JP2009056156A - Elastic part forming method in absorbent article and disposable diaper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an art of easily adjusting a stretching rate in a fixed state of respective elastic members. <P>SOLUTION: A plurality of elongate elastic members 2 are aligned in parallel and clamped between an inner sheet 1A and an outer sheet 1B with their stretched state in the longitudinal direction, the inner sheet 1A and the outer sheet 1B are ultrasonically welded near the width-directional both ends of the respective elastic members 2, and then tension applied to the elastic members 2 is released to expand the elastic members 2 by contraction. When the elastic members 2 are clamped and fixed between the weld portion 3 near the width-directional one end of the elastic members and the weld portion 3 near the width-directional other end, an interval 3d between the weld portions 3 in the width-directional both sides of one elastic members 2 is formed different from an interval 3d between the weld portions 3 in the width-directional both sides of the other elastic members 2. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a stretchable part forming method and a disposable diaper in an absorbent article.

For example, in a pants-type disposable diaper, as shown in FIGS. 1 and 2, shirring may be formed around the abdomen and waist as an expansion / contraction part in order to add a fitting function (see, for example, Patent Document 1). This shearing is performed by sandwiching a plurality of elastic members such as thread rubber between a plurality of breathable / water-repellent nonwoven fabrics constituting the exterior sheet, and bonding the elastic member and the exterior sheet to an adhesive such as hot melt. It is formed by fixing with.
As such a shearing formation method, an adhesive such as hot melt is applied to either the elastic member or the exterior sheet or both the elastic member and the exterior sheet online, and then the elastic member is sandwiched between the nips. It is common to fix by doing (for example, refer patent documents 2-4).
In addition, a technique for fixing an exterior sheet and an elastic member in a state of being mechanically sandwiched and crushed has been proposed (see Patent Document 5).
JP 2002-172132 A JP 2000-26015 A JP 2002-273808 A JP 2004-229857 A JP 2004-330777 A

By the way, when such an elastic member around the waist is provided, it is preferable to adjust the stretch rate in a fixed state (hereinafter, also simply referred to as the stretch rate) for each elastic member in order to improve fit to the body. Specifically, the stretch rate is changed between the abdominal elastic member and the back elastic member, or the stretch rate is changed between the elastic member located near the waist opening and the elastic member located near the crotch. It is desirable.
However, when the elastic member is set individually by the conventional method of fixing the elastic member with a hot melt adhesive, it is necessary to individually adjust the elastic member's extension rate. There is a problem in that the adjustment work in is complicated.
Then, the main subject of this invention is providing the technique which can adjust the expansion ratio in the fixed state of each elastic member more easily.

The present invention that has solved the above problems is as follows.
<Invention of Claim 1>
A plurality of elongated elastic members are stretched in the longitudinal direction and are arranged in parallel between the inner sheet and the outer sheet, and the inner sheet and the outer sheet are joined in the vicinity of both ends in the width direction of the elastic members. After that, the tension applied to the elastic member is released to expand the diameter of the elastic member by contraction, and the elastic member is connected between the joint near the one end in the width direction and the joint near the other end in the width direction. An elastic part forming method for fixing with an elastic member in between,
The distance between the joint near one end in the width direction of some elastic members and the joint near the other end in the width direction, and between the joint near one end in the width direction of the other elastic member and the other end in the width direction. Make the gap with the joint different,
A stretchable part forming method characterized by the above.

<Invention of Claim 2>
The plurality of elastic members have the same stretch rate when sandwiched between the inner sheet and the outer sheet, and have the elastic member expanded in diameter by contraction. The stretchable part forming method according to claim 1, wherein the stretch rate of some of the elastic members is different from the stretch rate of the other elastic members.

(Function and effect)
In the stretched state where tension is applied to the elastic member, when the inner sheet and the outer sheet are joined in the vicinity of both ends in the width direction of the elastic member and then the tension is released (no tension), the elastic member expands due to contraction. In the extended state, the elastic member is sandwiched and fixed from both sides in the width direction by the joint portion between the inner sheet and the outer sheet. Therefore, the expansion ratio in the fixed state of the elastic member depends on how much the elastic member contracts and expands. The present invention uses this principle to adjust the stretch rate of the elastic member in the fixed state. By changing the interval between the joints located on both sides of each elastic member, the stretch rate of each elastic member can be arbitrarily set. Is set to Specifically, the narrower the gap between the joint portion on one side in the width direction of the elastic member and the joint portion on the other side, the higher the expansion rate is fixed, and the joint portion on one side and the other side in the width direction of the elastic member. The wider the gap, the lower the expansion rate. By using this method, it is possible to make the elongation rates of the elongated elastic members different from one to another after releasing the tension even if all the elongation rates of the plurality of elongated elastic members are the same. This eliminates the need for complicated adjustment work. Furthermore, if the same thing is used for several elongate elastic members, since the replacement | exchange time of a raw material roll can be made the same at the time of manufacture, work efficiency will improve.

<Invention of Claim 3>
The interval between the joint portion in the vicinity of one end portion in the width direction of each elastic member and the joint portion in the vicinity of the other end portion in the width direction is 10 to 90% of the width of the elastic member in the non-stretched state. 3. The stretchable part forming method according to 2.

(Function and effect)
If the distance between the joint near the one end in the width direction of the elastic member and the joint near the other end in the width direction is less than 10% of the width of the elastic member in the non-stretched state, the elastic member is included in the joint. Manufacture becomes extremely difficult, such as the possibility of joining, and if it exceeds 90%, the force for sandwiching the elastic member between the joints becomes weak, and the elastic member may come out from between the joints. The non-stretched state means a state where no tension is applied to the elastic member.

<Invention of Claim 4>
The stretchable part formation according to any one of claims 1 to 3, wherein the inner sheet and the outer sheet are joined by intermittently welding the inner sheet and the outer sheet along the elastic member. Method.

