WO2009119859A1 - Fiber integration device for absorber, and absorber - Google Patents

Abstract

A fiber integration device capable of forming an absorber that can stably the reduce weight thereof. The fiber integration device for an absorber has a rotary drum equipped with a means for sucking particulates into the inner side, and a plurality of fiber integration supports (3) disposed on the circumferential surface of the rotary drum, integrating the particulates supplied to the inside of a chamber by the sucking means on an absorber forming region (15) of the fiber integration supports (3) to form the absorber. The absorber forming region (15) has a porous region (5) and a non-porous region (6), which is disposed at a peripheral region of the absorber forming region (15) to be surrounded by the porous region (5).

Description

 Textbook Absorber fiber stacking device and absorber Technical Field

 The present invention relates to an absorbent stacking device. In particular, the present invention relates to a fiber stacking apparatus that can form an absorbent body that can be stably lowered in weight, and an absorbent body manufactured by the fiber stacking apparatus. Background art

 Absorbents for absorbing urine, feces, menstrual blood, etc. are used for absorbent articles such as disposable diapers, sanitary napkins, panty liners, etc., and the absorbent is molded with powdered pulp or absorbent polymer. Has been. As an apparatus for manufacturing such an absorbent body, generally, a rotating drum, a vacuum suction section in the rotating drum, and a powdered pulp placed on an air flow, an absorber disposed on the outer peripheral surface of the rotating drum is used. A fiber stacking apparatus including a supply means for supplying the fiber stacking cavity is known (Japanese Patent Laid-Open No. Sho 60-0-2 3 6 6 4 6). A suction hole communicating with the vacuum suction part is provided on the bottom surface of the stacking cavity. The pile fiber cavity in such a configuration circulates between the supply means and the vacuum suction part, and at this time, the dust pulp is piled inside. Absorbents piled inside the cavity are separated from the supply means and the vacuum suction section, and transferred to a conveyor (Japanese Patent Laid-Open No. Sho 60-236066).

In order to adjust the amount of fiber piled up in the absorbent body constituting the absorbent article, a device for adjusting by disposing a non-breathable part by providing a sealing agent at the bottom of the cavity (Japanese Patent Laid-Open No. 5-200) 0 6 No. 2) or piled up with the three-dimensional structure of the porous body at the bottom of the cavity, or the cavity opening A 3D shape forming part is attached to the bottom of the stacking fiber cavity so that it becomes convex on the side, and after excess powder is piled up, the excess powder is removed with a tool for scraping off. Kaisho 6 0 — 2 3 6 6 4 6) is known. Disclosure of the invention

 However, in the fiber stacking apparatus described in Japanese Patent Application Laid-Open No. Sho 60-0 2 3 6 6 46, the shape of the stacked fiber is disturbed at the time of shaving off, and the shape of the stacked fiber is not stable. When there is a large amount, there is a sense of incongruity during use, and when the amount of pile is small, the absorbency decreases and the possibility of causing external leakage increases. In the fiber stacking apparatus described in Japanese Patent Laid-Open No. 5-200 062, if the sealant deteriorates and falls off the support, the desired absorbent cannot be formed, and the dropped sealant becomes a foreign matter. Causes problems when used. Thus, until now, there has been no known effective method for stably adjusting the amount of piled fiber in the absorbent body constituting the absorbent article. Therefore, the present invention stably reduces the basis weight. An object of the present invention is to provide a fiber stacking apparatus capable of forming a possible absorbent body.

 As a result of intensive studies in view of such circumstances, the present inventors have, as a piled fiber support forming an absorbent body, a perforated region and a non-porous region, and the non-porous region is an absorbent-forming region. The present invention has been completed by discovering that an absorbent body of an absorbent article that can be stably reduced in weight can be formed by using a support disposed so as to be surrounded by the perforated region in the peripheral region of It was.

