portion of a water-absorbing core such as a disposable diaper whose water absorption is enhanced with a highly water-absorbent resin.

  In order to solve the above-described problems, the present invention provides a high water-absorbing shape that is preliminarily molded into a predetermined planar shape in a method for manufacturing an absorbent core for sanitary goods by collecting defibrated fibers in a mold and forming a water-absorbing fiber layer. The conductive resin layer is provided so as to overlap with a predetermined position of the water absorbent fiber layer.

Here, the said absorptive core means the package which wrapped the said water absorbing fiber layer and the said highly water absorbing resin layer, and was immersed in the inside from the water-permeable area of the package.
The high water-absorbent resin is a crosslinked body of a hydrophilic linear or branched polymer, and is a porous body having a three-dimensional network structure of cocoon units, and is capable of dissolving in water when contacted with water. However, it is suppressed because there is a cross-linked structure between the molecules, and due to the balance, it becomes a hydrogel in a swollen state in which a certain amount of water is absorbed, and the amount of water absorption per unit mass is larger than that of the water-absorbing fiber layer.

  The predetermined position of the water-absorbing fiber layer and the surface shape of the superabsorbent resin layer can be appropriately determined in advance according to the target age, sex, form of the water-absorbing fiber layer, and the like. Therefore, according to the configuration of the present invention, the superabsorbent resin layer molded in a predetermined plane shape is provided so as to overlap the predetermined position of the water absorbent fiber layer. The part which improved water absorption with the water absorbing resin can be provided freely.

  The sanitary article according to the present invention is worn along the crotch. The water absorbent fiber layer of the absorbent core for sanitary goods is along the crotch, so that one end in the longitudinal direction corresponds to the front side (belly side) or the back side (back side) in the wearing state, and both sides in the short side direction are worn Are provided so as to correspond to both the left and right sides. The water-permeable area of the packaging is formed on the skin contact surface side between the crotch. In this type of absorbent core for sanitary goods, the portion where the water absorption amount of the water absorbent fiber layer increases is present on both sides including the center in the short direction. Moreover, if the water absorption amount of the water absorbent fiber layer is a sanitary article for men, it exists on the front side in the longitudinal direction of the water absorbent fiber layer. If it is a hygiene article for women, it exists over the back side including the center.

  Therefore, the superabsorbent resin layer extends over both sides including the center in the short direction of the superabsorbent fiber layer, and at least one end including the one end side or the center in the longitudinal direction of the superabsorbent fiber layer. If it provides, the water absorption of the part where the water absorption amount of an absorptive core increases can be reliably increased with a highly water absorbent resin. As a result, it is not necessary to mix the granules of the superabsorbent resin in the water absorbent fiber layer, and it is possible to set the distribution density of the granules on the basis of the portion having a relatively small amount of water absorption. The amount used can be reduced.

  As a specific production method, an embodiment in which the superabsorbent resin layer is exposed on the surface of the water absorbent fiber layer or an embodiment in which the superabsorbent fiber layer is buried in the water absorbent fiber layer can be selectively employed.

  If the aspect which exposes the said highly water-absorbing resin layer to the surface of a water-absorbing fiber layer is employ | adopted, the said highly water-absorbing resin layer can be provided so that it may face the water-permeable area of a package directly. If this direct facing is adopted, the water-absorbing resin layer will reach the highly water-absorbent resin layer in a shorter time compared to the mode of being buried in the water-absorbing fiber layer in a shorter time. For this reason, the absorptive core for sanitary goods which absorbs the excreted body fluid earlier is obtained. Further, since the superabsorbent resin layer directly faces the packaging, it is suitable for reducing the thickness of the absorbent core.

  The positioning of the highly water-absorbent resin layer is not particularly limited as long as the position fixing that can withstand the use of sanitary products can be obtained, and adhesion, fusion, entanglement, and the like can be appropriately performed.

  For example, air-transported defibrated fibers are guided to the mold by suction, and the water-absorbing fiber layer is formed, and the water-absorbing fiber layer is maintained in the mold by suction while the highly water-absorbent resin is formed. Adhering the layer to the exposed surface of the water absorbent fiber layer.

  A mold having a suction function is open to the pneumatic transport system of defibrated fibers. For this reason, the water absorbing fiber layer formed in the mold has a surface exposed to the outside of the mold. The predetermined position can be determined on the exposed surface of the water absorbent fiber layer. In other words, the exposed surface can be formed according to the predetermined position.

