JP3015091B2 - Disposable absorbent article and method of manufacturing the same - Google Patents

Description

The present invention relates to a disposable absorbent article used for infants, adults or incontinent persons, for example, a disposable diaper for infants.

[Conventional technology]

This type of disposable diaper generally includes a liquid-permeable top sheet, a liquid-impermeable back sheet, and a vertically long main body composed of an absorber interposed between these sheets. When worn, it is divided into a dorsal part located on the dorsal side of the wearer and a ventral part located on the ventral side.

In such a disposable diaper, for example, a flat type is known in which a fastening device is arranged on both side edges (side flaps) of a back side and the fastening device is fastened to the abdominal side of the main body when worn. (Japanese Patent Publication No. 52-40267).

Recently, a pair of left and right leg openings and one waist opening are formed by joining and fixing the abdominal part and the back part to each other in a pair of left and right side flaps formed on both sides along the longitudinal direction of the main body. A so-called pants-type disposable diaper has been proposed (JP-A-57-77304). The pants-type disposable diaper is configured so that the leg opening and the waist opening are formed to be stretchable and fit to the body shape, and the wearer himself can usually wear it in a three-dimensional state. It is used for toilet training to promote "diaper release" of infants, or for incontinent persons or for walkable adults (Japanese Patent Application Laid-Open No. 61-207605).

Various proposals have been made for a method for producing this type of pants-type disposable diaper.
And Japanese Patent Application Laid-Open No. 1-292102 discloses a method of cross-flow in which the longitudinal direction of the absorber is perpendicular to the flow direction.
The method can be divided into the longitudinal flow method in which the longitudinal direction of the absorber is the flow direction as shown in JP-A-44364 and JP-T-61-502264.

However, in any of the manufacturing methods, a step of folding an individual product from an expanded state to two and sealing a side flap portion (a step not required for a conventional flat disposable diaper) and the like are required. Have been.

Further, in the conventional manufacturing method, a step of inserting an elongated elastic member in a direction perpendicular to the flow direction of the continuous web is required, but such a step requires complicated and advanced technology, A substantial decrease in productivity has occurred.

Thus, in the pants-type disposable diaper,
There is a problem that productivity is remarkably reduced as compared with the flat type disposable diaper, and the cost has to be increased.

On the other hand, Japanese Patent Publication No. Sho 61-502264 proposes a pants-type disposable diaper with a belt in which an elastic belt is joined to a side flap of a diaper main body and does not require a side seal. Since this pants-type disposable diaper has a relatively simple configuration, it can be manufactured continuously and at a high speed, so that productivity can be improved and cost can be reduced.

[Problems to be solved by the invention]

However, in this pants-type disposable diaper with a belt, since the elastic belt is joined to the flap portion of the main body, the substantial working range of the elastic belt is limited to the range of the wearer's waist side. There is a problem that cannot be reliably held by the wearer.

Furthermore, since the elastic belt is joined to the flap portion, the rigidity is low and the strength is low, so that the side flap portion to which the elastic belt is joined is easily damaged during and during wearing, and the diaper main body is securely attached to the wearer. I can't keep it. In such a case, it is conceivable to provide a reinforcing material for improving the strength, but it is not preferable because the texture is lowered and the cost is increased.

In addition, the elastic member is configured to be joined in the longitudinal direction of the side flap, and in order to obtain a good fit, the elongation of the belt must be set to an extremely high value of about 300%. Processing such an elastic member having a high elongation rate causes many problems such as bonding time and handling in a high-speed production process.

Therefore, an object of the present invention is to provide a disposable absorbent article that can securely hold a diaper body at a crotch part of a wearer and that can sufficiently exhibit a gathering function by an elastic belt, and a method of manufacturing the same. .

[Means for solving the problem]

The present invention has a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorber interposed between these two sheets, and a substantially vertically elongated main body; A pants-type disposable absorbent article formed by the elastic belt and the main body, wherein the elastic belt is joined and fixed to each of both ends in the longitudinal direction of the main body. The abdominal side and the back side of the main body are not joined, and are connected via the elastic belt, and when worn, the annular elastic belt surrounds the waist of the wearer and puts the main body on the wearer. The object has been attained by providing a disposable absorbent article characterized by being held at a crotch part and having gathers having elastic members formed on both sides in the width direction of the main body. Things.