That is, (1) The present invention includes a rotating drum provided with a means for sucking on the inner surface side, and a plurality of fiber stacking supports disposed on the outer peripheral surface of the rotating drum, The granular material supplied to the An absorbent stacking device for forming an absorbent by stacking on an absorbent forming region of a stacking support, the absorbent forming region having a perforated region and a non-porous region, and The non-porous region is provided in the fiber stacking device, wherein the non-porous region is arranged in a peripheral region of the absorbent body forming region so as to be surrounded by the perforated region.

 (2) The present invention provides the fiber stacking apparatus according to (1), wherein the non-porous region is disposed at a position of 5 mm to 15 mm from the outer edge of the absorber forming region.

 (3) The present invention provides the fiber stacking apparatus according to (1) or (2), wherein an interval between two adjacent non-porous regions is 5 mm to 20 mm.

 (4) The present invention provides the fiber stacking apparatus according to any one of (1) to (3), wherein the fiber stacking support body further includes a recess for forming an absorbent body with respect to an outer peripheral surface of the rotating drum. provide.

 (5) The present invention provides the fiber stacking apparatus according to any one of (1) to (4), wherein the perforated region is formed by etching.

 (6) The present invention is such that a low porosity area having a lower porosity than the perforated area surrounds the non-porous area, and at least a part thereof is in contact with the perforated area. The fiber stacking apparatus according to any one of (1) to (5), further arranged.

 (7) The present invention provides the fiber stacking apparatus according to any one of (1) to (6), wherein a thickness of the fiber stack support is uniform.

 (8) The present invention is an absorbent body having a region in which the basis weight of the powder and granule is different from each other, and a high basis weight region having a high basis weight is disposed in the central region of the absorber, compared to a high basis weight region. A low basis weight region having a low basis weight is disposed in a peripheral region of the absorber so as to be surrounded by the high basis weight region.

(9) The present invention is described in (8), wherein the basis weight of the high basis weight region is 2500 g / m ² or less and 1.5 times or more the basis weight of the low basis weight region. Provide an absorber.

 (10) The present invention provides the absorbent body according to (8) or (9), wherein the low basis weight region is disposed at a position of 5 mm to 15 mm from the outer edge of the absorbent body.

 (11) The present invention provides the absorbent body according to any one of (8) to (10), wherein an interval between two adjacent low basis weight regions is 5 mm to 20 mm.

 (12) In the present invention, the region having a basis weight between the basis weight of the high basis weight region and the basis weight of the low basis weight region is so small that the region having the basis weight surrounds the low basis weight region. And (8) to (11) The absorbent body according to any one of (8) to (11), which is further arranged so that a part thereof is in contact with the high basis weight region.

 According to the present invention, it is possible to dispose a low basis weight region surrounded by a high basis weight region in the peripheral region of the absorber, thereby making it possible to maintain the rigidity of the absorber, and the absorber constituent material It is possible to reduce the use of resources and save resources and reduce costs.

 In addition, by further arranging an area having a basis weight between the basis weight of the high basis weight area and the basis weight of the low basis weight area so as to surround the low basis weight area, The level difference with the basis weight area can be reduced, the discomfort when the absorbent article is attached can be reduced, and deformation due to the rigidity of the absorbent body can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic partial side view of a fiber stacking apparatus of the present invention.

 FIG. 2 is a perspective view of the rotary drum in FIG. 1 and the stacking fiber support disposed on the drum.

 FIG. 3 is a plan view showing one embodiment of the fiber stack support according to the present invention.

And A-A 'sectional view thereof. (A) to (c) of FIG. 4 are plan views showing one embodiment of the absorbent body of the present invention.

 FIG. 5 is a cross-sectional view taken along line AA ′ in FIG.

