JPH07255773A - Underpants type disposable paper diaper - Google Patents

Abstract

PURPOSE:To prevent soft feces or the like from leaking from the side edge joint part between a front body part and a back body part of a garment in the underpants type disposable paper diaper. CONSTITUTION:Between a liquid permeable top sheet 1 and a liquid non- permeable back sheet 2, an absorbent 3 is involved while leaving a flap part F composed of the respective sheets 1 and 2 at the parts around legs and when the diaper is extended with a lengthwise center as a boundary in the state of a product, this absorbent is formed in the shape of a sandglass and folded forward and backward. At the same time, folded front body and back body parts F and B of a garment are joined at their both side edges. Then, joint lines 8 at both the side edge parts, where the front body part F and the back body part B of a garment are joined, are continuously formed without leaving any non-joined part at least in the side edge direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pants-type disposable paper diaper, and more specifically, a flap formed between a liquid-permeable top sheet and a liquid-impermeable back sheet at least around the legs by the sheets. The present invention relates to a pants-type diaper in which an absorbent body is included while leaving a part, and an hourglass-shaped article is folded in the front-rear direction and both side edges thereof are joined to each other.

[0002]

2. Description of the Related Art Conventionally, an absorbent body is enclosed between a liquid-permeable top sheet and a liquid-impermeable back sheet, leaving at least a flap portion formed by each sheet at the leg part, and the absorber is used before use. A paper diaper is widely used in which a fastening tape fixed to the back of the body is fastened to wrap the crotch portion of the wearer.

In recent years, however, so-called pants-type diapers have been used for the purpose of facilitating the separation of the diaper or for the purpose of relieving an adult from the work of wearing a fastening tape each time and simplifying the wearing. Is being developed.

As shown in FIG. 15, for example, the pants-type disposable diaper has elastic stretchable members 6 and 7 arranged on the front and rear waist regions on a liquid-impervious backsheet 2 made of polyethylene or the like. The first elastic stretchable member 4 is provided continuously from the front body F end of one leg around the lower part of the product diaper to the front body F end of the other leg, and the rear body B end of one leg. A second elastic stretchable member 5 which is continuous with the other body around the crotch portion of the product paper diaper at the rear body B end of the other leg, and the absorbent body 3 is arranged on the liquid-impervious backsheet 2, and Liquid permeable top sheet 1 on top of this
Are stacked, folded in the front-back direction in a pre-formed hourglass shape, and the folded side edges are fixed by an ultrasonic welding method to obtain a pants-type disposable diaper.

In the above-mentioned pants-type disposable diaper, as a welding pattern when the both side edges of the front body F and the back body B are ultrasonically welded, for example, an actual open flat plate 4-44920.
The welding pattern of FIG. 11 or FIG. 12 is proposed in the publication. The welding pattern shown in FIG. 16 has "-" welding lines arranged in the side edge direction, and the welding pattern shown in FIG. 17 has "." Welding points scattered in the side edge direction. Both welding patterns are intermittent in the side edge direction,
The welding line is discontinuous.

[0006]

However, when the ultrasonic welding pattern is the intermittent joining pattern as described above, when the loose feces excreted around the waist, the intermittent joining is performed. In some cases, it leaked out through the non-welded part of the pattern. When the joining pattern is intermittent, as shown in FIG. 18, a horn 20 that vibrates at a predetermined amplitude, and a rotating anvil 21 having irregularities formed around it to form an intermittent mating pattern. Ultrasonic welding is performed through the joining target portion of the paper diaper between the two, but at this time, the vibrating tip of the horn 20 collides with the uneven portion of the rotating anvil 21 to cause a problem such as damage to the convex portion. Was there.

Therefore, the main object of the present invention is to prevent loose stools and the like from leaking out from the side edge joints of the front body and the back body of the pants-type paper diaper, and to prevent damage to the anvil and to pull the joints. The strength is to be well balanced by ensuring the strength when worn and the tearability when removed.

[0008]

Means for Solving the Problems The above problem is that an absorbent body is enclosed between a liquid-permeable top sheet and a liquid-impermeable back sheet, leaving at least a flap portion formed of each sheet at a leg-surrounding portion. In the product state, when it is deployed with the longitudinal center as a boundary, it forms an hourglass shape, is folded in the front-rear direction, and the folded front body and back body are joined at their side edges to form a pant type. In the disposable paper diaper, it can be solved by forming the joining lines of both side edge portions joining the front body and the back body continuously without leaving a non-joined portion at least in the side edge direction. In this case, it is preferable that the joining line is formed as a pattern-like joining line having a width and the thickness of the joining line is partially changed.