Further, the present invention provides a method for manufacturing the disposable absorbent article in which an annular elastic belt is joined and fixed to both ends of a main body having an absorbent body as a method for suitably manufacturing the disposable absorbent article. A main body supply step of folding a substantially vertically formed main body so that both ends in the longitudinal direction overlap each other, and supplying the main body to a polymerization roll; and a pair of continuous elastic belt bands at predetermined positions of the polymerization roll. An elastic belt band supplying step of supplying the both ends in a stretched state so as to sandwich the both ends, between the pair of elastic belt bands, the both ends of the main body,
A main body joining step of intermittently joining; an elastic belt joining step of joining a pair of opposing elastic belt bands to each other with a predetermined area between the adjacent main bodies; And a cutting step of cutting the joined elastic belt band. The present invention also provides a method for producing a disposable absorbent article.

The method for producing a disposable absorbent article, wherein the elastic belt band supplying step supplies a pair of elastic belt bands arranged in parallel at a predetermined distance from each other; Supply the main body so that both ends in the longitudinal direction are located on the elastic belt band,
A main body joining step of intermittently positioning each end portion on each elastic belt band and joining and fixing; a superimposing step of bending the main body to overlap a pair of elastic belt bands with each other; An elastic belt band joining step of joining the belt bands to each other with a predetermined area between the adjacent main bodies; and a cutting step of cutting a pair of elastic belt bands joined in the joining area. The present invention also provides a method for producing a disposable absorbent article.

[Action]

According to the disposable absorbent article of the present invention, since the annular elastic belt joined and fixed to the main body surrounds the entire waist of the wearer, it is effective not only over the waist side of the wearer but also over a wide range of the abdomen and the back. The elasticity of the elastic belt acts.

Since this annular elastic belt is joined and fixed to the main body, the main body is securely held at the crotch of the wearer, and further,
The gathering function of the elastic belt can be exerted all around the waist.

Further, according to the method for producing a disposable absorbent article of the present invention, the step of providing the annular elastic belt on the absorbent article main body is continuous and simple, so that the disposable absorbent article is produced with high production capacity. be able to.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In this embodiment, a disposable diaper for infants will be described as an example of a disposable absorbent article.

The disposable diaper 1 of the present embodiment, as shown in FIG.
The elastic belt 3 is composed of a main body 2 and an elastic belt 3.
Elastic member 4 contracts to exhibit a pants-like shape.

In the disposable diaper 1, basically, two elastic belts 3 are joined to the main body 2, and each elastic belt 3 has an end portion.
3a, 3b, joined side-by-side to form a side seal portion 3c
And the elastic belt 3 forms an annular shape. A waist opening 6 and a pair of leg openings 7 are formed in the disposable diaper 1 by the ring of the elastic belt 3.

As shown in FIG. 2, the main body 2 has a liquid-permeable top sheet 10 forming a side in contact with the wearer's skin, and a liquid-impermeable liquid sheet corresponding to the top sheet 10. A backsheet 11 and an absorbent body 12 fixed between the two sheets 10 and 11 to absorb excrement are provided. The front part and the back part located on the back side are formed.

The main body 2 includes a pair of front and rear waist flaps 13 extending outward from a back first edge and a ventral second edge in the longitudinal direction of the absorber 12, and both side edges of the absorber 12. A pair of left and right side flaps 14 extending outward from the width direction
And leg portions 15 of a pair of left and right side flaps 14, and an elastic member 4 forming a gather in each of the leg portions 15, and each leg portion 15 is formed with a concave notch.