 FIG. 6 is a plan view showing one embodiment of the absorbent body of the present invention. FIG. 7 is a cross-sectional view taken along the line A—A ′ of FIG. BEST MODE FOR CARRYING OUT THE INVENTION

 Hereinafter, the present invention will be described with reference to the drawings, but the present invention is not limited to those shown in the drawings. FIG. 1 is a schematic partial side view of the fiber stacking apparatus of the present invention, and FIG. 2 is a perspective view of the rotary drum in FIG. 1 and the fiber stacking support body disposed on the rotating drum. FIG. 3 is a plan view showing one embodiment of the stacking fiber support according to the present invention, and a sectional view taken along the line AA ′. (A)-(c) of FIG. 4 is a top view which shows one embodiment of the absorber of this invention. FIG. 5 is a cross-sectional view taken along the line A—A ′ in FIG. FIG. 6 is a plan view showing one embodiment of an absorbent body according to the present invention. Fig. 7 is a cross-sectional view taken along line AA in Fig. 6.

 As shown in FIG. 1, the absorbent fiber stacking device 13 of the present invention comprises an absorbent material constituting powder H powder, a crusher 1, and a powdered absorbent material (powder and granule).

1 2) A chamber 14 that carries the air flow on the air flow, a rotating drum 2 having means for sucking on the inner surface side, a pile support 3 that receives the powder and forms an absorbent, and And a means for delivering the absorbed material to the conveyor 4 for conveyance. The formed absorber is released from the suction in the rotating drum 2 when transferred to the conveyor 4 and transferred onto the conveyor 4. As shown in FIG. 2, a plurality of stacked fiber supports 3 are arranged in a shape matching the outer peripheral curved surface of the rotating drum 2, and each stacked fiber support 3 forms one absorbent body. In the fiber stacking apparatus of the present invention, if necessary, supply means for supplying other additives such as a heat sealing material, and fiber stacking support Means may be provided for thermally fusing and thermally fusing the powder particles laminated on the body 3.

 FIG. 3 is a plan view showing one embodiment of the stacking fiber support according to the present invention, and a sectional view taken along the line AA ′.

 The fiber stack support 3 according to the present invention includes a porous region 5 and a non-porous region 6 in a region where an absorber is to be formed on the support (hereinafter referred to as an “absorber forming region”). The non-porous region 6 is disposed in the peripheral region of the absorbent body forming region 15 so as to be surrounded by the perforated region 5. In the present specification, the “peripheral region” refers to a region around the absorber forming region 15 with respect to the central region of the absorber that comes into contact with the excretion part when the absorbent article is used. means. The outer shape of the absorbent body forming region 15 is the same shape as one absorbent body of the absorbent material, and may be any of a bowl shape, an oval shape, a rectangular shape, and the like. When the absorbent article is, for example, a daytime sanitary napkin, the overall dimension of the outer shape of the absorbent body forming region is preferably 1550 to 230 mm in the longitudinal direction and 50 to 90 mm in the short direction. Is preferred. The perforated region 5 has a hole penetrating from the front surface to the back surface of the fiber stack support 3. The hole has a predetermined hole diameter. The pore diameter is determined by the length of the powder and the like, but is preferably in the range of 0.1 to 1.0 mm. If the hole diameter is less than 0.1 mm, the powder is likely to clog as the power required for suction increases.If the hole diameter exceeds 1.0 mm, the powder will pass through the hole, and the yield of the absorber will be reduced. It is not preferable because it causes a decline.

 The holes are usually arranged in a staggered pattern on the support with a pitch of 0.2 to 3.0 mm. The minimum width of the rib portion formed between the holes is usually 0.1 to 2.0 mm.

Perforation ratio of the perforated region 5, that is, the ratio of the area of the perforated region 5 to the total area of the absorber forming region 15 (opening ratio (%)) ([(perforated region surface Product) / (area of absorber-forming region)〗 X 1 0 0) is preferably 6 to 60%, particularly preferably 20 to 60%. If the open area ratio is less than 6%, the fiber accumulation efficiency is poor and the productivity is lowered, and if it exceeds 60%, the minimum width of the rib part is too narrow and it is difficult to produce a perforated region in the fiber support 3 At the same time, the rib portion of the support is easily broken, which is not preferable.