[0009]

In the present invention, the joining lines of both side edge portions where the front body and the back body are joined are continuously formed at least in the side edge direction. Therefore, even when the excrement goes around to the waist, loose feces or the like can be prevented from leaking from the joint portion of the side edge. In addition, when observing in detail the damage of the conventional rotating anvil, when the tip of the horn entered the concave portion of the uneven pattern formed around the anvil, the anvil rotates and the side surface of the convex portion and the horn. It was found that the collision would occur with the tip. Therefore, when the joining line is continuous according to the present invention, the concavo-convex pattern formed on the anvil always has a continuous portion formed in the circumferential direction in the concavo-convex pattern, so that the vibrating horn enters the concave part. And the damage to the anvil due to the reasons mentioned above is eliminated.

In this case, by forming the joining line into a pattern-like joining line having a width, the extension of the welding line per unit length becomes longer than in the case where the joining line is simply formed in a linear shape. The tensile strength is improved. In addition, the tensile strength of the joint can be adjusted by partially changing the thickness of the joint line.

[0011]

EXAMPLES The present invention will be described in detail below based on examples.
1 to 4 show an example of a pants-type disposable diaper structure according to the present invention. Pants type disposable diapers
First, at least the leg part is provided between the liquid-permeable top sheet 1 made of non-woven fabric or the like facing the wearer's skin, the liquid-impermeable back sheet 2 made of polyethylene or the like, and the second back sheet 6 made of non-woven fabric or the like. To each sheet 1,
A semi-rigid absorber 3 mainly containing a cotton-like pulp except for the flap portion FL formed by 2 and provided with an absorbing paper or the like as needed is preliminarily formed into an hourglass shape as shown in FIG. The front diaper is folded in the front-rear direction, and both side edges of the folded front body and the back body are fixed to each other by ultrasonic welding to produce a pants-type disposable diaper having no fastening tape.

More specifically, as shown in FIG. 1, one or a plurality of elastic waist elastic members 6 and 7 are provided on the front part and the rear part of the diaper along the lateral direction, respectively, as the liquid-permeable top sheet 1. It is interposed between the liquid impermeable back sheet 2 and arranged in a stretched state.

Further, one or a plurality of the first elastic expansion / contraction members made of rubber thread or the like, which is continuous from the front end F of one leg around the lower part of the product diaper to the front F end of the other leg and is continuous. 4 is arranged, and is made of rubber thread or the like which is provided if necessary around one leg around the rear body B end around the lower portion (inseam portion) of the product diaper and reaches the other leg around the rear body B end. One or a plurality of second elastic elastic members 5 are arranged. Each elastic elastic member 4, 5
Flap portion F allows the entire leg area to expand and contract
L is fixed to the backsheet 2 in a non-stretchable state so that the absorber 3 is not deformed substantially at the portion where the absorber 3 is located. The elastic expansion / contraction members 4 and 5 are continuous with each other in the leg flap portion FL without intersecting, that is, a loop as if continuous.

Further, the leg part of the first elastic expansion / contraction member 4 extends in the rear body direction from the longitudinal center, and conversely the second elastic expansion / contraction member 5 is shortened. The length L in which the leg part of the first elastic elastic member 4 extends in the rear body direction from the longitudinal center is more preferably 2 cm or more. Further, as described above, the second elastic expansion / contraction members 5 are not essential, but when they are arranged, they should not intersect with each other, and even if they are further separated, the separation distance g is preferably 3 cm or less. If the separation distance g is large, the first elastic expansion / contraction member 4 and the second elastic expansion / contraction member 5 become discontinuous around the legs, which causes lateral leakage. In the above example, the use of both the first and second backsheets 2 and 6 instead of a single backsheet brings about an advantage that the elastic expansion and contraction member can be fixed easily and securely. By using a non-woven fabric as the back sheet 6, the appearance of the product is improved. On the contrary, when the back sheet is made of a single plastic sheet such as a polyethylene sheet, the appearance is bad and the commercial value is low. But,
In this embodiment, this aspect is not necessarily excluded. When using a single backsheet, it is desirable to use a so-called poly-laminated nonwoven fabric, with the nonwoven fabric surface being the outer surface.

The description of the method of manufacturing such a paper diaper and the method of arranging the elastic expansion / contraction members 4, 5, ... Is omitted, but if the pants-type paper diaper described above is obtained, the front-back direction is centered on the center line L. Then, both side edges of the folded front body F and back body B are joined by ultrasonic welding to complete a pants-type disposable diaper as shown in FIG.

By the way, in the present invention, the front body F
The joining line on both side edge portions where the back body B and the back body B are joined is continuously formed without leaving a non-joint portion at least in the side edge direction. In the example of FIG. 3 (an enlarged view of which is shown in FIG. 4), one linear joining line 8a is formed along the side edge direction, and at a predetermined interval along the straight joining line 8a. This is an example in which a large number of branch connecting lines 8b, 8b ... Are formed in a perpendicular shape.

