JP4115077B2 - Absorber and production method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an absorbent body and a method for producing the same, which are less prone to migration and swelling inhibition of the absorbent material, have excellent absorption performance, and can be produced efficiently and economically.
[0002]
[Prior art and problems to be solved by the invention]
As a technique for preventing the movement of an absorbent material such as a superabsorbent polymer in the absorbent body, a technique for forming a concave pocket for filling the absorbent material and filling the pocket with the absorbent material (Japanese Patent Laid-Open No. 10-1990). 14978 and the like) and a web containing an absorbent material by joining the outer sheets arranged on the front and back surfaces with heat or hot melt to divide the web into a plurality of parts (Japanese Patent Laid-Open No. 10-137291) )It has been known.
However, in the former technique, it is necessary to individually fill each pocket with an absorbent material, and it is necessary to align the position of filling the absorbent material into each pocket, which takes time and cost for manufacturing.
Further, in the latter technique, there is a risk that holes or scratches may occur in the outer sheets due to the bonding between the outer sheets, and when bonding with heat, it is necessary to include a heat-fusible material. . Furthermore, the swelling of the water-absorbing material is hindered, and the required absorption performance may not be obtained.
[0003]
Accordingly, an object of the present invention is to provide an absorbent body and a method for producing the same, which are less likely to inhibit the movement and swelling of the absorbent material, have excellent absorption performance, and can be produced efficiently and economically. It is in.
[0004]
[Means for Solving the Problems]
The present invention provides a perforated sheet obtained by extending a sheet material having a large number of slits so as to widen the slit, an absorbent material filled in a hole portion of the perforated sheet, and the perforated sheet. The object is achieved by providing an absorbent body comprising a covering sheet for covering the front and back surfaces.
[0005]
The present invention is a method of manufacturing an absorbent body having a perforated sheet and an absorbent material filled in the hole portion of the perforated sheet, wherein a sheet material having a large number of slits is widened. A step of obtaining a perforated sheet by stretching, and supplying the absorbent material onto the obtained perforated sheet and sucking the absorbent material from the back side of the perforated sheet to obtain the absorbent material The object is achieved by providing a method for producing an absorbent body comprising a step of filling a hole portion of a perforated sheet.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described based on a preferred embodiment thereof.
As shown in FIGS. 1 to 3, the absorbent body 1 as an embodiment of the absorbent body of the present invention is a perforated material obtained by extending a stretchable sheet material having a large number of slits so as to expand the slits. The sheet 2 includes an absorbent material 3 filled in the hole 21 of the perforated sheet 2, and covering sheets 4 and 5 that cover the front and back surfaces of the perforated sheet 2.
[0007]
The stretchable sheet material has a large number of slits, can be expanded in at least one direction to expand the slits, and when the extended external force is released, the expanded direction is It is a sheet material that can be elastically shrunk in the opposite direction.
The perforated sheet 2 is obtained by extending a stretchable sheet material and expanding slits in the sheet material, and has a predetermined thickness.
The hole portion 21 of the perforated sheet 2 is a through-hole penetrating between the front and back surfaces of the perforated sheet 2 and has a shape and a size capable of filling a predetermined amount of the absorbent material 3 therein.
[0008]
The thickness T of the perforated sheet 2 can be adjusted as appropriate according to the type of absorbent article in which the absorbent body 1 is used, but is 30 mm or less, particularly 1 to 10 mm. It is preferable from the viewpoint of the filling amount.
Moreover, although the opening area of the one hole part 21 can be suitably adjusted according to the kind etc. of the absorbent article in which the absorber 1 is used, it is 0.05-25 cm < ² >, It is especially 1-16 cm < ² >. From the viewpoint of the movement of the absorbent material and the prevention of swelling inhibition.
[0009]
In the hole portion 21, the ratio (L1 / L2) of the length L1 of the perforated sheet 2 in the extension direction Y to the length L2 in the direction orthogonal to the extension direction Y of the perforated sheet 2 is 0.1 to 10. In particular, 0.5 to 3 is preferable.
Moreover, the total opening area S1 of the hole 21 in the perforated sheet 2 has a ratio (S1 / S2) to the area (planar area) S2 of the absorbent body 1 of 0.1 or more, particularly 0.5 to 0.8. It is preferable from the viewpoint of absorption performance and prevention of movement of the absorbent material.
[0010]
As a material for forming the perforated sheet 2, urethane foam, non-woven fabric, cloth, paper, film, etc., and composite sheets thereof can be used.
The perforated sheet 2 preferably has elasticity in the thickness direction.