(Function and effect)
As described above, by adopting welding between the inner sheet and the outer sheet without using an adhesive for joining the inner sheet and the outer sheet, the air permeability, the softness, the stretchability, and the like are improved. The welding can be ultrasonic welding or heat welding. However, it is more preferable to use ultrasonic welding because the influence of heat and pressure applied to the elastic member and the peripheral portion of the sheet is less in ultrasonic welding than in thermal welding.

<Invention of Claim 5>
An exterior sheet having at least a waistline portion and having a portion in which the inner layer and the outer layer are bonded to the waistline portion;
An interior body provided on the body side of the exterior sheet for absorbing and holding an object;
Between the inner layer and the outer layer in the waist portion, a plurality of elongated elastic members are provided in parallel in a state of extending along the waist direction,
The inner layer and the outer layer are bonded to each other on both sides in the width direction of each elastic member without using each elastic member, and a bonded portion is formed.
Each of the elastic members is a disposable diaper that is sandwiched and fixed between a joint portion on one side in the width direction and a joint portion on the other side in the width direction,
The distance between the joint portion on the one side in the width direction and the joint portion on the other side in the width direction of some of the elastic members, and the joint portion on the one side in the width direction and the joint portion on the other side in the width direction of the other elastic members. The interval is different,
A disposable diaper characterized by that.

(Function and effect)
By making the interval between the joint portions located on both sides of each elastic member different, the stretch rate of each elastic member can be arbitrarily set, and the fit to the body can be improved.

  According to the present invention, there are advantages such that the expansion ratio of each elastic member in a fixed state can be more easily adjusted in the stretchable part.

Embodiments of the present invention will be described below.
FIG. 1 shows an example of an expansion / contraction part forming apparatus. An ultrasonic vibration source 5, a horn 6 connected to the ultrasonic vibration source 5 and increasing the vibration amplitude from the ultrasonic vibration source 5, and the horn 6 And an anvil roll 7 disposed opposite to each other. The ultrasonic vibration source 5 is fixed to a pressure arm (not shown), and the height can be adjusted. Further, before and after the anvil roll 7, guide rolls 8 and 9 are provided for preventing loosening of the continuous sheet 4 with the elastic members 2, 2.
Although not shown, the tension of the continuous sheet 4 is kept constant outside the guide roll in order to prevent looseness of the continuous sheet 4 with the elastic members 2, 2. Therefore, it is more preferable to use tension control such as a step roll.

  The continuous sheet 4 is formed by laminating and fixing two or three or more breathable / water-repellent nonwoven fabrics, and a plurality of elastic sheets arranged in parallel between the inner sheet 1A and the outer sheet 1B. The members 2, 2 ... are sandwiched. As the nonwoven fabric, a polypropylene resin (PP), a polyethylene resin (PE), a polyethylene terephthalate resin (PET), a composite of these, or the like can be used. Furthermore, the continuous sheet 4 is not limited to a nonwoven fabric, and a film made of polyethylene resin or the like can be used as long as it can be fixed by heat welding or ultrasonic welding, or a combination of a nonwoven fabric and a film can be used.

  The elastic member 2 may be a known elastic yarn as long as it has elasticity and can be fixed in tension with the surrounding nonwoven fabric. Materials include natural rubber, polyurethane, block polyether amide, block polyether ester, polyurethane urea, elastic polyolefin, thermoplastic styrene-butadiene-styrene (SBS), styrene-isoprene-styrene, styrene-ethylene / propylene-styrene, Styrene-ethylene-butadiene-styrene (SEBS), hydrogenated styrene-butadiene-rubber and elastomers based on these and other polymers such as polystyrene or polyolefins can be used. Also, elastic yarns from segmented polyester or polyether urethane-urea can be used. The thickness of the elastic member 2 can be set arbitrarily. Further, the cross-sectional shape is not limited to a circle, but can be freely selected from an ellipse, a rectangle, and other geometric shapes.

  As shown in FIG. 2, a plurality of projections 7A, 7A... Are formed on the outer peripheral surface of the anvil roll 7, and a predetermined depth is formed between these projections 7A, 7A. A groove having a thickness is formed. When the continuous sheet 4 is ultrasonically welded by the horn 6 and the anvil roll 7, as shown in FIGS. 2 and 3, the horn 6 and the projection 7A of the anvil roll 7 are used in the vicinity of both ends in the width direction of the elastic member 2. The inner sheet 1A and the outer sheet 1B are sandwiched and welded (corresponding to the joint portion of the present invention, hereinafter referred to as a welded portion 3), and a groove formed between the projection 7A and the projection 7A In the portion, the inner sheet 1A and the outer sheet 1B are not welded, and the elastic member 2 is received without being fixed between both sheets in the groove. In the figure, the inner sheet 1A is located at the upper part and the outer sheet 1B is located at the lower part. However, the inner sheet 1A may be located at the lower part and the outer sheet 1B may be located at the upper part. The same applies to this point.

  The distance 7cd between the protrusion 7A in the width direction (axial direction) of the anvil roll 7 and the protrusion 7A is equal to the distance 3d between the welded portions 3 on both sides in the width direction of the elastic member 2, and as shown in FIG. It is made wider than the width (cross-sectional outer diameter) 2w of the elastic member 2 in the stretched state in which tension is applied in the direction. In the disposable diaper, the elastic member 2 is generally fixed to the sheets 1A and 1B in a state in which a polyurethane thread rubber having a thickness of about 470 to 940 dtex is stretched by 2 to 3 times. Then, it is preferable to set the space | interval 3d of the space | interval 3d of the welding part 3 to 1.0 to 1.1 times the width | variety (thread diameter in the case of a rubber thread) of the elastic member 2 in an expansion | extension state, and also a non-expansion state It is preferable to set the width of the elastic member 2 at 0.4 to 0.7 times the width of the elastic member 2 (thread diameter in the case of rubber thread).