The elastic member 4 disposed on the leg portion 15 is joined to the main body 2 in a generally stretched state by using a means known in the art such as ultrasonic welding, heat welding, and an adhesive. As the elastic member 4, any material known in the art, such as thread rubber, flat rubber, film-type rubber or tape-like foamed polyurethane, can be used, and one or more elastic members may be used. Generally, the arrangement of the elastic members of the leg portions 15 is symmetric. Further, those having a stress at 150% elongation of 70 to 100 g are particularly preferable. By forming the leg portions 15 in this manner, when the disposable diaper 1 is worn, the elastic member 4 is moved along the edge of each leg opening 7 (see FIG. 1).
That is, the side flaps 15 are arranged at the side edges in the crotch region, and the fit at the leg openings 7 is improved.

The top sheet 10 in the main body 2 of the present embodiment is preferably a liquid-permeable sheet that allows excrement to pass through the absorber 12 and has a feeling close to that of underwear. As such a liquid-permeable sheet, for example, Woven fabrics, nonwoven fabrics, porous films and the like are preferred. In addition, a method of applying a hydrophobic compound such as a silicone oil agent or paraffin wax to the periphery of the top sheet 10 or a method of applying a hydrophilic compound such as an alkyl phosphate ester in advance and washing the periphery with warm water is used. By performing water treatment, it is possible to prevent leakage due to bleeding of urine and the like in the peripheral portion.

In addition, the back sheet 11 used in the present example is a liquid-impermeable sheet having a moisture-permeable property that transmits a stretched stretch obtained by adding a filler to a thermoplastic resin, or a sheet having a feel similar to underwear, such as a film. And a nonwoven fabric or a composite material of a film and a woven fabric.

The absorbent 12 is preferably composed mainly of fibrillated pulp and used in combination with a high-molecular-weight water-absorbing polymer, and is preferably a mixture obtained by heat-treating a mixture of a thermoplastic resin, cellulose fiber and a high-molecular-weight water-absorbing polymer. 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 capable 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. Starch-acrylic acid (salt) graft copolymer, saponified starch-acrylonitrile copolymer,
A crosslinked product of sodium carboxymethyl cellulose, an acrylic acid (salt) polymer and the like are preferable. The shape is preferably an hourglass shape that matches the body shape of the wearer, but may be rectangular.

The elastic belt 3 has a plurality of thread-like elastic gathers on the sheet 16.
The thread-like elastic member 17 is formed by being wrapped around the sheet 16. The elastic belt 3 is joined to the waist flap 13 of the main body 2 over substantially the entire area on the back sheet 11 side in the width direction. Joining and fixing of the elastic member 4 and the elastic belt 3 are obtained by means known in the art such as ultrasonic welding, heat welding, and an adhesive, respectively, as described later.

The elastic belt 3 makes the waist opening 6 elastic throughout, and the pair of leg openings 7 is elasticized by the elastic belt 3 and the elastic member 4. Preferably, the elastic belt 3 surrounding the waist opening 6 is continuously expandable and contractible over the entire circumference thereof, and the elastic belt 3 and the elastic member 4 are connected to each other at the leg openings 7 so as to be expandable and contractible with each other. Is preferred. As a result, the fit of the disposable diaper 1 when worn can be further improved.

The elastic belt 3 can expand and contract in at least one direction,
One direction that can be extended and contracted is a direction around the waist.
The elastic belt 3 and the main body 2 are joined by ultrasonic welding, heat welding,
This is performed when the elastic belt 3 is in the stretched state by a method such as bonding with an adhesive.

The elastic belt 3 is joined and fixed to the longitudinal ends of the main body 2 on the abdominal side and the back side. Specifically, the elastic belt 3 is attached to the waist flap 13 on the abdominal side and the back side.
12 are arranged over the area where they are arranged. The elastic belt 3 is not the top sheet 10 of the main body 2 but the back sheet 11
It is preferable to arrange them.

The joint between the elastic belt 3 and the main body 2 may be substantially non-elastic. For example, a configuration in which the thread-like elastic member 17 is not arranged in this portion may be adopted. In particular, in the case of joining to a region where the absorber 12 is arranged, it is desired to make the absorber inelastic.

It is preferable that the width of the elastic belt 3 is arbitrarily selected between 10 and 150 mm.
It is preferable to be provided to extend from the waist flap 13 by 5 mm or more.