  If the water-absorbing fiber layer is maintained on the mold by suction, the highly water-absorbing resin layer can be brought into contact with the exposed surface. If the superabsorbent resin layer is bonded to the superabsorbent fiber layer using this, the superabsorbent resin layer can be disposed and temporarily fixed at the same time. This type of water-absorbing fiber layer is prevented from being deformed by packaging. The water-absorbing fiber layer is handled so that the water-absorbing fiber layer does not lose its shape after release until packaging. From this essential manufacturing condition, there is no fear that the water-absorbing fiber layer collapses and the fixing position of the high water-absorbing resin layer shifts during transfer and packaging after bonding. Since temporary fixing of the superabsorbent resin layer is obtained by adhesion, transfer and packaging can be easily performed. After packaging, there is no fear that the fixing position of the highly water-absorbent resin layer is shifted by preventing the water-absorbent fiber layer from being out of shape. For this reason, the highly water-absorbing resin layer is provided so as to overlap a predetermined position of the water-absorbing fiber layer.

  Further, the superabsorbent resin layer can be positioned using packaging.

  For example, a step of guiding defibrated fibers that are pneumatically transported to the mold by suction and forming the water-absorbing fiber layer, and the water-absorbing fiber layer while maintaining the water-absorbing fiber layer in the mold by suction The step of disposing the superabsorbent resin layer on the exposed surface of the substrate, and forming the defibrated fiber that is pneumatically transported by suction while maintaining the relative position of the superabsorbent fiber layer and the superabsorbent resin layer by suction. Leading to a mold, and growing the water absorbent fiber layer around at least the high water absorbent resin layer, and transferring it onto the packaging material while maintaining the relative position of the water absorbent fiber layer and the high water absorbent resin layer. The step of positioning the superabsorbent resin layer at the predetermined position by wrapping the superabsorbent fiber layer and the superabsorbent resin layer with the packaging material can be performed.

  If the water-absorbing fiber layer is maintained in the mold by suction, it is possible to dispose the highly water-absorbing resin layer at a predetermined position determined on the exposed surface. After that, when the water-absorbing fiber layer is grown at least around the superabsorbent resin layer, the superabsorbent resin layer is pressed by packaging so that it does not float off the water-absorbent fiber layer, and the water-absorbing fiber layer portion in the surrounding area absorbs water. It can be positioned in a direction along the fiber layer. Therefore, the superabsorbent resin layer can be positioned at the predetermined position by using the packaging and the surrounding superabsorbent fiber layer portion without fixing the superabsorbent resin layer to the superabsorbent fiber layer.

  Considering thinning of the absorbent core, it is preferable to grow the water absorbent fiber layer only at the periphery thereof at a height not exceeding the high water absorbent resin layer.

  Considering that the superabsorbent fiber layer is temporarily positioned by suction, it is preferable to form a suction surface without holes in the superabsorbent resin layer. When the suction surface is formed, it is difficult for defibrated fibers to accumulate on the suction surface portion while the water-absorbing fiber layer is grown. For this reason, when giving priority to the ease of the growth process and the temporary fixing strength, it is preferable to keep the growth of the water absorbent fiber layer around the highly water absorbent resin.

  The water-absorbing fiber layer can be grown so as to cover the highly water-absorbent resin layer. When the water-absorbing fiber layer is grown in this way, the highly water-absorbing resin layer is buried in the water-absorbing fiber layer. If the water-absorbing fiber layer is formed only around the superabsorbent resin layer, it is necessary to consider that the superabsorbent resin layer does not float during transfer, but the water-absorbing fiber layer covers the superabsorbent resin layer. And there exists an advantage that a highly water-absorbing resin layer does not float easily.

  In addition, as described above, instead of forming the water-absorbing fiber layer first and disposing the high water-absorbing resin layer on the exposed surface, the water-absorbing resin layer is first placed in the mold, A conductive fiber layer can also be formed.

  For example, the high water-absorbing resin layer is disposed at a predetermined position on the bottom surface of the mold, and the defibrated fiber that is pneumatically transported is maintained while maintaining the position of the high water-absorbing resin layer by suction from the bottom surface. Leading to a mold, forming the water-absorbing fiber layer so as to cover the superabsorbent resin layer and its periphery, and maintaining the relative position of the water-absorbing fiber layer and the superabsorbent resin layer on the packaging material And positioning the superabsorbent resin layer by wrapping the superabsorbent fiber layer and the superabsorbent resin layer with the packaging material.

  A superabsorbent resin layer is disposed at a predetermined position on the bottom surface of the mold, and the defibrated fibers that are pneumatically transported are guided to the mold while maintaining the position of the superabsorbent resin layer by suction from the bottom surface. If it makes it, a water absorbing fiber layer can be formed so that a highly water absorbing resin layer and this circumference | surroundings may be covered. That is, there is no need to grow a water absorbent fiber layer around the highly water absorbent resin layer. The point which positions a super absorbent polymer layer in a predetermined position using a package and the surrounding water absorbent fiber layer part is as above-mentioned. Moreover, since the water-absorbing fiber layer and the highly water-absorbing resin layer are formed at the same level from the bottom surface of the mold, the thickness of the absorbent core can be easily reduced.