Examples of the perforated sheet 2 having elasticity in the thickness direction include a sheet made of urethane foam, a sheet made of a fiber aggregate containing elastomer fibers, and a sheet made of a fiber aggregate processed into a concavo-convex shape.
When the perforated sheet 2 having elasticity in the thickness direction is used, the cushioning property of the absorbent article using the absorbent body 1 is improved, and an absorbent article excellent in wearing feeling can be obtained. As a result, it is possible to effectively prevent deterioration of the surface feel of the absorbent article due to polymer particles (such as a crispness) that occurs when a large amount of granular superabsorbent polymer is used as No. 3.
[0011]
The covering sheets 4 and 5 are sheets that prevent leakage of the absorbent material from the absorbent body 1. As in this embodiment, when the front and back surfaces of the perforated sheet 2 are covered with different sheets, at least one of the covering sheets is liquid permeable.
In the absorbent body 1 of the present embodiment, the covering sheet 4 is air permeable and the covering sheet 5 is liquid permeable.
[0012]
The absorbent body 1 according to the present embodiment will be described in more detail. The absorbent body 1 has a vertically long rectangular shape in the extending direction Y of the perforated sheet 2 (the direction in which the stretchable sheet material is extended). The holes 21 are regularly arranged so as to form a plurality of rows in the longitudinal direction and the width direction of the perforated sheet 2 (absorbent body 1), and in any direction of the longitudinal direction and the width direction In addition, the hole portions forming one adjacent row and the hole portions forming the other row are arranged at alternate positions. The perforated sheet 2 has a net shape as a whole. The shape of the opening of each hole 21 has a substantially hexagonal shape that is slightly crushed in the longitudinal direction as shown in FIG.
Further, the covering sheets 4 and 5 are bonded to the front and back surfaces of the perforated sheet 2 by adhesives (not shown) applied in a loop shape, a spray shape, etc., respectively, 41 and 41 are wound up on the other covering sheet 5, and are fixed on the covering sheet 5 with an adhesive (not shown).
[0013]
Each hole 21 is filled with a fiber component 31 such as pulp fiber and a superabsorbent polymer 32 as the absorbent material 3. As the fiber component 31 and the superabsorbent polymer 32, those conventionally used for absorbent articles of absorbent articles such as sanitary napkins and disposable diapers can be used without particular limitation.
[0014]
The absorbent body 1 of this embodiment is interposed between a liquid-permeable top sheet and a liquid-impermeable back sheet, for example, and is used in combination with disposable diapers, sanitary napkins, incontinence pads, and diapers. It is preferably used as an absorbent body of various absorbent articles such as absorbent articles for absorbing body fluids (including urine).
Moreover, the absorber 1 of this embodiment can be used alone as an absorbent article. For example, one of the covering sheets 4 and 5 is a liquid-permeable sheet, the other is a liquid-impermeable sheet, and the absorber itself is an absorbent article such as a sanitary napkin, an incontinence pad, or an absorbent pad. It can also be used.
[0015]
According to the absorbent body 1 of the present embodiment, the absorbent material 3 is filled in the hole 21 formed by expanding the slit of the sheet material having the slit, and therefore the movement of the absorbent material 3 Is prevented, and a decrease in absorption performance, leakage of the absorbent material, and the like due to bias of the absorbent material, gel blocking, and the like are prevented.
Further, since the absorbent material 3 is filled in the hole 21 formed by expanding the slit of the sheet material having a slit, when the absorbent material 3 absorbs liquid and swells, The inner wall of the hole portion 21 and the shape of the hole portion 21 are flexibly deformed, and the swelling of the absorbent material 3 is hardly inhibited. Thereby, since the absorptive material 3 contributes to the improvement of absorption performance without waste, it is excellent in absorption performance.
Further, since the hole 21 is formed by expanding the slit of the sheet material having the slit, the process of forming the hole 21 is simplified and can be manufactured efficiently and economically.
[0016]
FIG. 4 is a diagram illustrating an example in which the absorbent body 1 having the above configuration is used as an absorbent body of a disposable diaper. A disposable diaper 6 shown in FIG. 4 is formed by interposing the above-described absorber 1 between a liquid-permeable top sheet 61 and a liquid-impermeable back sheet 62.
This disposable diaper 6 has a substantially vertically long shape, and is provided with a pair of fastening tapes 63, 63 on the left and right side edges of the back side portion disposed on the wearer's back side. A three-dimensional gather 64 is formed on both sides in the longitudinal direction.
The absorbent body 1 is sandwiched and fixed between the sheets 61 and 62 so that the extending direction of the perforated sheet 2 (longitudinal direction of the absorbent body 1) coincides with the longitudinal direction of the diaper 6.