The elastic belt 3 is made of a nonwoven sheet 16 having air permeability.
The thread-like elastic members 17 are joined and fixed in an extended state between the layers. The elastic member 17 is bonded and fixed to the sheet 16 by using an adhesive such as hot melt, ultrasonic welding, or heat welding, which is well known in the art. When an adhesive such as hot melt is used, it is preferable to bond the elastic member 17 after applying it in a stripe shape in a direction perpendicular to the direction in which the elastic member 17 extends in order to form a gather ring neatly.

As the sheet 16 forming the elastic belt 3, in addition to a woven fabric, a nonwoven fabric, a porous film, a moisture-permeable film, and a composite material having a feeling similar to underwear, a material having air permeability is preferable. Further, as the elastic member 17, in this embodiment, a plurality of thread-like elastic members are mentioned, but an elastic film can also be used, and in addition, flat rubber, tape-like rubber, and the like can be used. . The elastic belt 3 is not limited to the above configuration,
Any material can be used as long as it has elasticity in at least one direction, and is preferably a stretchable nonwoven fabric having a feeling similar to underwear and breathability.

When wearing the disposable diaper 1 having the above-described configuration,
As shown in FIG. 1, the main body 2 is expanded in a natural state, and a pair of elastic belts 3 are formed in an annular shape. As a result, a waist opening 6 defined by the pair of elastic belts 3 and a leg opening 7 defined by the side flap 14 and each elastic belt 3 are formed. Thus, the pants type shown in FIG. 1 is formed, a foot is put into the leg opening 7, and the disposable diaper 1 of this embodiment is worn.

In this case, since the elastic belt 3 is formed in an annular shape, the elasticity of the elastic belt 3 acts over a wide range around the waist of the wearer. Furthermore, the gathering function of the elastic belt works around the entire circumference of the waist of the wearer.

Next, a method for manufacturing the above-described disposable diaper will be described.

First, a first embodiment of a method for manufacturing a disposable diaper will be described with reference to FIG.

In addition, since the manufacture of each of the main body 2 and the elastic belt 3 is manufactured by a conventional technique, a detailed description of these manufacturing steps will be omitted.

In the previous step shown in FIG. 3, the main body 2 is divided into individual main bodies 2 from a continuous belt-like body, and is intermittently polymerized with the back sheet 11 as an outer surface in a state of being folded into two. It is sent to rolls 20a and 20b.

On the other hand, the elastic belt bands 21a and 21b are folded by the polymerization rolls 20a and 20b on the polymerization rolls 20a and 20b from two directions (up and down directions in FIG. 3) intersecting the conveying direction of the main body 2. The main body 2 is supplied so as to sandwich the end of the main body 2 from above and below. The elastic belt bands 21a and 21b are formed by continuously forming the elastic belt 3 integrally.

Polymerized rolls in the transport direction of the elastic belt bands 21a and 21b
Adhesive coating devices 22a and 22b are provided just before 20a and 20b. The elastic belt bands 21a and 21b are
Adhesives 23a and 23b are intermittently applied to predetermined positions by a and 22b, and sent to polymerization rolls 20a and 20b, respectively, in an extended state.

Then, the elastic belt bands 21a and 21b are
Are placed on each other, but are arranged so as to sandwich the main body 2 in a portion where the adhesive is applied. That is, both ends of the front side and the back side of the main body 2 are elastic belt bands 21 in an extended state.
a and 21b are polymerized in a sandwiched state, and the adhesive 23
The main body 2 is joined and fixed to the elastic belt bands 21a and 21b by the a and 23b to form a continuous web of the disposable diaper 1. However, the elastic belt bands 21a, 21b must not be adhered to each other by the adhesives 23a, 23b.

Thereafter, the continuous web is sent to the ultrasonic unit 24 via a feed roll, a nip roll and the like (not shown). The ultrasonic unit 24 includes an ultrasonic transmitter 25 and an anvil 26 and welds the side portions of the elastic belt 3. That is, the elastic belt bands 21a and 21b are welded to each other at an intermediate position between the adjacent main bodies 2 to form the side seal portions 3c. At this time, a pattern is formed on the anvil 26 so that the welding of the elastic belt is performed intermittently.