  In consideration of covering the highly water-absorbing resin layer with the water-absorbing fiber layer, it is preferable to form the water-absorbing fiber layer by suction through the highly water-absorbing resin layer. Instead of sucking the superabsorbent resin layer with the water absorbent fiber layer interposed as described above, the superabsorbent resin layer is sucked directly on the bottom of the mold by suction. Has the advantage of being easy to fix the position. In order to perform suction through the superabsorbent resin layer, for example, the superabsorbent resin layer is formed in a net shape, the vent holes are formed in a dispersed arrangement in the superabsorbent resin layer, or the suction is permeated through the mesh. A highly water-absorbent resin layer can be composed of cloth, nonwoven fabric, or knitted fabric.

  Further, the present invention provides a hygroscopic absorbent core comprising a water absorbent fiber layer formed of defibrated fibers and a highly water absorbent resin. A configuration is employed in which the fiber layer is provided so as to extend to both sides including the center in the short direction and to extend to one end side or at least one end including the center in the longitudinal direction of the water absorbent fiber layer.

  As described above, if the highly water-absorbing resin layer is fixed, the water-absorbing property of the portion where the body fluid of the absorbent core increases can be reliably increased with the highly water-absorbing resin. As a result, it is not necessary to mix the granules of the superabsorbent resin in the water absorbent fiber layer, and it is possible to set the distribution density of the granules on the basis of the portion having a relatively small amount of water absorption. The amount used can be reduced.

Hereinafter, a first embodiment according to the present invention will be described with reference to the accompanying drawings.
As shown in FIGS. 1 and 2, the manufacturing apparatus according to the first embodiment includes a molding die 11 in which a shape pattern of an absorbent core C for sanitary goods (hereinafter simply referred to as an absorbent core C) is formed. The pattern drum device 10, the defibrating machine 20 for defibrating the pulp sheet S 1, the first chamber 21 in which the fibers defibrated by the defibrating machine 20 are transported by air, and the fiber layer formed in the first chamber 21. A sheet distribution device 30 that disposes the superabsorbent resin layer C2 on C1 and a second chamber 22 in which the fibers defibrated by the defibrator 20 are pneumatically transported.

  As shown in a development view in FIG. 3A, the sanitary article according to the first embodiment is a paper diaper. The absorptive core C is provided in the part along the crotch part of sanitary goods. As schematically illustrated in FIG. 3B, the absorbent core C includes a fiber layer C1, a highly water-absorbent resin layer C2, and the like, a water-permeable sheet S3 that wraps them, and a further outer portion of the water-permeable sheet S3. A water-impermeable undercover 103 and a water-permeable top cover 104. That is, the absorbent core C uses the water-permeable sheet S3, the water-impermeable under cover 103, and the water-permeable top cover 104 as packaging materials. The water permeable area of the packaging is composed of a portion where the water permeable top cover 104 and the water permeable sheet S3 overlap. The impermeable undercover 103 is fixed so as to be bridged between the stomach side portion 101 and the back side portion 102 of the paper diaper.

  As shown in FIG. 1, the pattern drum apparatus 10 has a plurality of molds 11 arranged in the circumferential direction on the outer peripheral surface. Each mold 11 circulates from the upstream side to the downstream side as the pattern drum device 10 rotates in one direction.

(First step)
As shown in FIG. 2A, the bottom surface of the mold 11 is a mesh. As shown in FIG. 1, while the mold 11 passes through the first chamber 21, suction is performed from the rotation center axis side of the pattern drum device 10 (arrow np <b> 1 in the drawing), and the fibers are pneumatically transported. As shown in FIG. 2 (a), it is guided to the mold 11 and accumulated in this mold. As a result, a fiber layer C 1 having a predetermined planar shape and thickness is formed in the mold 11 in the first chamber 21. The formed fiber layer C <b> 1 is formed by accumulating fibers that are pneumatically transported, and thus has a cotton shape and water absorption.

  In the first step, for example, the technology of the core generator disclosed in Japanese Patent Laid-Open No. 2003-199790 can be employed.

(Second step)
As shown in FIG. 1, the rotation of the pattern drum device 10 further proceeds, and the forming die 11 on which the fiber layer C <b> 1 is formed is carried out of the first chamber 21, and the diameter of the sheet supply roller 31 of the sheet distribution device 30. The sheet is conveyed into the second chamber 22 through a position facing the direction. During this time, suction in the mold 11 is continued (arrow line np1 in the figure), whereby the position of the fiber layer C1 with respect to the mold 11 is maintained.