[0017]
Since the disposable diaper 6 has the absorbent body 1 configured as described above interposed between the front and back sheets 61 and 62, it is possible to prevent a decrease in absorption performance, leakage of an absorbent material, and the like and to have excellent absorption performance. is there.
In addition, the absorber 1 can be arrange | positioned so that the expansion | extension direction of the perforated sheet 2 may correspond with either the longitudinal direction or width direction of absorbent articles, such as a disposable diaper.
In the disposable diaper 6, as the forming material of the top sheet 61, the back sheet 62, the fastening tape 63, and the three-dimensional gather 64, various materials conventionally used for disposable diapers can be used without particular limitation.
[0018]
Next, a preferred embodiment of the method for manufacturing an absorbent body according to the present invention will be described with reference to FIG.
FIG. 5 shows a manufacturing apparatus preferably used in the manufacturing method of the present embodiment. In the manufacturing apparatus 7, the slit 11 expands the slit forming portion 71 into which the slit 11 is placed and the stretchable sheet material 10 into which the slit 11 is put into the stretchable sheet material 10 that is continuously conveyed. In addition, the pulp fiber 31 and the superabsorbent polymer 32 as the absorbent material 3 are supplied to the stretched portion 72 that is elongated in this manner and the perforated sheet 2 in which a large number of hole portions 21 are formed by stretching, and the perforated sheet. 2 is provided with an absorptive material supply filling unit 73 that sucks the supplied absorptive materials 31 and 32 into the hole portions 21 and 21 of the perforated sheet 2.
[0019]
The slit forming portion 71 includes a cutting roll 71a provided with a large number of cutting blades formed in parallel with the axial length direction on a peripheral surface, and a receiving roll 71b disposed to face the cutting roll 71a. , 71b, slits 11 are inserted into the stretchable sheet material 10 in a predetermined pattern.
The stretching portion 72 utilizes the difference in peripheral speed between the rolls 71a and 71b and the pair of nip rolls 72a and 72b whose peripheral speed is faster than both the rolls 71a and 71b, and the stretchable sheet material 10 with slits. Is uniaxially stretched in the conveying direction.
The absorbent material supply filling unit 73 pulverizes and defibrates the supplied pulp sheet 30 and supplies the pulp fiber 31 as a pulverization / disintegration mechanism 73a, and the superabsorbent polymer 32 is joined to the pulp fiber 31 and supplied. A polymer supply mechanism 73b and an absorbent material suction mechanism 73c made of a vacuum conveyor are provided.
[0020]
In the manufacturing method of the present embodiment, first, slits 11 having a predetermined pattern are inserted into the stretchable sheet material 10 supplied to the slit forming portion 71 by both rolls 71a and 71b.
Next, the stretchable sheet material 10 in which the slits 11 are inserted is extended in the conveying direction in the extending portion 72. Thereby, each slit 11 expands and many hole parts 21 and 21 which penetrate between front and back surfaces are formed in an elastic sheet material.
Next, the perforated sheet 2 in which a large number of holes 21 and 21 are formed is conveyed to the absorbent material supply and filling unit 73, and the pulp fibers 31 and the superabsorbent polymer 32 are formed on the upper surface (surface). While being supplied, the pulp fiber 31 and the superabsorbent polymer 32 are sucked into the holes 21 and 21 of the perforated sheet 2 and filled by suction by the absorbent material suction mechanism 73c from the lower surface (back surface) side. Is done.
[0021]
In the manufacturing method of this embodiment, the 1st coating sheet 4 which has air permeability is supplied to the back surface side of the perforated sheet 2 before supplying the pulp fiber 31 and the superabsorbent polymer 32 as an absorbent material. Then, after the back surface of the perforated sheet 2 is coated, the pulp fiber 31 and the superabsorbent polymer 32 are supplied onto the perforated sheet 2 on the coated sheet 4, and then the pulp fiber 31 and the superabsorbent polymer are supplied. The second covering sheet 5 is supplied to the surface side of the perforated sheet 2 after supplying 32 to cover the surface of the perforated sheet 2. Thus, the perforated sheet 2 in which the hole 21 is filled with the absorbent material and the front and back surfaces are covered with the first and second covering sheets 4 and 5 is formed by the known cutting means 74. Then, it is cut into a length L corresponding to one absorbent article.