After the side seal is finished, the web of the main body 2 is cut into individual disposable diapers 1 by a final cutter unit 29 including cutter rolls 27 and 28. The cutting is performed in the region of the side seal portion 3c, preferably in a substantially central portion. In addition, the ultrasonic seal is performed so as to obtain an appropriate seal strength and seal width so that the seal portion does not peel off immediately after cutting.

By the above-described process, a disposable diaper 1 with an elastic belt as shown in FIG. 1 is obtained.

This embodiment is only one embodiment of the method of the present invention. Therefore, for example, in joining the elastic belt 3 and the main body 2, the adhesive 15 is not limited to being applied intermittently to the elastic belt 10, and any known means such as adhesion can be used. Further, in this embodiment, the stretchable portion of the elastic belt can be intermittently positioned, and a substantially inelastic portion can be applied to the joint portion with the main body 2.

According to the first embodiment, since the production of the above-mentioned disposable diaper can be easily and continuously produced, the production capacity of the disposable diaper can be increased.

Next, a second embodiment of the method for manufacturing a disposable diaper will be described with reference to FIG.

Also in the second embodiment, the description of the respective steps of forming the main body 2 and the elastic belt 3 is omitted as in the first embodiment.

After the predetermined material has been polymerized, the main body web 30 is intermittently applied to the back sheet 11 side by the adhesive application device 31.
Is applied and sent to the reversing unit 33. The reversing machine unit 33 includes a reversing machine 34, a polymerization roll 35 for holding the elastic belt bands 21 a and 21 b on the reversing machine 34, and a cutter 36 for cutting the main body web 30 to form the main body 2. .

Although not shown, the reversing device 34 includes arms extending radially around the axis, and a support head at the end of each arm. The support head is provided with an anvil corresponding to the cutter 36. The support head is provided with a mechanism for transporting the support head by reversing about 90 ° before reaching the polymerization roll 35 via the cutter 36.

The main body member web 30 sent to the reversing machine unit 33 is supported by the support head, and is sequentially cut by the cutter 36 into individual main bodies 2 at a cutting virtual line 37. The imaginary cutting line 37 is located substantially in the middle of the portion where the adhesive 32 is applied.

The support head is equipped with some holding means such as a vacuum or a mechanical chuck. In this embodiment,
Assuming that the suction support is used, each of the suction-supported main bodies 2 includes an elastic member 4 disposed on the main body 2 (see FIG. 2).
While being kept in a plane shape without being affected by the above, the sheet is inverted by about 90 ° with respect to the flow direction and sent to the polymerization roll 35.

On the other hand, one stretched elastic belt band 21 in the extended state is sent to the polymerization roll 35 in the stretched state, and is divided into two elastic belt bands 21a and 21b by the slitter 38. The slit may have a linear shape, but in the present embodiment, the product is formed into a curved line with one cycle per product, and the wide part of the elastic belt becomes a side elastic belt in a product state, and is worn. Follow-up ability. The elastic belt bands 21a, 21b after the slit are separated by rolls 39, 39 and are in phase. Then, it is sequentially sent to the polymerization roll 35 while maintaining a constant interval.

In the polymerization roll 35, the main body 2 and the elastic belt bands 21a and 21b are polymerized to form a continuous web of the disposable diaper 1.

The elastic belt bands 21a, 21b and the main body 2 are joined together by an adhesive 32 applied by an adhesive applying device 31 by a polymerization roll 35.

After joining, the disposable diaper web is folded in step 41 such that the topsheet 10 is on the inside and the elastic belt bands 21a, 21b overlap. The folded disposable diaper web is subjected to an elastic belt band in the side sealing process 42.
A side seal portion 21c is provided on each of 21a and 21b, cut by a final cutter 43, and the side seal portion 3c (first
The individual disposable diaper 1 (see the figure) is formed.

