JP3175934B2 - Disposable absorbent article and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disposable absorbent article and a method for producing the same, and more particularly to a disposable absorbent article such as a disposable diaper used for infants, adults and the like or for incontinent persons and a method for producing the same.

[0002]

2. Description of the Related Art In a conventional disposable diaper, for example, as disclosed in Japanese Patent Publication No. 52-40267, a liquid-permeable top sheet, a liquid-impermeable back sheet, and a And a pair of left and right side flaps are integrally formed on the diaper body, and are disposed on both side edges on the back side of the side flaps, and a fastening device is provided on the ventral side. There is known a so-called flat type which is fixed at the end.

Recently, Japanese Patent Application Laid-Open No. 57-77304 has been proposed.
As disclosed in Japanese Unexamined Patent Publication, a so-called pants-type disposable diaper in which a pair of left and right leg openings and a waist opening are formed by joining and fixing the abdominal region and the dorsal region of the pair of left and right side flaps to each other. Has been proposed. The pants-type disposable diaper is configured such that a leg opening and a waist opening are formed to be extendable and contractable, respectively, to fit a body shape. Such pants-type disposable diapers can usually be worn by the wearer in a standing position, and the "diaper separation" of infants
It is useful as a toilet training for promoting exercise, or for an incontinent person or a walkable adult.

Also, Japanese Utility Model Laid-Open No. 58-143809,
Japanese Patent Application Laid-Open No. 61-207605 discloses a flat-type and pants-type disposable diaper in which a backsheet is covered with a nonwoven fiber for the purpose of producing a disposable garment having a well-designed sewing appearance. It has been disclosed.

[0005] On the other hand, some proposals have also been made on a method of manufacturing disposable diapers. They are basically
JP-A-57-77304 and JP-A-1-29210
The cross-flow method in which the longitudinal direction of the absorber is perpendicular to the flow direction as shown in Japanese Patent Publication No. 2 (1993) -207, is represented.

[0006] Generally, these types of disposable diapers have the problem that the productivity is significantly reduced and the cost must be increased. That is, a technique for inserting an elongated elastic member in a direction perpendicular to the flow direction of the continuous web has not been established yet, and a decrease in productivity is caused by this.

Among them, a pants-type disposable diaper with a belt which does not require a side seal and a method of manufacturing the same are disclosed in JP-T-61-502264. I had to set it high.

[0008]

However, Japanese Utility Model Application Laid-Open No. 58-143809 and Japanese Patent Application Laid-Open No. 61-20
The disposable diaper described in No. 7605 is because the back sheet constitutes a diaper main body including a flap portion, even if the back sheet is a soft nonwoven fabric, it is inferior in water resistance, and therefore, over the entire back sheet. There is a problem in that a multi-layer laminated structure sheet or a laminated sheet has to be provided, resulting in high cost, deterioration of flap texture, and reduction in air permeability. Here, the above-mentioned texture is generally evaluated organoleptically, and refers to softness, appearance, gloss, feel, and the like.

Accordingly, it is an object of the present invention to provide a disposable absorbent article which is inexpensive, has an excellent flap feel, and has excellent air permeability, and a method for producing the same.

[0010]

According to the present invention, there is provided an absorbent body having a liquid-permeable topsheet, a liquid-impermeable backsheet, and an absorber disposed between the two sheets.
An outermost layer sheet that surrounds the waist when worn and holds the absorbent body against the wearer, wherein the outermost layer sheet has waist flaps provided at both ends in the longitudinal direction of the outermost layer sheet, respectively. to, respectively are disposed a plurality of elastic members, longitudinal concave portions formed on both sides of the central portion in the longitudinal direction of the outermost layer sheet
If less of the left and right pair of side flaps which extend outward in the width direction respectively between the end portion and the waist flap
The above object has also been achieved by providing a disposable absorbent article in which a plurality of different elastic members are arranged in the width direction at the center in the longitudinal direction .