[0022]
According to the manufacturing method of the absorber of this embodiment, the absorber 1 can be manufactured efficiently and economically in this way. In particular, when filling each hole 21 with the absorbent material 3, it is not necessary to individually fill each hole 21 with the absorbent material, so alignment is not necessary, and in a simple manufacturing process, The absorber 1 in which the movement of the absorbent material 3 is prevented can be manufactured. Moreover, since it is not necessary to join the 1st and 2nd coating sheets 4 and 5 which coat | cover the front and back of the absorber 1 by heat seal etc., both coating sheets 4 and 5 contain a heat-fusible fiber. It may not be. In addition, since neither the perforations nor the scratches are generated in the covering sheets 4 and 5, for example, the obtained absorbent body 1 can be used as an absorbent article as it is. The absorbent material 3 is unlikely to leak out when used as an absorbent article as it is or when it is interposed between the top sheet and the back sheet to form an absorbent article.
[0023]
The absorbent body of the present invention can also be used as an absorbent body for pants-type diapers, sanitary napkins, incontinence pads, auxiliary pads used in combination with diapers, and the like.
Moreover, the front and back surfaces of the perforated sheet 2 in the absorbent body may be covered with a single liquid-permeable covering sheet. Moreover, the absorber which concerns on this invention can also be set as the structure which coat | covered the front and back of a perforated sheet | seat directly with a liquid-permeable coating sheet and a liquid-impermeable coating sheet. For example, in the manufacturing method of an absorber, it replaces with the 1st and 2nd coating sheets 4 and 5, and supplies the surface sheet 61 and the back surface sheet 62, and the front and back of the absorber 1 does not interpose another sheet material. Alternatively, an absorbent body having a configuration in which these front and back sheets 61 and 62 are directly covered may be manufactured.
Moreover, in the manufacturing method of an absorber, it can replace with forming the slit 11 in the elastic sheet material 10 in-line, and can also use the elastic sheet material which formed the slit in another line beforehand.
[0024]
In the present invention, the individual shapes of the slits 11 applied to the sheet material 10 may be linear, R-shaped, corrugated, or the like, and various combinations of slit dimensions, shapes, and arrangements may be used. Moreover, you may form the area | region which does not give the slit 11 intermittently with respect to the expansion | extension direction of the sheet | seat material 10. FIG. Further, the sheet material may be intermittently operated to form the opening and the non-opening.
In addition, even if the filling of the absorbent material is continuous, or when forming an efficient and economical absorbent body, a spraying device for the granular material as disclosed in JP-A-4-341368 and JP-A-8-215629 May be used to fill the absorbent material 3 intermittently.
In the present invention, the absorbent material 3 filled in the hole 21 may be only one of the fiber component 31 and the superabsorbent polymer 32. Further, the absorbent material 3 in the present invention may be deposited not only in the hole portion 21 but also in the non-opening portion of the perforated sheet 2.
[0025]
【The invention's effect】
The absorbent body and absorbent article of the present invention are less susceptible to migration of the absorbent material and inhibition of swelling of the absorbent material, have excellent absorption performance, and can be produced efficiently and economically.
According to the method for producing an absorbent body of the present invention, it is possible to efficiently and economically produce an absorbent body that is less likely to cause the movement of the absorbent material and inhibit the swelling of the absorbent material and has excellent absorption performance.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of an absorbent body according to the present invention.
FIG. 2 is a cross-sectional view taken along the line XX in FIG.
FIG. 3 is an enlarged plan view showing a part of the absorbent body of FIG. 1;
4 is a plan view showing an example of an absorbent article using the absorbent body of FIG. 1. FIG.
FIG. 5 (a) is a schematic view showing a production apparatus used in the method for producing an absorbent body of the present invention, and FIG. 5 (b) shows an absorbent body using the production apparatus of FIG. 5 (a). It is a figure which shows typically the state of the elastic sheet material, perforated sheet, and absorber in each process (stage) at the time of manufacture.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Absorber 2 Perforated sheet 3 Absorbent material 31 Pulp fiber (fiber component)
32 Superabsorbent polymer 4, 5 Cover sheet 6 Disposable diaper (absorbent article)
61 Front sheet 62 Back sheet

Claims (2)

A perforated sheet obtained by extending a sheet material having a large number of slits so as to widen the slit, an absorbent material filled in the holes of the perforated sheet, and covering the front and back surfaces of the perforated sheet It consists of a coated sheet,
The perforated sheet has elasticity in the thickness direction, and has a planar front and back surface and the hole portion penetrating between the front and back surfaces . It is a manufacturing method of the absorber according to claim 1,
A sheet material having a large number of slits is stretched so as to widen the slits to obtain a perforated sheet, and an absorbent material is supplied onto the obtained perforated sheet and the absorbent material is contained in the perforated sheet. A method of manufacturing an absorbent body comprising: sucking from the back surface side of the hole sheet and filling the hole in the hole sheet with the absorbent material.

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