When the frictional resistance of the elastic member 2 and the sheets 1A and 1B is high, or when the elastic member 2 has a low elongation rate, the interval 3d between the welded portions 3 is 1.3 times the outer diameter of the elastic member 2 in the expanded state. Although it can be expanded to the extent, 1.0 to 1.2 times is preferable in the usual case, and 1.0 to 1.1 times is particularly preferable. In this case, the holding force (friction resistance) becomes higher as it becomes closer to 1 times, but it is preferable to make the elastic member 2 wider than 1 time because the elastic member 2 may be cut by ultrasonic welding. Needless to say, the groove width needs to be within the above range and narrower than the diameter of the elastic member 2 when relaxed. In order to ensure the holding force, the distance 3d between the welded portions 3 is desirably 70% or less of the diameter of the elastic member 2 in the non-expanded state.
Characteristically, the distance 7cd between some of the protrusions 7A, 7A ... and the distance 7cd between the other protrusions 7A, 7A ... are different, and the width direction of some of the elastic members 2 during the ultrasonic welding described above. The interval 3d between the welded portions 3 on both sides and the interval 3d between the welded portions 3 on both sides in the width direction of the other elastic members 2 are different.

  As shown in FIG. 2, the groove between the protrusions 7A, 7A... Is for accommodating the elastic member 2 so that the elastic member 2 is not narrowed by the protrusion. Therefore, the interval between the adjacent grooves coincides with the arrangement interval between the adjacent elastic members 2, 2. Further, the depth of the groove between the protrusions 7A, 7A... (The height of the protrusions 7A to 7C) may be a depth that allows the elastic member 2 to be accommodated and a depth that does not allow the continuous sheet 4 to sag excessively. It is desirable that the dimensions be similar to the groove width. Specifically, the depth of the groove is preferably 0.9 to 1.2 times the outer diameter of the cross section of the stretched elastic member 2. The most preferable range is 1.0 to 1.1 times. If it is smaller than 1.0 times, the force for holding the elastic member 2 becomes strong, but the entire elastic member 2 may be welded. Moreover, it is not preferable that the depth of the groove is larger than the outer diameter of the cross section of the elastic member 2 when not stretched. When the sheets 1A and 1B have a property of being easily distorted in the CD direction (axial direction of the anvil roll) like a nonwoven fabric, if the groove is too deep, the sheets 1A and 1B are stretched and distorted during pinching, There is a possibility that sufficient force to sandwich the elastic member 2 cannot be obtained.

  As described above, between the anvil roll 7 in which the protrusions 7A are arranged in a lattice and the horn 6, the inner sheet 1A and the outer sheet 1B of the continuous sheet 4 are narrowly pressed while the elastic member 2 is in the groove. Then, ultrasonic welding is performed by the projection 7A and the horn 6. As a matter of course, since the elastic member 2 is accommodated in the groove, the tensioned elastic member 2 is not compressed by the protrusion 7 and the horn 6. As shown in FIG. 3, since this welding is performed in a state where tension is applied to the elastic member 2 and in the vicinity of both end portions in the width direction of the elastic member 2, when the tension is released thereafter (no tension) As shown in FIG. 4, the elastic member 2 is sandwiched and fixed from both sides in the width direction by the welded portion 3 between the inner sheet 1 </ b> A and the outer sheet 1 </ b> B in a stretched state in which the elastic member 2 expands due to contraction. As a result, the elastic member 2 having a narrow interval 3d between the weld portions 3 on both sides in the width direction is fixed at a high elongation rate, and the elastic member 2 having a wide interval 3d between the weld portions 3 on both sides in the width direction is fixed at a low elongation rate. Become so. By using this method, even if all the elongation rates of the plurality of elongated elastic members 2 are the same, the elongation rates of the elongated elastic members 2 in the fixed state after releasing the tension are made different one by one. This eliminates the need for complicated adjustment work. Further, it is not necessary to provide different driving devices for each of the elongated elastic members 2, and the tension adjustment can be concentrated on the arrangement pattern of the projections of the anvil roll, so that the manufacturing equipment can be made compact. Furthermore, if the same thing is used for the plurality of elongate elastic members 2, the replacement time of the raw material roll becomes the same at the time of manufacture, so that the working efficiency is improved.

Further, since the elastic member 2 is fixed only by the frictional force with the inner and outer sheets 1A and 1B without using an adhesive, it is possible to prevent the elastic member 2 from being deteriorated by the adhesive. Furthermore, since the elastic member 2 is not bonded, air permeability and softness can be improved. Furthermore, since the material itself is melted and bonded, the fluctuation cost of hot melt can be reduced, and machine troubles caused by hot melt can be prevented. Similar advantages can be obtained by using heat welding by heat embossing instead of ultrasonic welding.
It is sufficient that the elastic member 2 has an expansion ratio before fixing that is higher than that of the fixed state. However, if the elastic member 2 is too high, the tension releasing force becomes too strong. It is preferably 1.50 times. In addition, by designing the elastic members 2 to have the same pre-fixing tension, it is possible to obtain a stretchable part that can be easily adjusted, but by making some or all of the pre-fixing tensions different, It is possible to design a complicated (high degree of freedom) stretchable part.

The arrangement of the protrusions is not limited to the lattice shape, but may be a staggered array of protrusions 7C as shown in FIG. Moreover, if the distance (groove width) 7cd between the protrusions 7A to 7C and the protrusions 7A to 7C is within the above range with respect to the cross-sectional outer diameter of the elastic member 2 in the stretched state, the protrusions 7A to 7A of the anvil roll 7 will be described. The array pattern of 7C is not limited to a lattice shape or a zigzag shape, and may be another pattern.
The shape of each of the protrusions 7A to 7C is circular in the illustrated example, but may be a polygon such as a triangle or a quadrangle, or a pattern such as an ellipse, a star, or a heart. If a shape without corners such as a circle or an ellipse is used, a soft texture can be obtained. If a cornered shape is used and the corners are disposed so as to face the elastic member 2, the elastic member 2 can be more easily removed (a phenomenon in which the elastic member 2 contracts while being displaced without being fixed by the sheets 1A and 1B). It can be surely prevented. In this case, the pull-in is reduced as the angle facing the elastic member 2 is an acute angle. The angle of the angle facing the elastic member 2 is preferably 15 to 15 degrees, and particularly preferably 30 to 90 degrees.