Further, the present invention provides a method of manufacturing the above-mentioned absorbent article, which comprises a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorber disposed between these two sheets. The fixing step of intermittently arranging and fixing the main body to the belt-shaped outermost layer sheet band supplied continuously, and the cutting step of cutting the outermost layer sheet between the fixed absorbent bodies. The present invention also provides a method for producing a disposable absorbent article characterized by comprising:

According to the disposable absorbent article of the [0012] The present invention, the outermost layer sheet that囲撓the waist of the wearer, outermost
Provided at both ends in the longitudinal direction of the layer sheet.
Waist flap and the outermost layer sheet in the longitudinal direction.
Extending outward in the width direction on both sides of the central part
Each of the left and right side flaps has a plurality of elastic
Since the material is arranged , the absorbent material fits perfectly to the wearer
Goods can be fitted . In addition, since the absorbent main body is provided with the liquid-impermeable back sheet, the excrement absorbed by the absorbent main body does not leak.

Further, according to the manufacturing method for absorbent articles according to the present invention, by the child intermittently arranged in the continuous outermost layer sheet strip to an absorbent article main body described above, high-speed and continuous absorbent article of the present invention It can be easily produced .

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In the following examples, disposable diapers for infants will be described as examples of absorbent articles. Disposable diaper 1 according to an embodiment of the present invention
Is a so-called pants-type disposable diaper, which is composed of an outermost layer sheet 2 and an absorbent main body 3 fixed substantially at the center of the outermost layer sheet 2 as shown in FIG. I have.

The outermost layer sheet 2 is formed in a substantially rectangular shape having a size substantially larger than that of the absorbent main body 3, and the absorbent main body 3 is attached to a substantially central portion in the longitudinal direction. Also,
Concave notches 4 are formed on both sides to which the absorbent main body 3 is adhered, so that a leg opening is formed when a pants type is formed. A pair of left and right side flaps 5, 5, 6, and 6 extend outward from the both sides of the absorbent main body 3 in the width direction from above and below the constricted portion where the concave notch 4 is formed. ing.

A joining portion 7 is provided at each edge of the side flaps 5, 5, 6 and 6, and the upper and lower side flaps 5 and 6 are fused to each other at the joining portion 7 to form a pants type. Is formed.

A pair of waist flaps 8 and 9 extending outward from the absorbent main body 3 are provided at the longitudinal edges of the outermost layer sheet 2 so that the waist flaps are formed when the pants type is formed. The flaps 8 and 9 form a waist opening.

The waist flaps 8 and 9 are folded lines 10
The end of the absorbent main body 3 is sandwiched by this return, and the absorbent main body 3 is securely held. Further, the second elastic members 12 are respectively provided on the waist flaps 8 and 9 in the longitudinal direction of the side flaps 5 , 5 , 6 and 6 , respectively.
A third elastic member 13 is provided at the center to enhance the fit to the wearer when worn and prevent slippage.

When the absorbent main body 3 is attached to the outermost layer sheet 2, a constriction 14 is formed at substantially the center in the longitudinal direction corresponding to the concave notch 4 of the outermost layer sheet 2.

The absorbent main body 3 includes a liquid-permeable top sheet 15 forming a side in contact with the wearer's skin, a liquid-impermeable back sheet 16 corresponding to the top sheet 15, a top sheet 15 and a back sheet. 16 and an absorber 17 interposed therebetween. Also, the absorbent body 3 has a pair of left and right body flaps 18 extending outwardly in the width direction from both side edges of the absorber 17 and a pair of left and right body flaps 18. And a first elastic member 19 to be formed. The first elastic members 19 and 19 are arranged along the longitudinal direction of the absorbent main body 3 and are substantially perpendicular to the second elastic members 12 arranged on the waist flaps 8 and 9.

The top sheet 15 is used for absorbing excrement
It is preferable that the liquid-permeable sheet having a feel close to underwear is used as such a liquid-permeable sheet.
For example, a woven fabric, a nonwoven fabric, a porous film and the like are preferable.
In addition, a method of applying a hydrophobic compound such as a silicone-based oil agent or paraffin wax to a peripheral portion of the top sheet 15,
A hydrophilic compound such as an alkyl phosphate ester is applied in advance, and a water-repellent treatment is performed by a method of washing the periphery with warm water, so that leakage due to bleeding of urine or the like at the periphery can be prevented.