In the second embodiment, as described above, the disposable diaper 1 can be manufactured at a low cost without wasting material, since the width of the elastic belt on the side portion is formed relatively wide, and as described above. Extremely effective.

The present invention is not limited to the above-described examples or embodiments, and can be variously modified without departing from the gist of the present invention.

For example, a plurality of elastic belts 3 may be arranged on one side (however, the belly side and the back side are arranged symmetrically). In this case, the elastic belts forming the leg opening 7 and the waist opening 6 are different from each other. By changing the setting of the elongation rate, the fit can be further improved.

Further, it is preferable that a tearing guide is disposed adjacent to the side seal portion 3c so that the elastic belt in the disposable diaper 1 of the present invention can be easily peeled off by a wearer. This tear guide means is a cut guide line, a seal part, or a part capable of easily tearing a part of the elastic belt 3, while having a strength not torn or torn during wearing. It has.

〔The invention's effect〕

ADVANTAGE OF THE INVENTION According to the disposable absorbent article of this invention, a diaper main body can be reliably hold | maintained at a crotch part of a wearer, and the gathering function by an elastic belt can fully be exhibited.

Further, according to the method for producing a disposable absorbent article of the present invention, the above-mentioned disposable absorbent article can be suitably produced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a free state of a disposable diaper according to one embodiment of the present invention, FIG. 2 is a development view of the disposable diaper shown in FIG. 1, and FIG. FIG. 4 is a perspective view showing one embodiment, and FIG. 4 is a perspective view showing another embodiment of a method for manufacturing a disposable diaper. 1; disposable diaper, 2; body 3; elastic belt, 10; topsheet 11; backsheet, 12; absorber

Claims (5)

(57) [Claims] 1. A substantially vertically elongated main body having a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorber interposed between the two sheets. A disposable absorbent article of a pants type formed by the elastic belt and the main body, wherein the elastic belt is fixedly joined to each of both ends of the main body in the longitudinal direction. The abdominal side and the back side of the main body are not joined and are connected via the elastic belt, and when worn, the annular elastic belt surrounds the waist of the wearer and the wearer wears the main body. A disposable absorbent article characterized by being held at the crotch part of the body and having gathers having elastic members formed on both sides in the width direction of the main body. 2. The disposable absorbent article according to claim 1, wherein said absorbent body is arranged inside the peripheral edge of said main body, and said absorbent body is not arranged at said both ends. Goods. 3. The elastic belt according to claim 1, wherein the elastic belt has a width exceeding the edge of each end at a portion fixedly joined to both longitudinal ends of the main body. The disposable absorbent article according to (1). 4. A method of manufacturing a disposable absorbent article in which an annular elastic belt is joined and fixed to both ends of a main body having an absorbent body, wherein the substantially vertically elongated main body is provided with both ends in the longitudinal direction. A main body supply step of folding the stack to overlap and supplying the same to the polymerization roll; and an elastic belt band for supplying a continuous pair of elastic belt bands to a predetermined position of the polymerization roll so as to sandwich the both ends in an extended state. A supply step, a main body joining step of intermittently joining both ends of the main body between the pair of elastic belt bands, and a pair of opposing elastic belt bands, the opposing elasticity between the adjacent main bodies. A disposable absorption device comprising: an elastic belt joining step of joining belts together with a predetermined area; and a cutting step of cutting the joined elastic belt bands in the joining area. Method of manufacturing an article. 5. The method for producing a disposable absorbent article according to claim 1, wherein an elastic belt band supplying step of supplying a pair of elastic belt bands arranged in parallel at a predetermined interval from each other. A main body which supplies the main body so that both ends in the longitudinal direction of the main body formed in a vertically elongated manner are positioned on the elastic belt band, and which jointly fixes the both end portions by intermittently locating the both ends on the elastic belt band. A joining step; a superposing step of bending the main body to overlap the pair of elastic belt bands; and an elastic belt joining the pair of superposed elastic belt bands to each other with a predetermined area between the adjacent main bodies. A method for producing a disposable absorbent article, comprising: a band joining step; and a cutting step of cutting a pair of elastic belt bands joined in the joining region.