 The thickness of the pile support 3 is preferably uniform, and is usually in the range of 0.05 to 5.0 mm. This is because when the thickness of the support is uniform, uneven fiber stacking is eliminated, the absorbent body is stably peeled off from the stack support during transport, and high reproducibility of the molded product is obtained.

 The ratio of the maximum hole diameter to the thickness of the pile support 3 ((maximum hole diameter) / (thickness)) is preferably in the range of 0.02 to 10. If it is less than 0.02, the loss of suction pressure increases, and the productivity is lowered. If it exceeds 10, the strength of the rib portion is lowered and the durability is lowered, which is not preferable. '

 The pore diameter, the open area ratio, and the like are appropriately selected depending on the components of the granular material, the thickness of the laminated granular material, and the like.

 The non-porous region 6 may be a closed figure surrounded by the perforated region 5 such as, for example, a circle, an elliptical system, a rectangle, a square, or a star. The minimum width of the non-porous region 6 should be able to produce a basis weight difference between the granular material 1 2 stacked in the non-porous region 6 and the granular material 1 2 stacked in the porous region 5. Therefore, 5 mm is preferable, and 5 to 30 mm is particularly preferable. If it is less than 5 mm, it is not preferable because accumulation of powder particles also occurs in the non-porous region 6 and the basis weight difference of the powder particles disappears. On the other hand, if it exceeds 30 mm, the area where the basis weight of the granular material is low becomes large and the rigidity of the absorbent body decreases, which is not preferable.

The non-porous region 6 is disposed in the peripheral region of the absorber forming region 15. This is because the central part of the absorbent body comes into contact with the excretory part when the absorbent article is used. Therefore, it is necessary to increase the basis weight of the granular material and increase the absorbency of the absorber, but in the peripheral region, the higher absorbency is not required than in the central region. Preferably, the non-porous region 6 is preferably disposed at a position of 5 mm to 15 mm from the outer edge of the absorber forming region 15. This is because if the distance from the outer edge is less than 5 mm, the pile shape may collapse. In addition, the distance between two adjacent non-porous regions is preferably in the range of 5 mm to 20 mm from the viewpoint of reducing discomfort when the absorbent article is mounted and reducing deformation due to the rigidity of the absorbent body.

 The arrangement pattern of the non-porous region 6 is not particularly limited as long as it is in the peripheral region of the absorber forming region 15, but for example, it is arranged in a staggered manner in the short side direction of the absorber forming region 15 as shown in FIG. Alternatively, they may be arranged in a line in the longitudinal direction of the absorbent body forming region 15 as shown in FIG. Alternatively, they may be arranged in a line in the short direction of the absorber formation region 15 ((b) in FIG. 4) or in the entire peripheral region of the absorber formation region 15 ((c) in FIG. 4). The area of the non-porous region 6 is 10% or more of the entire area of the absorber forming region 15. If it is less than 10%, the effect of reducing the fine particle volume is reduced, which is not preferable.

As shown in FIG. 5, in the perforated region 5 of the stacking support 3, since the holes are formed on the opposite side from the surface of the stacking support 3, the powder particles are thickly laminated by the suction means. A “high basis weight area” can be formed. On the other hand, in the non-porous region 6, since no pores are formed, it is difficult to stack the powder particles. Therefore, the non-porous region 6 can form a “low basis weight region” compared to the porous region 5. In the peripheral region of the excretion part where prevention of deformation of the absorbent body is prioritized over the improvement of excretion absorbability, when the basis weight is uniformly reduced, the rigidity is uniformly reduced. The absorbent body formed by the fiber stacking device has a structure in which the low basis weight region is surrounded by the high basis weight region in the peripheral region, and therefore, the absorption due to the rigidity of the high basis weight region. Deformation of the collector can be prevented.