In the case of a circular shape, the size of the protrusions 7A to 7C is preferably 0.2 to 4 mm, more preferably 0.3 to 5 mm, and particularly preferably 0.3 to 1 mm. Most preferably, it is 0.3 to 0.6 mm. The smaller the diameter, the better the texture of the sheet. However, if it is too small, the bonding strength between the sheets 1A and 1B cannot be sufficiently obtained. Conversely, when the protrusions 7A to 7C are too large, the texture is lowered. For other shapes, the area in the case of a circle may be set as a reference, and the dimensional ratio between length and width may be extremely different. Area of the tip surface of the projection 7A~7C is preferably a 0.03~80mm ^2, more preferably from 0.07~5mm ^2, particularly preferably in the range of 0.07~0.8mm ^2, Most preferably, it is 0.07 to 0.3 mm ² .
The distance 7 md between the protrusions 7 </ b> A to 7 </ b> C in the MD direction (the circumferential direction of the anvil roll and the longitudinal direction of the elastic member 2) can generally be about 0.3 to 5 mm, but is not particularly limited to this. Alternatively, the protrusions 7A to 7C may be continuous in the MD direction in a strip shape (line shape). If the texture of the sheets 1A and 1B, the adhesive strength between the sheets 1A and 1B, and the fixing of the elastic member 2 are balanced, for example, if the protrusions 7A to 7C have a circular shape with a diameter of 0.3 to 0.6 mm, The distance 7 md in the MD direction of the protrusions 7 </ b> A to 7 </ b> C may be about 0.3 to 1.0 mm, and the distance 7 cd in the CD direction (axial direction of the anvil roll) may be about 0.3 to 1.5 mm.

When the arrangement of the protrusions 7A to 7C is the above-described lattice arrangement, the protrusions 7A to 7C are located on both sides in the width direction at the same portion in the longitudinal direction of the elastic member 2, so that a high holding force is obtained. However, there is a high possibility that the elastic member 2 is welded or cut. On the other hand, when the staggered arrangement is used, the possibility that the elastic member 2 is welded or cut decreases, but the holding force also decreases. In the staggered arrangement, the rows of protrusions arranged in the MD direction at a predetermined periodic interval are provided with a predetermined interval in the CD direction, and the phase of the arrangement period of the protrusions in each row is shifted from the adjacent row. Yes, it may be arranged so that the phase is shifted by 1/2 with respect to the adjacent protrusion rows as shown in the example, but in order to make it closer to the lattice arrangement, for example, the phase is shifted by 1/4. May be. By adjusting the phase shift between 0 and 1/4, the holding force of the elastic member 2 and the avoidance of cutting can be balanced.
In order to obtain a soft texture, the area ratio of the welded part 3 in the fixed area of the elastic member 2 is preferably 40% or less, particularly preferably 30% or less, and 5% or less. Is most preferred. Further, in the non-fixed region of the elastic member 2, the area ratio of the welded portion 3 needs to be at least 2% in order to maintain the bonding strength of the sheets 1A and 1B. In the fixed region of the elastic member 2, the sheet bends due to the contraction of the elastic member 2, so that a bonding strength equal to or higher than the non-fixed region of the elastic member 2 is required. Therefore, in the fixed region of the elastic member 2, the area ratio of the welded portion 3 is preferably 5% or more, and more preferably 4% or more.

  As a method of releasing the tension of the elastic member 2, when the elastic member 2 is continuously fixed to the sheets 1A and 1B, it can be performed by cutting the sheets 1A and 1B with the elastic member 2 interposed therebetween. When the elastic member 2 is intermittently provided in the direction along the longitudinal direction of the elastic member 2 (in the illustrated embodiment, the line flow direction), the elastic member 2 is continuously attached to the two sheets 1A and 1B. After sandwiching the two sheets 1A and 1B, as shown in FIG. 6, by cutting the elastic member 2 in the non-stretchable region X2 (between the stretchable region X1) located between the stretchable regions X1, It is also possible to release the tension of the elastic member 2 and fix the elastic member 2 to both sheets 1A and 1B at a predetermined elongation rate. At this time, since the welded portion 3 is provided at least in a range corresponding to the stretchable region, when the elastic member 2 in the non-stretchable region is cut and the tension is released, a predetermined stretch rate is obtained in the stretchable region. It is fixed with. Such a form is suitable and often used in providing a non-stretchable region in a portion overlapping with the absorber when providing the elastic member 2 that enhances the fit of the waistline in a pants-type disposable diaper described later. In the illustrated form, it is assumed that the range corresponding to the non-stretchable region is cut by heat embossing with a large number of fine protrusions, but a large number of fine regions are defined for the range corresponding to the non-stretchable region. It is also possible to adopt a method of making a partial cut. Since such a cutting method of the elastic member 2 is a known method as shown in Patent Document 3, detailed description thereof is omitted. When the elastic member 2 is cut by heat embossing with such fine convex portions, the bonding of the sheets 1A and 1B is performed by heat embossing for cutting the elastic member 2 at the non-stretchable portion, Since the expansion / contraction part is formed by welding for sandwiching and fixing the elastic member 2, it is not particularly necessary to use an adhesive for the expansion / contraction part and the non-expansion / contraction part. However, the end portion of the cut elastic member 2 moves toward the inside of the region where the welded portion 3 is formed (so-called pull-in) because the elastic member 2 is relaxed by a certain amount by releasing the tension. Considering this movement distance, if an intermediate region is provided between the arrangement range of the welded portion 3 and the arrangement range of the convex portion, it becomes “welded portion forming region = extension / contraction region”, so that the design of the processing equipment is easy. .