The back sheet 16 is made of a thermoplastic resin to which a filler is added and stretched, and is a moisture-permeable liquid-impermeable sheet or a sheet having a feel similar to underwear, for example, a composite material of a film and a nonwoven fabric or a film and a woven material. A composite material of cloth or the like is used.

The absorbent 17 is preferably composed mainly of fibrillated pulp and used in combination with a high-molecular-weight water-absorbing polymer. In addition, a heat-treated mixture of a thermoplastic resin, cellulose fibers, and a high-molecular-weight water-absorbing polymer is preferable. The location of the high-molecular-weight water-absorbing polymer may be any of the upper layer, the middle layer, and the lower layer, and may be a mixture with pulp. The high-molecular water-absorbing polymer has a holding performance of absorbing and holding a liquid 20 times or more its own weight, and is preferably in the form of particles having a gelling property. For example, starch-acrylic acid (salt) graft copolymer, starch-acrylonitrile acid (salt)
Polymers and the like are preferred. The shape is preferably an hourglass that matches the body shape of the wearer, but may be rectangular.

The outermost layer sheet 2 is preferably a liquid-impermeable, air-permeable, highly flexible sheet having a feeling similar to underwear, and such a sheet is subjected to a water-repellent treatment. Woven fabrics, non-woven fabrics and the like can be mentioned. It is preferable to prevent leakage due to bleeding of urine or the like.

Although not shown, in a disposable diaper in which the wing-held absorbent main body 3 is integrally joined to the outermost layer sheet 2, if the gathered wing portion is formed without joining, A double flap is formed in the crotch region, and the wing portion of the absorbent main body 3 forms a gather having a three-dimensional shape, and exhibits a leakage preventing effect.

The first, second, and third elastic members 19, 12,
13 is joined to the absorbent main body 3 and the outermost layer sheet 2 in a generally stretched state using means known in the art such as ultrasonic welding, heat welding, and an adhesive. The material, thread rubber, a flat rubber, foamed polyurethane film-type rubber or tape-like, whatever Ru can be used as long as known in the art. Generally, the arrangement of the left and right side flaps, the pair of upper and lower waist flaps, and the elastic members at the left and right waist side portions is symmetric. Further, those having a stress at 150% elongation of 70 to 100 g are particularly preferable.

Further, as shown in FIG. 1, the first elastic member 19 may be arranged in a curved line along the concave portion.

Next, a disposable diaper 21 according to a second embodiment of the present invention will be described with reference to FIG. still,
In FIG. 2 and the following description, the second and third elastic portions
Although illustration and explanation of the material are omitted, the second and third bullets
The elastic member is the same elastic member as in the first embodiment described above.
Placed in The disposable diaper 21 of the second embodiment
Is a so-called flat disposable diaper. In the second embodiment, since other schematic configurations are the same as those of the above-described first embodiment, the same parts as those of the first embodiment are denoted by the same reference numerals, and Detailed description is omitted.

The outermost layer sheet 2 is formed in a substantially hourglass shape, and tape fasteners 23 are provided on the back flaps 22 and 22 and are adhered to the abdominal area and held on the wearer's waist. It is supposed to.

The absorbent main body 3 is extended in a rectangular shape,
The outermost layer sheet 2 extends from the back waist flap 8 to the abdominal waist flap 9.

At both end portions 26 in the longitudinal direction of the absorbent main body 3, the liquid-impermeable back sheet end flaps 16a
Are folded back, and leakage of the waste absorbed by the absorber 17 is prevented. Further, the both end edge portions of the absorbent main body 3 are folded back portions 8a, 9 of the waist flaps 8, 9, respectively.
Thus, the outermost sheet 2 is covered so as to be sandwiched by the outermost sheet 2a, so that the absorbent main body 3 is securely held and the excrement is prevented from leaking.

In the absorbent body 3, the body flap 18
An elastic member 19 is stretched over the leg, so that a gather is formed in the leg portion (the concave portion 4).

Next, a preferred embodiment for producing the absorbent article of the present invention will be described. First, a first embodiment of the present invention will be described with reference to FIG. In this first embodiment, the absorbent body 3 is
It is manufactured by a so-called vertical flow method in which the longitudinal directions are arranged in parallel.