The basis weight of the high basis weight region is preferably 2500 g / m ² or less, more preferably from about 140 to about 180 g / m ² , and particularly preferably about 160 g / m ² . ² . When the basis weight exceeds 2500 g / m ² , fiber piles occur from the periphery of the non-porous region 6 to the center of the non-porous region 6, and the difference in basis weight between the perforated region 5 and the non-porous region 6 Is not preferable. The basis weight of the low basis weight region is preferably about 50 to about 90 g / m ² , particularly preferably about 75 g / m ² . The basis weight of the high basis weight region is preferably at least 1.5 times the basis weight of the low basis weight region.

 In another embodiment of the fiber stack support 3 according to the present invention, in addition to the porous region 5 and the nonporous region 6, a low porosity region is further provided so as to surround the nonporous region 6. It may be done. Here, the perforated region having a porosity of 6 to 60% includes a high porosity region having a relatively high aperture rate within the range of the aperture rate, and a high aperture rate region. There is a low porosity area that has a lower porosity, and at least a part of the low porosity area is in contact with the high porosity area in order to prevent deformation of the absorber. It is necessary. The width of the low porosity area is usually 2 to 30 mm, and preferably 5 to 20 mm.

 FIG. 6 shows a plan view of one embodiment of the absorbent body of the present invention having a low porosity area, and FIG. 7 shows a cross-sectional view taken along the line AA ′. In the present embodiment, the absorber forming region 15 is further provided with a low porosity region 11 surrounding the non-porous region 6.

In the present embodiment, the basis weight of the granular material stacked on the stacking support 3 increases in the order of the non-porous region 6, the low porosity region 11, and the high porosity region 10. Therefore, a gentle basis weight distribution is generated in the direction from the high porosity area 11 to the non-porous area 6. For this reason, the level difference between the non-porous region 6 and the high-aperture area 10 can be reduced, and the uncomfortable feeling when the absorbent article is attached can be reduced. In both cases, deformation due to the rigidity of the absorber can also be reduced.

 Two or more types of low porosity areas may exist, and they may be provided in the same circle. By providing two or more types of low-aperture areas around the non-porous area 6, further reducing the level difference between the non-porous area 6 and the high-aperture area 10, and mounting absorbent articles This reduces the sense of incongruity, and the deformation due to the rigidity of the absorber. In that case, these low porosity areas are different from each other, and the low porosity area having the lowest porosity around the non-porous area 6 is further divided into the low porosity areas. It is preferable that a low porosity region having a higher porosity is disposed around the periphery of the substrate.

 The granular material used in the present invention is usually a mixture of pulverized pulp obtained by pulverizing sheet-like wood pulp and a superabsorbent polymer. For example, artificial pulp fibers such as chemical pulp, cellulose fiber, rayon, and acetate can be used instead of wood pulp. Examples of the superabsorbent polymer include starch-based, acrylic acid-based, and amino acid-based particulate or fibrous polymers. A heat sealing material for thermally fusing the powder particles may be further added to the powder particles. Examples of the heat sealing agent include particulate or fibrous thermoplastic resins such as polyethylene, polyethylene copolymer, polypropylene, polypropylene copolymer, polyethylene terephthalate, and polyethylene terephthalate copolymer. .

The method for producing a stacking fiber support 3 according to the present invention has a non-porous region 6 and a perforated region 5, and the perforated region and the non-porous region have a predetermined size and are arranged at predetermined positions. The method is not particularly limited as long as it is a method capable of forming the formed support, but is preferably manufactured by subjecting a metal or resin plate to chemical processing such as etching or physical processing such as punching. Yes (Japanese Patent Laid-Open No. 2 0 0 5 — 2 8 8 9 60). concrete It is preferable that the metal plate is covered with a chemical-resistant protective resin coating, and the metal plate in a portion not covered with the coating with a corrosive agent is corroded to form a hole, which is preferably manufactured by etching. .