Moreover, you may use the method of giving a heat embossing process and cutting | disconnecting by the 1 or several protrusion in the center of a non-expanding-contraction part as shown by patent document 2. FIG. When the elastic member 2 is cut by the central ridge as described above, or when the elastic member 2 is cut by the above-described fine cutting, the elastic member under extension is particularly shown in Patent Document 4. It is preferable to apply the adhesive so weakly that 2 cannot be fixedly held to form a “weakly bonded portion” because the sheets 1A and 1B can be bonded to each other at the non-stretchable portion. The “weakly bonded portion” can also be applied to the bonding of the sheets 1A and 1B in the intermediate region described above.
The stretchable part forming method and its equipment according to the present invention are not limited to stretchable parts such as shirring and barrier cuffs, gasket cuffs, etc. in pants-type disposable diapers, but also waist gathers, barrier cuffs, gasket cuffs of tape-type disposable diapers, The present invention can also be applied to the formation of stretchable parts such as stretchable tapes, and can also be applied to the formation of stretchable parts such as barrier cuffs and gasket cuffs in general absorbent articles including napkins and the like.

  7 to 17 show an application example to a pants-type disposable diaper, in which the above-described stretchable part forming method is applied when manufacturing an exterior sheet. This pants-type disposable diaper has an abdominal exterior sheet 12F that covers the abdominal side of the wearer's waist and a back exterior sheet 12B that covers the dorsal side, on both side edges in the width direction of the abdominal exterior sheet 12F. The joining portion 12A and the joining portions 12A on both side edges in the width direction of the back exterior sheet 12B are joined by heat sealing, ultrasonic welding, or the like to form the cylindrical waistline portion 100. When the backside exterior sheet 12B extends below the joining portion 12A as in the illustrated embodiment, the backside sheet is subjected to processing such as heat sealing integrally in the vertical range including up to this portion. An extended welded portion 12E can be provided in the extended portion 14. By providing the extended welded portion 12E, it is possible to prevent the second elongated elastic member 16 from being pulled in the backside extended portion 14 described later. In this case, considering the ease of breakage of the side portion, the joining portion 12A is generally composed of a collection of small welded portions, and is generally a joining pattern having a low ratio of the welding area in the joining portion 12A. Since it is not necessary to consider the ease of tearing in the welded portion 12E, the second elongated elastic member 16 is surely welded and fixed by increasing the ratio of the welded area of the welded pattern to the welded portion 12A. Also good. Further, the extended welded portion 12E can be welded by a curved line at the edge of the collar cover portion 14C, and the second elongated elastic member 16 of the collar cover portion 14C can be prevented from being pulled.

In addition, the front end portion of the interior body 200 is connected to the inner surface of the belly side exterior sheet 12F in the width direction center portion of the waistline portion 100 by a hot melt adhesive or the like, and the interior body is disposed on the inner surface of the back side exterior sheet 12B in the width direction center portion. The rear end portions of 200 are connected by a hot-melt adhesive or the like, and the abdominal exterior sheet 12F and the back exterior sheet 12B are not continuous on the crotch side and are separated from each other. This separation distance Y can be about 150 to 250 mm.
As can be seen from FIGS. 14 and 15, the upper opening of the waistline portion 100 becomes a waist opening WO through which the wearer's torso passes, and the lower edge of the waistline portion 100 and the interior body 200 on both sides in the width direction of the interior body 200. The portions surrounded by the side edges are leg openings LO through which the legs pass. In a state where each joint 12A is peeled off and developed, an hourglass shape is formed as shown in FIG. The interior body 200 extends from the back side so as to cover the abdominal side through the crotch part, and is a part that receives the excrement and absorbs and holds the liquid, and the waistline part 100 holds the interior body 200. This is the part that supports the wearer.

(Exterior sheet)
The abdominal exterior sheet 12F and the back exterior sheet 12B are formed by laminating the inner sheet 1A and the outer sheet 1B made of a nonwoven fabric or the like as shown in FIGS. Elongated elastic members 15 to 19 such as thread rubber are provided between the sheets 1A and 1B at a predetermined elongation rate. Adhesive is not used for fixing these elongated elastic members 15 to 19 (at least the first, second and third elongated elastic members 15, 16 and 19). The elastic member is sandwiched from both sides in the width direction by the joint portion that joins the outer sheet 1B.
And as shown in the figure, the first, second and third elongated elastic members 15, 16 and 19 are cut at least at the center in the width direction so that the stretching force does not act on the region overlapping the interior body 200. It is configured. By this cutting, the tension of the elongated elastic member is released and fixed between the joints.

When using a nonwoven fabric as sheet | seat 1A, 1B, it is preferable that the basic weight shall be about 10-30 g / m < ² >. The nonwoven fabric is not particularly limited as to what the raw fiber is. For example, synthetic fibers such as olefins such as polyethylene and polypropylene, polyesters and polyamides, recycled fibers such as rayon and cupra, natural fibers such as cotton, and mixed fibers and composite fibers using two or more of them. Etc. can be illustrated. Furthermore, the nonwoven fabric may be manufactured by any processing. Examples of the processing method include known methods such as a spunlace method, a spunbond method, a thermal bond method, a melt blown method, a needle punch method, an air through method, and a point bond method. Further, as the elongated elastic members 15 to 18 and 19, synthetic rubber or natural rubber may be used. Hot melt bonding, heat sealing, or ultrasonic bonding can be used to bond the two sheets 1A and 1B of the respective exterior sheets 12F and 12B and to fix the elongated elastic members 15 to 19 sandwiched therebetween. If the entire surface of the exterior sheets 12F and 12B is firmly fixed, the texture of the sheet is impaired, which is not preferable. By combining these, it is preferable that the elongated elastic members 15 to 19 are firmly bonded and the other portions are not bonded or bonded weakly.
More specifically, the back-side exterior sheet 12B includes a back-side main body portion 13 that occupies the same vertical range as the joint portion 12A, and a back-side extension portion 14 that extends below the back-side main body portion 13. Have. The back extension part 14 has a width direction center part 14 </ b> M that overlaps the interior body 200, and a buttock cover part 14 </ b> C that extends to both sides thereof.