Another example of the continuous joining line shape is a pattern as shown in FIGS. 5 to 9, for example. In the joining line shown in FIG. 5, one straight joining line 9a is formed along the side edge direction, and a large number of branch joining lines 9b, 9b orthogonal to this straight joining line 9a at predetermined intervals.
6 is an example in which the joining line shown in FIG. 6 is an example in which the V-shaped joining lines 10, 10 ... Are continuously formed while wrapping each other, and the joining line shown in FIG. This is an example in which a zigzag mountain wave joining line 11 is used, and the joining line shown in FIG. 8 is an example in which two mountain wave joining lines 12a and 12b are formed in an overlapping manner, and the joining line shown in FIG. 9 is In this example, the wavy joining line 13 is used. Although the present invention does not exclude the case where the joining line is formed by one line, the joining line is formed by forming the joining line in a pattern shape having a predetermined width B as in the above-described example. The tensile strength of the part can be improved.

As an example of the improved joining line shape, for example, a pattern as shown in FIGS. These joining lines are adjusted in tensile strength by changing the thickness of the joining lines. To explain in order,
The joining line shown in FIG. 10 is formed by thinning a straight joining line 14a formed along the side edge direction and thickening a large number of branch joining lines 14b orthogonal to the joining line 14a at predetermined intervals. 11 is an example in which the upper side 15b of the V-shaped bonding line is thicker and the lower side is thinner, and the bonding line shown in FIG. 12 is a zigzag shape. 13 is an example in which one side 16b of the mountain wave joining line is thick and the other side 16a is thin, and FIG. 13 similarly shows one side 17b of the zigzag mountain wave joining line being thick and the other side 17a
Is an example of thinning. Finally, the joining line shown in FIG. 14 is an example in which thick line portions 18b and thin line portions 18a are alternately formed on the wavy joining line.

The ultrasonic horn used for forming these joining lines has at least the pattern width B or more. It is desirable that the specific dimension is 3 mm or more, preferably 5 mm or more. On the other hand, the rotating anvil facing the ultrasonic horn is provided with a concavo-convex pattern corresponding to the bonding line pattern on its peripheral surface. Since it exists, the vibrating horn does not enter the recess, and the anvil is not damaged.

[0020]

As described above in detail, according to the present invention, it is possible to prevent loose stools and the like from leaking from the side edge joints of the front body and the back body of a pants-type paper diaper, and to eliminate damage to the anvil. it can. Also, the tensile strength of the joint portion can be adjusted to an appropriate value that balances the strength when worn and the ease of tearing when removed.

[Brief description of drawings]

FIG. 1 is a development view of a pants-type paper diaper.

FIG. 2 is a cross-sectional perspective view of the relevant part.

FIG. 3 is a product state perspective view of a pants-type paper diaper.

FIG. 4 is an enlarged view of a side edge joint portion.

FIG. 5 is a diagram showing another example of forming a joining line.

FIG. 6 is a diagram showing another example of forming a joining line.

FIG. 7 is a diagram showing another example of forming a joining line.

FIG. 8 is a diagram showing another example of forming a joining line.

FIG. 9 is a diagram showing another example of forming a joining line.

FIG. 10 is a diagram showing another example of forming a joining line.

FIG. 11 is a diagram showing another example of forming a joining line.

FIG. 12 is a diagram showing another example of forming a joining line.

FIG. 13 is a diagram showing another example of forming a joining line.

FIG. 14 is a diagram showing another example of forming a joining line.

FIG. 15 is a development view of a pants-type paper diaper.

FIG. 16 is a diagram showing a bonding pattern in a conventional case.

FIG. 17 is a diagram showing a bonding pattern in a conventional case.

FIG. 18 is a diagram showing a joining procedure by ultrasonic welding.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Liquid-permeable top sheet, 2.6 ... Liquid-impermeable back sheet, 3 ... Absorber, 4 ... 1st elastic expansion / contraction member, 5 ... 2nd elastic expansion / contraction member, 6/7 ... waist elastic expansion / contraction member

Claims (3)

[Claims] 1. An absorbent body is enclosed between a liquid-permeable top sheet and a liquid-impermeable back sheet except at least a flap portion constituted by each sheet at a leg portion, and a longitudinal center in a product state. In a pants-type disposable paper diaper that forms an hourglass when deployed as a boundary, is folded in the front-rear direction, and the folded front body and back body are joined at their both side edges to form a pants-type disposable diaper. The joining lines on both side edges that join the rear body,
A pants-type disposable paper diaper, which is formed continuously without leaving a non-bonded portion at least in the side edge direction. 2. The pants-type disposable paper diaper according to claim 1, wherein the joining line is a pattern-like joining line having a width. 3. The pants-type disposable paper diaper according to claim 1, wherein the joining line is a pattern-like joining line having a width, and the thickness of the joining line is partially changed.