The absorbent body 3 is not shown in FIG. 3, but absorbents 17 such as defibrated fibers are successively placed on a continuous belt-shaped back sheet 16 at regular intervals, and a continuous belt-like material is placed on this. And the space between the absorbers 17 is welded. On the other hand, the first elastic member 19 is stretched in the longitudinal direction on the back sheet 16 in advance.

In this way, the strip 30 having the continuous absorbent main body 3 is manufactured, and as shown by the arrow A in FIG.
A reversing device 3 in which the absorbent main body 3 is connected in the longitudinal direction.
Convey to 1.

In front of the reversing device 31, an adhesive coating device 32 is provided.
The adhesive is continuously applied to one surface of the belt-like body 30 so that the adhesive is applied to the entire surface on the 6 side.

After the band 30 of the absorbent main body 3 to which the adhesive is applied is supported by the head of the reversing device 31, it is cut along the imaginary line 34 by the cutting device 33, and the individual absorbent main body 3 is manufactured. Is done. Each of the absorbent bodies 3 is rotated by about 90 ° on the reversing device 31 until reaching the polymerization roll 34 while being supported by the head of the reversing device 31 (reversing step).

The reversing device 31 is provided with arms extending radially around the axis, and a support head at the end of each arm. The support head has an anvil corresponding to the cutting device 33, a suction system, a pin hold, and a mechanical chuck. For example, support means for the absorbent body 3 are provided. Also, the support head reaches the polymerization roll 34 via the cutting device 33,
A mechanism is provided for transporting the absorbent body 3 while reversing it by 90 °. The separated individual absorbent main bodies 3 are supported by the head, and the elastic members 1 disposed on the absorbent main body 3
9 while being kept flat without being affected by the shrinkage stress of 9;
It will be sent to the polymerization roll 34. During this reversing step, the end flaps 8a and 9a are
(See FIG. 1.) It is preferable to incorporate a step of folding back on the upper surface.

On the other hand, the third elastic member 13 in the extended state forms an elastic tape 37 intermittently or continuously joined to the support sheet 36, and the elastic tape 37 is transferred to the intermittent transfer device 3.
Send to 8. On the surface of the intermittent transfer device 38, the stretchable tape 37 supported in an extended state is cut into individual stretchable tapes 40 by a cutter 39 and sent intermittently to a polymerization roll 41. The elastic tape 40 forms a gather at the waist side portion.

On the other hand, the outermost sheet band 42 is unwound from the raw material, and the second elastic members 12 are arranged on the left and right side edges of the strip 42 of the outermost layer sheet.
4 is sent to the polymerization roll 41. The second elastic member 12 forms a gather that covers the waist opening.

In the polymerization roll 41, the elastic tape 40 formed in the above step is intermittently arranged on the outermost layer sheet band 42 and integrally joined. At this time, the third elastic member 13 is disposed between the support sheet 36 and the outermost sheet band 42. After that, in a winding step 42, the waist flaps 8 and 9 are formed by coating the waist elastic member 12 by winding the both side edges 43.

Next, in the reversing device 31, about 90 °
The inverted individual absorbent main bodies 3 are overlaid on the outermost layer sheet 2 by the polymerization roll 34 and are integrally joined to the outermost layer sheet 2 with an adhesive (fixing step). At this point, the second extendable and retractable member is in a position parallel and perpendicular to the flow direction.
Then, the disposition of the first elastic members 12 and 19 is completed, and the disposable diaper web 49 is obtained.

Thereafter, a leg hole 46 as the concave notch 4 is formed between the adjacent absorbent bodies 3 by a rotary die cutter 45. As a method of forming the leg holes 46, a method such as water jet or punching may be used in addition to the rotary die cutter method. Next, the disposable diaper web 49 is folded by two folding means 48.
Is folded in half using a center line parallel to the flow direction as a reference line.

The folded disposable diaper web 49 is
The outermost sheets are integrally sealed by ultrasonic welding or the like at a substantially intermediate position between the absorbent bodies 3 and 3 by the sealing device 51 (side seal). This sealing is performed intermittently.