The shape of the dorsal extension 14 can be determined as appropriate, but in the illustrated example, the upper end of the dorsal extension 14 has the same width as the dorsal body 13 and extends below the dorsal body 13. The width is narrowed as the lower side approaches the crotch side. A portion having the same width as that of the back-side main body 13 can be omitted. If comprised in this way, the edge 14e of the width direction outer side of the buttock cover part 14C will come in the shape of a straight line or a curve which approaches the interior body 200 side as it approaches the crotch side, and it is easy to cover a buttock part. It becomes a shape.
Although the dimension of the back side extension part 14 can be determined suitably, as shown in FIG. 12, the width direction length 14x of the collar part cover part 14C (the edge 14e on the width direction outer side of the collar part cover part 14C and the inner body 200) More preferably, the maximum distance in the width direction with respect to the side edge is 80 to 160 mm, and the length 14y (extension length) in the vertical direction of the collar cover portion 14C is 30 to 80 mm. Further, assuming that the area of a quadrangle determined by the widest part in the width direction and the widest part in the vertical direction is S, the area of the back side extension part 14 is 20 to 80% of S, In particular, it is preferable that the content is about 40 to 60% because the outer appearance and wearing feeling of the buttocks are excellent.

The back body 13 can be conceptually divided into an upper end (waist part) W and a lower part U below the upper part in the vertical direction, and the range varies depending on the size of the product. The vertical length of the upper end W can be 15 to 80 mm, and the vertical length of the lower portion U can be 35 to 220 mm.
A plurality of back-side waist elastic members 17 are vertically spaced at the upper end portion (waist portion) W of the back-side main body portion 13 at a predetermined extension rate so as to be continuous over the entire width direction. It is fixed in a stretched state along the direction. Moreover, about the 1 or several arrange | positioned in the area | region adjacent to the lower part U of the back side main-body part 13 among the back side waist part elastic members 17, you may overlap with the interior body 200, You may provide in the width direction both sides except the width direction center part which overlaps with the interior body 200, respectively. The back waist elastic member 17 has a thickness of 155 to 1880 dtex, especially about 470 to 940 dtex (in the case of synthetic rubber. In the case of natural rubber, the cross-sectional area is 0.05 to 1.5 mm ² , particularly 0.1 to 1). the rubber thread .0mm about ^2), 3 to 22 present approximately at intervals of 4 to 12 mm, an extension ratio 150% to 400%, preferably fixed in particular about 220-320%. Further, it is not necessary for all of the back side waist elastic members 17 to have the same thickness and extension rate. For example, the thickness and extension rate of the elastic members may be different between the upper part and the lower part of the back side waist part. The back waist elastic member 17 can be freely determined with respect to the first and second elongated elastic members 15, 16 regardless of the size or the expansion rate.

Further, in the lower portion U of the back-side main body portion 13, except for the width direction central portion that overlaps with the interior body 200, a plurality of portions are provided so as to be continuous over the entire width direction on each of the upper side and both sides in the width direction. The first elongated elastic members 15 are fixed in a state where they are extended along the width direction at a predetermined extension rate with an interval in the vertical direction.
As the first elongated resilient member 15, the thickness 155～1880Dtex, particularly about 470～940Dtex (the case of synthetic rubber. Cross-sectional area in the case of natural rubber 0.05 to 1.5 mm ^2, in particular 0.1 the rubber thread of 1.0mm about ^2), 1 to 15 mm, in particular fixed 5-30 present at intervals of 3 to 8 mm. Here, it is preferable that the elongation ratio in the fixed state after releasing the tension is about 200 to 350%, particularly about 240 to 300%.

Moreover, in the back side extension part 14, except the center part of the width direction which overlaps with the interior body 200, it extends over the whole width direction (at least over the whole collar cover part 14C) to each site | part of the width direction both sides. The plurality of second elongated elastic members 16 are fixed in a state where they are extended along the width direction at a predetermined extension rate with a space in the vertical direction.
As the second elongated resilient member 16, the thickness 155～1880Dtex, particularly about 470～940Dtex (the case of synthetic rubber. Cross-sectional area in the case of natural rubber 0.05 to 1.5 mm ^2, in particular 0.1 About ² to 10 thread rubbers are fixed at intervals of 5 to 40 mm, particularly 5 to 20 mm. Here, the stretch rate in the fixed state after releasing the tension is preferably 150 to 300%, particularly 180 to 260%.

On the other hand, the abdominal exterior sheet 12F is composed of only the abdominal body part basically the same as the back body part 13 of the back exterior sheet 12B (the part occupying the same vertical range as the joint part 12A). It has a rectangular shape extending along the direction, and does not have the back side extension portion 14 like the back side exterior sheet 12B.
That is, among the upper end portion (waist portion) W and the lower portion U of the ventral side exterior sheet (abdominal side main body portion) 12F, the upper end portion W has a plurality of ventral side waist portions so as to be continuous over the entire width direction. The elastic members 18 are fixed in a state where they are stretched along the width direction at a predetermined stretch rate with an interval in the vertical direction. The ventral waist elastic member 18 is preferably as close as possible in number, thickness, stretch rate, spacing, and vertical arrangement with respect to the back waist elastic member 17, but may be different. In the case of fastening, the difference in number is 10 or less, preferably 5 or less, the difference in thickness is 1880 dtex or less, preferably 470 dtex or less, the difference in elongation is 100% or less, preferably 40% or less, and the difference in spacing is 10 mm. Hereinafter, it is preferably 5 mm or less. The stretch rate of the ventral waist elastic member 18 is suitably about 150 to 400%, particularly about 220 to 320%.

Further, in the lower portion U of the abdominal exterior sheet 12F (abdominal side main body portion), except for the widthwise central portion overlapping with the interior body 200, it is continuous over the entire width direction on each of the upper side and both sides in the width direction. As described above, the plurality of third elongated elastic members 19 are fixed in a state of being spaced apart in the vertical direction and stretched along the width direction at a predetermined stretch rate. Although the vertical disposition range of the third elongated elastic member 19 may be a part of the lower portion, it is preferable that the third elongated elastic member 19 is substantially the whole (a range in which a stretching force acts on the whole).
The third elongated elastic member 19 is preferably as close as possible to the first elongated elastic member 15 in terms of number, thickness, stretch rate in a fixed state after releasing the tension, spacing, and vertical arrangement. In this case, the difference in the number is 10 or less, preferably 5 or less, the difference in thickness is 1880 dtex or less, preferably 470 dtex or less, and the difference in the expansion rate in the fixed state after releasing the tension. Is 100% or less, preferably 40% or less, and the difference in spacing is 10 mm or less, preferably 5 mm or less. The stretch rate in the fixed state after releasing the tension of the third elongated elastic member 19 is suitably about 150 to 350%, particularly about 180 to 300%.