  The sheet distribution device 30 manufactures the highly water-absorbing resin layer C2 by previously forming the sheet S2 made of the highly water-absorbing resin into a predetermined surface shape, and holds it on the sheet supply roller 31 as shown in FIG. The superabsorbent resin layer C2 thus arranged is arranged at a predetermined position on the exposed surface of the passing fiber layer C1. The positions of the fiber layer C1 and the highly water-absorbent resin layer C2 with respect to the mold 11 are maintained by suction (arrow np1 in the figure). Here, the position of the highly water-absorbing resin layer C2 can be firmly maintained by adopting a process in which the highly water-absorbing resin layer C2 is bonded to, fused to, or entangled with the fiber layer C1. At this time, these position fixing steps can be employed in place of the above-described position maintenance by suction or in combination as appropriate.

  As the sheet S2, for example, a substrate sheet such as a nonwoven fabric or a film coated with a highly water absorbent resin, a nonwoven fabric made of a highly water absorbent resin, or the like can be used. The sheet distribution device 30 is cut out from the sheet S2 into a predetermined shape with a cutter to form the highly water absorbent resin layer C2.

  The sheet supply roller 31 can freely change the arrangement position with respect to the exposed surface of the fiber layer C1.

  In the second step, for example, as shown in FIG. 4 (a), the superabsorbent resin layer C2 extends over both sides including the center in the short direction of the fiber layer C1, and one end side in the longitudinal direction of the fiber layer C1. Can only be placed in According to this example, by using one end side in the longitudinal direction of the absorbent core C as a front side for men's sanitary goods, it is possible to reliably increase the absorbability of the portion with the largest water absorption.

  As another example, as shown in FIG. 4B, the superabsorbent resin layer C2 has both ends including the center in the short direction of the fiber layer C1, and both ends including the center in the longitudinal direction of the fiber layer C1. It can be arranged to cover the side. According to this another example, the absorbability of the portion with the largest water absorption can be reliably increased by using it especially for sanitary goods for women.

  As another example, as shown in FIG. 4 (c), the superabsorbent resin layer C2 extends over both sides including the center in the short direction of the fiber layer C1, and both ends in the longitudinal direction of the fiber layer C1. A plurality of sheets can be arranged separately. According to this other example, by using it for men's sanitary goods, the water absorption of urine can be reliably increased on the front side, and the water absorption of soft stool can be reliably increased on the rear side.

  Instead of the sheet supply roller 31, the technology of a re-pitch drum device and a re-pitch turn device disclosed in Japanese Patent Laid-Open No. 2003-199790 can also be employed.

  The superabsorbent resin layer C2 is disposed on the exposed surface of the fiber layer C1 in the mold 11. After this arrangement, the fiber layer C1 is exposed around the superabsorbent resin layer C2. For this reason, if the defibrated fiber is further sucked, the fiber layer can be grown around the superabsorbent resin layer C2.

(Third step)
That is, as shown in FIG. 1, the rotation of the pattern drum device 10 proceeds, and the mold 11 in which the fiber layer C <b> 1 and the superabsorbent resin layer C <b> 2 are maintained enters the second chamber 22. While the molding die 11 passes through the second chamber 22, as shown in FIG. 2 (c), the fibers that are pneumatically transported are guided to the molding die 11 by suction that permeates the high water absorbent resin layer C2. (Arrow np1 in the figure), accumulated in this mold. As a result, the growth layer C3 is formed in a cotton shape so as to cover the superabsorbent resin layer C2 and to cover the fiber layer C1 around the superabsorbent resin layer. The growth layer C3 has water absorbency like the fiber layer C1. That is, the fiber layer C1 and the growth layer C3 form a water absorbent fiber layer of the absorbent core C as a whole (hereinafter, when the water absorbent fiber layer according to the first embodiment is shown, the water absorbent fiber layer). C1, C3).

  Suction through the highly water-absorbent resin layer C2 can be realized by forming the highly water-absorbent resin layer C2 on a rough cloth, nonwoven fabric, mesh or the like having air permeability capable of obtaining a predetermined suction force. The positions of the fiber layer C1, the superabsorbent resin layer C2, and the growth layer C3 with respect to the mold 11 are maintained by the suction np1.

  In the third step, for example, the technology of the core generator disclosed in Japanese Patent Laid-Open No. 2003-199790 can be employed.

  The growth layer C3 is mixed with granules of a superabsorbent resin. The granules of the superabsorbent resin are mixed with the defibrated fibers that are pneumatically transported in the supply line that merges from the supply source 40 through the duct 41 to the second chamber 22. Thus, it is also possible to mix the superabsorbent resin granules in the fiber layer C1 and the growth layer C3 as necessary. Since the fiber layer C1 is formed first, it is possible to prevent the granules from being sucked from the suction holes of the mold 11 or clogging the suction holes.