The disposable diaper web 49 having finished the side seal is cut into individual disposable diapers 1 by the final cutter unit 52 (cutting step). The cutting is performed in the side seal portion, and the cut portion becomes the joint 7 (see FIG. 1). Ultrasonic sealing is performed to obtain an appropriate seal strength and seal width so that the seal portion does not peel off immediately after cutting. Thus,
The stretchable complete pants-type disposable diaper 1 is obtained. The state in which the joining portions 7, 7 of the disposable diaper 1 are peeled off and the stretchable portion is stretched and expanded is almost equivalent to the diaper shown in FIG.

Next, a second embodiment will be described with reference to FIG. This second embodiment is an embodiment of a method for manufacturing a disposable diaper 21 according to the second embodiment, that is, a flat type disposable diaper. Further, in the second embodiment, the absorbent main body 3 is of a vertical flow type in which the absorbent main body 3 flows in parallel to the longitudinal direction.

Although the band 30 of the absorbent main body 3 is not shown in FIG. 4, absorbents 17 such as defibrated fibers are sequentially placed on a continuous band-shaped back sheet 16 at equal intervals. It is manufactured by covering the top with a continuous band-shaped top sheet 15 and bonding. On the other hand, the first elastic member 19 is stretched in the longitudinal direction on the back sheet 16 in advance.

In this manner, the strip 30 having the continuous absorbent main body 3 is manufactured, and as shown by the arrow B in FIG.
A reversing device 3 in which the absorbent main body 3 is connected in the longitudinal direction.
Convey to 1.

In front of the reversing device 31, an adhesive coating device 32 is provided.
The adhesive is continuously applied to one surface of the belt-like body 30 so that the adhesive is applied to the entire surface on the 6 side.

[0050] In the above embodiment, the adhesive is fully applied to the backsheet 6, although the amount can be minimum pattern coating, As the coating process,
There are bead, coater, spray, transfer, screen, gravure, etc.

Then, the absorbent body 3 is cut by the cutting device 33 along the imaginary line 34, and the individual absorbent main bodies 3 are manufactured. The cut absorbent body 3 is rotated by about 90 ° by the reversing device 31.
After being rotated, it is intermittently fed to the polymerization roll 34.

On the other hand, the outermost layer sheet band 42 is unwound from a raw material (not shown) and sent to the polymerization roll 34 where the absorbent body 3 and the outermost layer sheet band 42
Are integrally joined via an adhesive applied to the article body to form a disposable diaper web 49.

An integrated disposable diaper web 49
Next, a leg hole 49 is formed by a rotary die cutter 45 and cut into individual disposable diapers 21 by a final cutter unit 52. Then, the tape fastener 23 is attached to the side flap 22 in the next step.

Next, a third embodiment will be described with reference to FIG. In the third embodiment, an example of a cross-flow method in which the absorbent main body 3 flows in the longitudinal direction perpendicular to the flow direction is shown.

In the third embodiment, the outermost sheet 2 on which the absorbent main body 3 is intermittently arranged is further provided with a top sheet 55 unwound from the raw material by a polymerization roll group 56. They are joined together. Other manufacturing steps are substantially the same as those of the second embodiment. According to the disposable diaper 58 obtained according to the third embodiment,
The topsheet 55 allows the absorbent body 3 to be more securely fixed.

Each of the absorbent bodies 3 separated in the cutting step 33 is supported by the head of the intermittent transfer device 57 and is affected by the contraction stress of the elastic member 19 disposed in advance on the absorbent body 3. It is fed to the polymerization roll 34 while maintaining a flat shape. It is preferable to include a step of folding the end flap 16a on the upper surface of the absorber in the intermittent transfer step.

In the disposable diapers 1, 21, and 51 obtained by the method according to the first, second, and third embodiments described above, the back sheet 16 is disposed only at the portion where the absorber 17 is placed. So the flap is highly flexible,
And rich in breathability.

The use of such a manufacturing method has an advantage that a nonwoven fabric having a sufficient strength can be supplied with respect to the tensile stress applied when the diaper is fixed to the wearer using the tape fastener. As a material used for such a disposable absorbent article, for example, a nonwoven fabric or the like is thin in view of cost. At that time, the nonwoven fabric wrapped in the raw fabric has a strength in the long direction that is 5 to 6 times better than the strength in the short direction. In this manufacturing method, it is possible to arrange the long direction in the direction in which the stress of the tape fastener is applied, and a very rational product design can be achieved.