The abdominal exterior sheet 12F in the illustrated form is composed of only a portion that occupies the same vertical range as the joint portion 12A, but, similarly to the back side, a ventral main body portion that occupies the same vertical range as the joint portion 12A; In addition, a configuration including an abdominal-side extension portion extending below the abdominal-side main body portion may be employed. Thereby, the leg periphery shape of the abdominal exterior sheet | seat 12F can be made into the shape fitted along a buttock. In this case, the area of the ventral extension part is preferably 10 to 80% of the area of the dorsal extension part, and more preferably 20 to 50%. If the ventral extension is excessively large, the fit is rather impaired, which is not preferable.
And as shown in FIG.14 and FIG.15, among these elongate elastic members 15-19 which form shirring around the waist, the first to third elastic members 15, 16 excluding the waist elastic members 17, 18 are used. , 19 employs the above-described clamping and fixing by the welded portion 3 and is fixed at different expansion rates according to the respective parts. At this time, the expansion ratio before fixing (before cutting) is the same for the first to third elastic members 15, 16, and 19, and the first to third elastic members 15, 16, and 19 are fixed (after release). If the extension ratio in (3) is adjusted by the arrangement pattern of the protrusions on the anvil roll, it is possible to reduce troublesome adjustment work of the extension ratio. Of course, the waist elastic members 17 and 18 can also be fixed at a different expansion rate from the other elastic members by adopting the clamping and fixing by the welded portion 3 described above. In this case, if the stretch rate of the waist elastic members 17, 18 is the same as that of the first to third elastic members 15, 16, 19, it is possible to further reduce the stretch rate adjustment work. Since the tensions 17 and 18 are not released, it is preferable that the initial stretch rate does not exceed 300%. Further, the interval between the elongated elastic members is preferably 7 mm or more, particularly 10 mm or more.

  In the case of using the nonwoven fabric in the range exemplified above as the inner sheet 1A and the outer sheet 1B, as the first to third elongated elastic members 15, 16, and 19, those having the thickness in the range exemplified above are used. In the case of fixing with the expansion rate in the range exemplified above, the interval 3d between the welded portions 3 on both sides of the first elongated elastic member 15 is the width of the elastic member in the non-expanded state (in the case of thread rubber, the thread diameter). The interval 3d between the welded portions 3 on both sides of the second elongated elastic member 16 is set to about 0.46 to 0.52 times, and the width (thread diameter) of the elastic member in the non-stretched state is 0.50 to 0.58. The interval 3d between the welded portions 3 on both sides of the third elongated elastic member 19 is about 0.46 to 0.58 times the width of the elastic member in the non-stretched state (thread diameter in the case of rubber thread). What should I do? FIG. 17 shows an example of the expansion ratio of the elastic members 15 to 19 in each part and an example of the welded portion interval 3d located on both sides of the elastic members 15, 16, and 19. The expansion ratios of the first to third elongated elastic members 15, 16, and 19 shown in the figure are all the expansion ratios in the fixed state after the tension is released.

  On the other hand, when extending over a certain wide range like these elastic members 15, 16, and 19, as shown in FIGS. 14 and 15, the portion fixed by the welded portion 3 is the longitudinal length of the elastic members 15, 16, and 19. An elastic member is provided in a direction (MD direction) intermittently (that is, a welded portion group region 44 composed of a large number of welded portions 3 formed at the above-described arrangement and intervals, and a non-welded portion region 45 having no welded portion. 15 and 16 and 19 are alternately formed in the longitudinal direction (MD direction), and the stretchability is improved and the area of the welded portion 3 is reduced, so that a softer texture and higher air permeability can be obtained. Become. Of course, as shown in FIG. 16, the welded portion group region 44 to be fixed by the welded portion 3 can be provided continuously over the entire longitudinal direction (MD direction) of the elastic members 15, 16, and 19.

  When a large number of elastic members 15, 16, 19 are arranged side by side, if the intermittent arrangement of the welded portion group region 44 is applied, the position in the longitudinal direction (MD direction) of the fixed portion by the welded portion 3 of each elastic member 15, 16, 19 If they are different, the wrinkles formed by the contraction of the elastic member 2 become irregular, and a rough surface with poor appearance is formed. Therefore, when adopting the intermittent arrangement as described above, as shown in FIGS. 14 and 15, it is necessary to align the position of the fixing portion by the welded portion 3 in the longitudinal direction (MD direction) of the elastic members 15, 16, and 19. preferable. Specifically, an elongated welded portion group region 44 that vertically cuts the elastic members 15, 16, and 19 arranged side by side, and a non-welded portion region 45 that vertically cuts the elastic members 15, 16, and 19 arranged side by side. The elastic members 15, 16, 19 are alternately formed in the longitudinal direction (MD direction). As a result, a beautiful shirring of the kites is formed. The width (the distance between the centers of the welded portions 3 located at both ends) W44 of the welded portion group region 44 is preferably about 2 to 10 mm, and more preferably about 3 to 5 mm. It is preferable that the center interval DCT between adjacent welded portion group regions 44 is about 5 to 20 mm. Furthermore, it is more preferable that the relationship of DCT / 2 ≧ W44 is satisfied.