  High water-absorbing resins include starch-acrylic acid graft, polyacrylate, polyvinyl alcohol, vinyl acetate-acrylate, isobutylene-maleic acid, and poly N vinylacetamide. Depending on the type, the type of hydrophilic resin to be a trunk and the crosslinking density are selected. For example, a water absorption amount of 10 g or more per 1 g of resin can be adopted. In the case of the absorbent core for sanitary goods, since the body fluid contains a large amount of electrolyte, it is preferable to use a resin having a large number of hydrophilic groups as a trunk, and in particular, a polyacrylate-based one is also preferable in terms of cost. The superabsorbent resin layer C2 and the granules appropriately mixed in the superabsorbent fiber layers C1 and C3 can be the same or different superabsorbent resins.

  When the pattern drum device 10 further rotates and the mold 11 exits the second chamber, excess fibers are dropped by the scarfing roller 12. As a result, the molding of the water absorbent fiber layers C1 and C3 formed of defibrated fibers is completed. The superabsorbent resin layer C2 is buried so as to extend on both sides including the center in the short direction of the water absorbent fiber layers C1 and C3 and on both sides including the center in the longitudinal direction of the water absorbent fiber layers C1 and C3. . While excess fibers are dropped by the scarfing roller 12, the position of the growth layer C3 and the like with respect to the mold 11 is continuously maintained by suction (arrow np1 in the figure).

(4th process)
If the rotation of the pattern drum device 10 further proceeds while the water absorbing fiber layers C1 and C3 and the high water absorbing resin layer C2 are maintained in the mold 11 by the suction np1, the mold 11 eventually reaches the transfer roller device 13 in diameter. Reach the position opposite to the direction. At this position, the mold 11 is switched and connected from the negative pressure system to the positive pressure system. For this reason, the growth layer C3 and the like are released from one another by being given a positive pressure from the bottom surface of the mold 11 (arrow pp in the figure). At this time, the superabsorbent resin layer C2 is positioned so as not to move in the direction along the fiber layer C1 by the growth layer C3 around the superabsorbent resin layer C2. In addition, since the growth layer C3 overlaps the superabsorbent resin layer C2, the superabsorbent resin layer C2 does not float from the fiber layer C1, and the positioning is not lost. Therefore, the relative positions of the layers C1 to C3 can be maintained.

  In particular, if the water-absorbing fiber layers C1 and C3 in which the superabsorbent resin layer C2 is buried are pushed out from the bottom surface of the mold 11, the superabsorbent resin layer C2 is pushed out together with the fiber layer C1 toward the growth layer C3. . If pushed in this direction, there is an advantage that the layers C1 and C2 are easily released so as not to be separated. That is, the growth layer C3 comes out of the mold 11 first. For this reason, when the mold is released by suction from the outside of the mold 11 or free fall under a non-pressure condition, the growth layer C3 is separated from the fiber layer C1 and the superabsorbent resin layer C2 remaining in the mold 11. Easy to do. When the superabsorbent resin layer C2 is extruded toward the growth layer C3 together with the fiber layer C1, it is difficult to separate.

  Note that, regardless of the positive pressure, as long as the relative positions of the water-absorbing fiber layers C1, C3 and the highly water-absorbent resin layer C2 are maintained, free fall under no-pressure condition or suction from the outside of the mold 11 It can also be released.

  The released water-absorbing fiber layers C1, C3 and the like are quickly sucked into the holding portion of the transfer roller device 13 (arrow np2 in the figure). During this time, the suction pressure, the pressure distribution, etc. are adjusted so that the relative positions of the water absorbent fiber layers C1, C3 and the highly water absorbent resin layer C2 are maintained. The transfer roller device 13 appropriately adjusts the conveyance interval of the water absorbent fiber layers C1, C3, etc., and transfers the water absorbent fiber layers C1, C3, etc. onto the permeable sheet S3 to be unwound.

  For the transfer roller device 13 shown in FIG. 1, the technology of the re-pitch drum device and the re-pitch turn device disclosed in Japanese Patent Laid-Open No. 2003-199790 can be employed. The transfer roller device 13 may be omitted, and the water absorbent fiber layers C1, C3 and the like may be transferred from the pattern drum device 10 onto the water permeable sheet S3.