As described above, according to the manufacturing method of the above embodiment, the elastic member can be easily arranged, and the absorbent article of the present invention can be manufactured without impairing high-speed productivity.

It is needless to say that the embodiments of the absorbent article according to the present invention and the method of the present invention can be arbitrarily modified without departing from the spirit of the present invention.
For example, a configuration in which a tearing guide means is disposed adjacent to a side seal portion of the disposable diaper 1 of a complete pants type so that the tearing guide means can be easily peeled off from a wearer. The tear guide means, or a notch guide line, or a seal portion, which can be torn easily pulled while has torn during wear, the strength that will not tear or .

According to another embodiment of the method of the present invention, the absorbent body 3 flows perpendicular to the longitudinal direction of the body,
At this time, the first elastic body for the waist is inserted. Each body 3 is rotated 90 ° to make the diaper web longitudinally flow.
At this time, the second elastic body for the leg is inserted.

[0062]

According to the disposable absorbent article according to the present invention, the disposable absorbent article is inexpensive, has an excellent flap feel, and can be fitted to a wearer exactly. A manufacturing method can be provided.

Another advantage of the method of the present invention is that when the reversing device is used to transfer the absorbent main body to the outermost layer sheet, if the elastic member is stretched in the flow direction of the main body of the article, the main body of the article becomes 90%. When it is turned over and transferred to the outermost layer sheet, an elastic member extending in the direction perpendicular to the flow direction is disposed. Therefore, by inverting the elastic member integrally with the article main body, the inversion arrangement is facilitated. That is, the arrangement of the elastic member in the direction perpendicular to the flow direction has conventionally often reduced the high-speed productivity of the absorbent article. However, it is technically difficult to handle a single thread-like or band-like elastic member. It was due to something.

[Brief description of the drawings]

FIG. 1 is a partially cutaway plan view of a disposable diaper according to a first embodiment of the present invention in an unfolded state.

FIG. 2 is a partially cutaway plan view showing a disposable diaper according to a second embodiment in a developed state.

FIG. 3 is a perspective view showing a method for manufacturing a disposable diaper according to the first embodiment of the present invention.

FIG. 4 is a perspective view showing a method for manufacturing a disposable diaper according to a second embodiment.

FIG. 5 is a perspective view showing a method for manufacturing a disposable diaper according to a third embodiment.

[Explanation of symbols]

 1, 21; Disposable diaper 2; Outermost layer sheet 3; Absorbent body 12, 13, 19; Elastic member 15; Top sheet 16; Back sheet 17; Absorber 31; Process) 52; cutting device (cutting process)

Claims (3)

(57) [Claims] 1. An absorbent body having a liquid-permeable topsheet, a liquid-impermeable backsheet, and an absorber disposed between the two sheets, and the absorbent body surrounding a waist when worn. And an outermost layer sheet for holding the outermost layer sheet against a wearer, wherein the outermost layer sheet has a plurality of elastic members disposed on waist flaps provided at both end edges in the longitudinal direction of the outermost layer sheet, respectively. A pair of left and right pair of right and left extending in the width direction respectively between the longitudinal end portion of the concave notch formed on both sides of the central portion in the longitudinal direction of the outermost layer sheet and the waist flap. A disposable absorbent article in which a plurality of different elastic members are disposed in the width direction at least in a central portion of the side flap in the longitudinal direction . 2. The method for producing a disposable absorbent article according to claim 1, wherein a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorber disposed between the two sheets. A fixing step of intermittently arranging and fixing the absorbent main body having the belt-shaped outermost layer sheet supplied continuously, and a cutting step of cutting the outermost layer sheet between the fixed absorbent main bodies. A method for producing a disposable absorbent article, comprising: 3. The method for manufacturing a disposable absorbent article according to claim 1, wherein before the fixing step, a first arranging step of arranging a first elastic member on the absorbent body in a flow direction thereof, A second arranging step of arranging a second elastic member in the flow direction on the outermost layer sheet; and arranging the absorbent body substantially 90 ° when arranging the absorbent body on the outermost layer sheet. 3. The method for manufacturing a disposable absorbent article according to claim 2, further comprising a step of inverting the disposable absorbent article.