 Since the conventional general fiber stack support is formed of a fibrous knitting made of metal or the like, in order to form a non-porous region, a plurality of supports or a non-blocked non-woven support is formed. It was necessary to place breathable parts on the pile support. Therefore, depending on how the supports were stacked and the arrangement of the blocks, the air flow was disturbed on the support, and the lamination was not stable at the shadowed area of the blocks. On the other hand, the fiber stack support 3 according to the present invention has the porous region 5 and the non-porous region 6 formed on one support by etching, so that There is no step between the body and the fiber-laying process and transfer to the conveyor 4 is stable. An example of production of the fiber stack support 3 (FIG. 3) is shown below. Etching is applied to a 0.3 mm thick stainless steel plate (SUS 3 0 4) by a conventional method to form a circular hole with a diameter of 0.3 mm, and the hole is 60 mm with a pitch of 0.5 mm. It is formed in a staggered pattern, with a minimum rib width of 0.2 mm, an open area ratio of 3 2.6%, and a ratio of the maximum hole diameter to the pile support thickness of 1.0. It was. The ratio of the area of the non-porous region to the entire area of the absorber formation region was 24.6%.

 In this etched fiber stack support 3, in order to increase the basis weight of the granular material in the central region of the absorber, in particular in the perforated region that will be the central region of the absorber formation region. Further, a recess for forming the absorber may be further formed.

Claims

The scope of the claims 1. A granular material having a rotating drum provided with means for sucking on the inner surface side and a plurality of fiber stacking supports disposed on the outer peripheral surface of the rotating drum, and supplied into the chamber by the sucking means An absorbent body forming apparatus for forming an absorbent body by stacking the absorbent body on the absorbent body forming region of the stacking fiber support, wherein the absorbent body forming region has a perforated region and a nonporous region And the said non-porous area | region is arrange | positioned so that it may be enclosed by the said perforated area | region in the peripheral area | region of this absorber formation area.  2. The fiber stacking apparatus according to claim 1, wherein the non-porous region is disposed at a position of 5 mm to 15 mm from an outer edge of the absorber forming region.  3. The fiber stacking apparatus according to claim 1 or 2, wherein an interval between two non-porous regions adjacent to each other is 5 mm to 20 mm.  4. The fiber stacking apparatus according to any one of claims 1 to 3, wherein the fiber stack supporting body further includes an absorbent body forming concave portion with respect to an outer peripheral surface of the rotating drum.  5. The fiber stacking apparatus according to any one of claims 1 to 4, wherein the perforated region is formed by etching.  6. The low porosity area having a lower porosity than the perforated area is further disposed so as to surround the non-porous area and so that at least a part thereof is in contact with the perforated area. The fiber stacking device according to any one of claims 1 to 5.  7. The fiber stacking apparatus according to any one of claims 1 to 6, wherein a thickness of the fiber stack support is uniform. 8. Absorbent body having areas where the basis weights of the powder particles are different from each other, and a high basis weight area having a high basis weight is disposed in the central area of the absorbent body, and the basis weight is lower than the high basis weight area. Basis weight area is in the peripheral area of the absorber The absorber, which is disposed so as to be surrounded by a region. 9. The absorbent body according to claim 8, wherein the basis weight of the high basis weight region is 2500 g / m ² or less and 1.5 times or more the basis weight of the low basis weight region.  10. The absorbent body according to claim 8 or 9, wherein the low basis weight region is disposed at a position of 5 mm to 15 mm from an outer edge of the absorbent body.  11. The absorbent body according to claim 8, wherein an interval between two adjacent low basis weight regions is 5 mm to 20 mm.  1 2. An area having a basis weight between the basis weight of the high basis weight area and the basis weight of the low basis weight area surrounds the low basis weight area, and at least a part thereof The absorbent body according to any one of claims 8 to 11, further arranged so as to be in contact with a basis weight region.