  After being transferred onto the water permeable sheet S3, both sides in the width direction of the water permeable sheet S3 are joined so as to be folded on the upper surfaces of the water absorbent fiber layers C1 and C3 as shown in FIG. After that, although not shown in the figure, from the outside wrapped with the water-permeable sheet S3, the paper is wrapped so as to be sandwiched between the water-impermeable under cover 103 and the water-permeable top cover 104 so as to surround the periphery of the water absorbent fiber layers C1 and C3. Sealed. Thereby, the absorptive core C is completed. Thereafter, the absorbent core C is cut into individual pieces. The packaging made of the water permeable sheet S3, the water permeable under cover 103, and the water permeable top cover 104 prevents the water absorbing fiber layers C1 and C3 from being deformed. For this reason, there is no fear that the position of the highly water-absorbent resin layer C2 is out of shape. The positioning of the superabsorbent resin layer C2 may be performed so as not to deviate from a desired range during use of the sanitary product.

  In addition, when forming the stomach side part 101 and the back side part 102 of a paper diaper using the same waterproof sheet, the functional part equivalent to the impermeable undercover 103 can be formed in the waterproof sheet. In this case, the water-impermeable under cover 103 and the water-permeable top cover 104 can be omitted, and the absorbent core packaging can be configured only by the water-permeable sheet S3. As the water permeable sheet S3, any sheet may be used as long as it has a strength to keep the shape of the water absorbent fiber layers C1 and C3 within a predetermined range. For example, a tissue or a nonwoven fabric can be used.

  In the first embodiment described above, the superabsorbent resin layer C2 molded in a predetermined plane shape in advance is overlapped with a predetermined position of the water absorbent fiber layers C1 and C3 formed in a predetermined three-dimensional shape by the molding die 11. Since it is provided, the absorbent core C such as a paper diaper can be freely provided with a portion having increased water absorption with a highly water absorbent resin.

  In the first embodiment described above, as illustrated in FIG. 4, the superabsorbent resin layer C2 extends over both sides including the center in the short direction of the superabsorbent fiber layers C1 and C3, and the superabsorbent fiber layer C1. , C3 is arranged so as to extend to at least one end side including the one end side or the center in the longitudinal direction of C3, so that the water absorption of the portion where the water absorption amount of the absorbent core C increases can be reliably increased by the superabsorbent resin layer C2. it can. As a result, it is possible to omit the mixing of the highly water-absorbent resin granules in the water-absorbing fiber layer C1, and to set the distribution density of the granules on the basis of the relatively small amount of water absorption in the growth layer C3. The amount of superabsorbent resin used can be reduced.

  Moreover, since the above-mentioned 1st Embodiment will be in the state which buried the highly water-absorbent resin layer C2 in the water-absorbent fiber layers C1, C3 after finishing the third step, The fiber layers C1 and C3 can prevent the superabsorbent resin layer C2 from being lifted or displaced.

  Further, in the first embodiment described above, after finishing the fourth step, the water-permeable sheet S3, the water-impermeable undercover 103, and the like can be obtained without fixing the superabsorbent resin layer C2 to the water-absorbent fiber layers C1 and C3. The superabsorbent resin layer can be positioned at a predetermined position by using the package and the surrounding water absorbent fiber layer C3. For this reason, in the first embodiment, it is not necessary to bond, fuse, or entangle the superabsorbent resin layer C2 to the fiber layer C1, and the manufacturing process can be simplified.

  In the first embodiment described above, the first step is performed in the first chamber 21 in which the defibrated fibers are pneumatically transported, and the third step is performed in the second chamber 22 in which the defibrated fibers are pneumatically transported. The plurality of molds 11 are sequentially conveyed from the first process to the fourth process, and the second process is performed outside the first chamber 21 and the second chamber 22. For this reason, the fiber layer of the molding die 11 outside the first chamber 21 and the second chamber 22 is simultaneously drawn with the suction of the defibrated fibers in the molding die 11 in the first chamber 21 and the second chamber 22. The second step can be performed by superimposing the superabsorbent resin layer C2 on C1 without being disturbed by the air transport flow of the defibrated fibers. Therefore, compared with the case where all the processes are performed in one chamber, the above-described first embodiment can increase the manufacturing efficiency by sending the molding die to each process one after another. It should be noted that the first chamber 21 and the second chamber 22 are under conditions in which leakage of the air transport flow and the flow of outside air are prevented so as not to shift the position of the superabsorbent resin layer C2 whose position is maintained by suction. It is in.

  Hereinafter, other embodiments will be described. In the following description, only differences from the first embodiment will be described, and the same names are used for items that are considered to be the same, and descriptions thereof are omitted.

  As shown in FIG. 5, the water absorbent fiber layer C1 'according to the second embodiment is formed so as to cover one surface of the highly water absorbent resin layer C2 and the periphery of the highly water absorbent resin layer C2. The absorbent core according to the second embodiment can be made thin because the water absorbent fiber layer C1 'is flush with the highly water absorbent resin layer C2.

  As shown in FIG. 6, in the manufacturing method according to the second embodiment, a highly water-absorbing resin layer C2 is disposed at a predetermined position on the bottom surface of the mold 11 with the sheet supply roller 31, and the high water-absorbing property is obtained by suction from the bottom surface. The difference is that the defibrated fibers that are pneumatically transported are guided to the mold 11 while maintaining the position of the resin layer C2.

  The defibrated fibers are guided to the mold 11 by suction that has passed through the superabsorbent resin layer C2. For this reason, the water absorbent fiber layer C1 'is formed so as to cover the highly water absorbent resin layer C2. Further, the highly water-absorbing resin layer C <b> 2 has a surface shape that is slightly smaller than the bottom surface of the mold 11. Therefore, the water absorbent fiber layer C1 'is formed so as to cover the periphery of the highly water absorbent resin layer C2, as shown in FIGS. As a result, the water absorbent fiber layer C <b> 1 ′ and the highly water absorbent resin layer C <b> 2 are formed to be flush with the bottom surface of the mold 11.

  2nd Embodiment does not have the effort to grow a fiber layer in the circumference | surroundings of the super absorbent polymer layer C2 by another process like 1st Embodiment. In addition, when releasing the mold 11 by applying a positive pressure from the bottom surface, the superabsorbent fiber layer C1 ′ is pressed against the superabsorbent fiber layer C1 ′, so that the superabsorbent fiber layer C1 ′ and the superabsorbent resin layer are pressed. C2 is difficult to separate, and relative position shift can be prevented.

  As shown in FIG. 7, the absorbent core according to the third embodiment is different in that the superabsorbent resin layer C2 is provided so as to directly face the water-permeable area of the package. For this reason, the absorptive core which concerns on 3rd Embodiment can absorb the excreted body fluid earlier.

  In order to obtain the absorbent core according to the third embodiment, one surface of the highly water absorbent resin layer C2 is exposed from the water absorbent fiber layer C1 '. For example, the water absorbent fiber layer C1 'can be formed as in the second embodiment.

  Moreover, when utilizing 1st Embodiment, one surface of the high water absorption resin layer C2 can be exposed by forming a growth layer only around the high water absorption resin layer C2. In this case, since it is not necessary to cover the highly water-absorbent resin layer C2 with the growth layer, a suction surface without holes can be appropriately formed in the highly water-absorbent resin layer C2. If the suction surface is formed on the highly water-absorbent resin layer C2, temporary fixing of the highly water-absorbent resin layer C2 by suction can be obtained more firmly.

  As described above, the water absorbent fiber layer C1 ′ is formed so that the highly water absorbent resin layer C2 is exposed, and the arrangement of the water impermeable under cover 103 and the water permeable top cover 104 is turned upside down as shown in FIG. When wrapped, the highly water-absorbent resin layer C2 can directly face the water-permeable area of the packaging composed of the water-permeable sheet S3 and the water-permeable top cover 104.

  In the first to third embodiments described above, the superabsorbent resin layer is temporarily fixed to the water absorbent fiber layer by suction until packaging is completed, but it can also be positioned by adhesion to the exposed surface of the water absorbent fiber layer. .

  For example, as shown in FIG. 8, in the fourth embodiment, a water absorbent fiber layer C <b> 1 ″ that fills the mold 11 is formed. One surface of the superabsorbent resin layer C2 is an adhesive surface to which the adhesive a is applied. The highly water-absorbing resin layer C2 is bonded to the exposed surface of the water-absorbing fiber layer C1 ″ held by the sheet supply roller 31 by suction on the mold 11 and thereby bonded. For this reason, 4th Embodiment can perform arrangement | positioning and temporary fixation of the highly water-absorbent resin layer C2 simultaneously.

  For example, as in the example of FIGS. 3B and 7, unless the adhesive surface side of the highly water-absorbent resin layer C <b> 2 is directed to the water-permeable regions S <b> 3 and 104 of the packaging, The property can be reliably improved by the highly water-absorbent resin layer C2. As long as this is the case, the adhesive a can be applied to the entire surface of the superabsorbent resin layer C2.

  As shown in FIG. 8, it is preferable to disperse and apply the adhesive a on one surface of the superabsorbent resin layer C2. The non-application area | region of the adhesive agent a can be provided with the osmosis | permeation path | route from the water-permeable area of a package to the super absorbent polymer layer C2. In this case, the adhesive surface side of the highly water-absorbent resin layer C2 can be directed to the water-permeable area of the packaging.

  For example, in the example of FIG. 5, by providing the non-application area as described above, a permeation path including the water-absorbing fiber layer C1 ′ and the non-application area is provided from the water-permeable areas S3 and 104 of the packaging. The water absorption of the part which becomes can be raised with the high water absorption resin layer C2.

The conceptual diagram which shows the whole structure of the manufacturing apparatus of the absorptive core for sanitary goods which concerns on 1st Embodiment. a is a principal process diagram for forming the fiber layer according to the first embodiment, b is a principal process diagram for arranging the superabsorbent resin layer according to the first embodiment, and c is a growth layer according to the first embodiment. Main part process diagram to be formed a is a development view of a sanitary article provided with the absorbent core according to the first embodiment, and b is a schematic view simply showing a cut surface of the line bb of a. a is a top view of an absorptive core which shows the example of arrangement of a superabsorbent resin layer in a 1st embodiment, b is a top view of an absorptive core which shows the example of arrangement of another superabsorbent resin layer, c is other high The top view of the absorptive core which shows the example of arrangement | positioning of a water absorbing resin layer The schematic diagram which simplifiedly displayed the absorptive core for sanitary goods which concerns on 2nd Embodiment by the same cut surface as FIG.3 (b). a is a main process diagram for disposing a superabsorbent resin layer according to the second embodiment, and b is a main process diagram for forming a water absorbent fiber layer after the a. The schematic diagram which simplifiedly displayed the absorptive core for sanitary goods which concerns on 3rd Embodiment by the same cut surface as FIG.3 (b). Process drawing of a main part for adhering the superabsorbent resin layer of the absorbent core for sanitary goods according to the fourth embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Pattern drum apparatus 11 Mold 20 Disentanglement machine 21 1st chamber 22 2nd chamber 30 Sheet distribution apparatus 31 Sheet supply roller 103 Water-impermeable undercover 104 Water-permeable top cover C Absorbent core C1 Fiber layer C1 ', C1'' Water absorbent fiber layer C2 Super water absorbent resin layer C3 Growth layer S3 Water permeable sheet

Claims (7)

  In the method for manufacturing an absorbent core for hygiene articles in which defibrated fibers are collected in a mold to form a water-absorbing fiber layer, a superabsorbent resin layer molded in advance into a predetermined surface shape is used as a predetermined in the water-absorbing fiber layer. A method for producing an absorbent core for sanitary goods, characterized by being provided so as to overlap with a position.   The superabsorbent resin layer is provided so as to extend on both sides including the center in the short side direction of the water absorbent fiber layer, and on at least one end side including the one end side or the center in the longitudinal direction of the water absorbent fiber layer. The manufacturing method of the absorptive core for sanitary goods of Claim 1 characterized by these.   The method for producing an absorbent core for sanitary goods according to claim 2, wherein the superabsorbent resin layer is provided so as to directly face the water-permeable area of the package.   Introducing air-delivered defibrated fibers to the mold by suction and forming the water-absorbing fiber layer, and maintaining the water-absorbing fiber layer in the mold by suction, The method for producing an absorbent core for sanitary goods according to any one of claims 1 to 3, wherein the step of adhering to the exposed surface of the water absorbent fiber layer is performed.   Introducing air-delivered defibrated fibers to the mold by suction and forming the water-absorbent fiber layer, and exposing the water-absorbent fiber layer while maintaining the water-absorbent fiber layer in the mold by suction The step of disposing the superabsorbent resin layer on the surface, and maintaining the relative position of the superabsorbent fiber layer and the superabsorbent resin layer by suction, the defibrated fiber that is pneumatically transported to the mold by suction Guiding, growing the water-absorbing fiber layer so as to cover the superabsorbent resin layer and its surroundings, and transferring the water-absorbing fiber layer onto the packaging material while maintaining the relative positions of the water-absorbing fiber layer and the superabsorbent resin layer And the step of positioning the superabsorbent resin layer at the predetermined position by wrapping the superabsorbent fiber layer and the superabsorbent resin layer with the packaging material. Of the absorbent core for sanitary goods according to any one of Production method.   The superabsorbent resin layer is disposed at a predetermined position on the bottom surface of the molding die, and the defibrated fiber that is pneumatically transported is maintained in the molding die while maintaining the position of the superabsorbent resin layer by suction from the bottom surface. A step of forming the water-absorbent fiber layer so as to cover the superabsorbent resin layer and its surroundings, and transferring the water-absorbent fiber layer onto the packaging material while maintaining the relative positions of the water-absorbent fiber layer and the superabsorbent resin layer; And the step of positioning the superabsorbent resin layer at the predetermined position by wrapping the superabsorbent fiber layer and the superabsorbent resin layer with the packaging material. The manufacturing method of the absorptive core for sanitary goods as described in any one of these.   In the absorbent core for sanitary goods including a water absorbent fiber layer formed of defibrated fibers and a highly water absorbent resin, the super absorbent polymer layer formed into a planar shape is a short direction of the water absorbent fiber layer. The absorbent core for hygiene articles is provided so as to extend over both sides including the center and at least one end including the center in the longitudinal direction of the water absorbent fiber layer.

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