(Interior body)
The interior body 200 can take any shape, but is rectangular in the illustrated form. As shown in FIGS. 9 to 11, the inner body 200 includes a surface sheet 30 on the body side, the liquid-impermeable sheet 11, and an absorbent element 50 interposed therebetween. On the back side of the liquid-impermeable sheet 11, a crotch portion is provided so as to cover the entire back surface of the interior body 200 or to cover the entire portion exposed between the abdominal exterior sheet 12 </ b> F and the back exterior sheet 12 </ b> B. The exterior sheet 12M can also be fixed. In addition, an intermediate sheet (second sheet) 40 can be provided between the top sheet 30 and the absorbent element 50 in order to quickly transfer the liquid that has passed through the top sheet 30 to the absorbent element 50. Furthermore, in order to prevent excrement from leaking on both sides of the absorption part 20, barrier cuffs 60 and 61 that stand on the body side can be provided on both sides of the interior body 200. Although not shown, the constituent members of the interior body 200 can be appropriately fixed to each other by solid, bead or spiral application such as hot melt adhesive. The interior body 200 can also be detachably attached to the exterior sheet 20 using a mechanical fastener or an adhesive material.
In addition, in the width direction both sides of the interior body 200, in particular in the vicinity of the intersection between the width direction both side edges of the interior body 200 and the lower end edge of the ventral exterior sheet 12F and in the vicinity of the intersection of the back side exterior sheet 12B, the interior body 200 is provided. The rigidity (rigidity) of 15 to 50 cN / 50 mm, particularly 20 to 35 cN / 50 mm, is preferable because the overall standing shape of the barrier cuffs 60 and 61 as described later is further stabilized. On the other hand, for other portions, for example, the intermediate portion in the width direction, considering the flexibility, it is preferable to reduce the rigidity to 5 to 35 cN / 50 mm, preferably 10 to 25 cN / 50 mm. In addition, the range which makes rigidity high is the range of 5-30 mm from the width direction both-sides edge of the interior body 200 to the center side in the width direction, and the interior body 200, the abdominal side exterior sheet 12F, and the back side exterior sheet 12B in the front-back direction. It is preferable to be within 50 mm from the intersection point in the front-rear direction (excluding the portion overlapping with the constricted portion 56N of the absorber 56).
Stiffness (rigidity) is measured by the following method in accordance with JIS K 7171 (Plastic-Flexural rigidity test method). For the measurement, a tensilon tester (curvature radius R1 = 5.0 ± 0.1 mm at the tip of the indenter, radius of curvature R2 = 5.0 ± 0.2 mm at the tip of the support plate) was used, and the product 200 of the interior body 200 in the longitudinal direction. Measure the bending stiffness. The test piece is prepared by removing the elastic member that affects the measurement from the inner body 200 and cutting it into a rectangle having a diaper longitudinal direction of 80 mm and a diaper width direction of 50 mm. 50 mm in the unit of the flexural rigidity value is the length of the short side of the test piece, and is the width of the test piece bent with the indenter at the time of the test. On the pair of support plates each having a tip portion having an arcuate cross-section, the interval between the tips (upper ends) of both tip portions being 50 mm, arranged in parallel with each other and the height positions of both tip portions being aligned, The test piece is placed so that its longitudinal direction is directed in a direction perpendicular to each plate, and the tip of the indenter is arranged so as to slightly touch the test piece. A load-deflection curve is obtained by lowering the indenter under conditions of a load cell of 5 kg (range 196 cN) and a speed of 30 mm / min. Let the maximum value of the obtained bending stress be a bending rigidity value (cN / 50 mm). In addition, when the site | part used as a measuring object is smaller than the said sampling dimension, it measures with a small scale test piece, and converts it by proportional calculation based on a dimension ratio.

(Surface sheet)
The surface sheet 30 has a property of transmitting liquid, and examples thereof include a porous or non-porous nonwoven fabric and a porous plastic sheet. Of these, the nonwoven fabric is not particularly limited as to what the raw fiber is. For example, synthetic fibers such as olefins such as polyethylene and polypropylene, polyesters and polyamides, recycled fibers such as rayon and cupra, natural fibers such as cotton, and mixed fibers and composite fibers using two or more of them. Etc. can be illustrated. Furthermore, the nonwoven fabric may be manufactured by any processing. Examples of the processing method include known methods such as a spunlace method, a spunbond method, a thermal bond method, a melt blown method, a needle punch method, an air through method, and a point bond method. For example, if flexibility and drapeability are required, the spunbond method and spunlace method are preferable. If bulkiness and softness are required, the air-through method, point bond method, and thermal bond method are preferable processing methods. .
Further, the top sheet 30 may be composed of one sheet or may be composed of a laminated sheet obtained by bonding two or more sheets. Similarly, the top sheet 30 may be composed of one sheet or two or more sheets in the planar direction.
When the barrier cuffs 60 and 61 are provided, both sides of the top sheet 30 pass between the liquid-impermeable sheet 11 and the barrier cuffs 60 and 61 to the back side of the absorbent element 50 to prevent liquid penetration. Therefore, it is preferable to adhere to the liquid-impermeable sheet 11 and the barrier cuffs 60 and 61 with a hot melt adhesive or the like. Thereby, the effect that the rigidity of the both sides of the interior body 200 is improved is also obtained.

(Intermediate sheet)
An intermediate sheet (also referred to as “second sheet”) 40 having a higher liquid permeation rate than the top sheet 30 can be provided to quickly transfer the liquid that has passed through the top sheet 30 to the absorber. This intermediate sheet 40 not only improves the absorption performance by the absorbent by quickly transferring the liquid to the absorbent body, but also prevents the “reversed” phenomenon of the absorbed liquid from the absorbent body, so that the top sheet 30 is always dried. It can be made into the state which carried out. The intermediate sheet 40 can be omitted.
Examples of the intermediate sheet 40 include the same material as the top sheet 30, spunlace, spunbond, SMS, pulp nonwoven fabric, mixed sheet of pulp and rayon, point bond, or crepe paper. In particular, an air-through nonwoven fabric is preferable because it is bulky. It is preferable to use a core-sheath composite fiber for the air-through nonwoven fabric. In this case, the resin used for the core may be polypropylene (PP), but polyester (PET) having high rigidity is preferable. Basis weight is preferably ^{20~80g / m 2, 25~60g / m} 2 is more preferable. The thickness of the raw fiber of the nonwoven fabric is preferably 2.2 to 10 dtex. In order to make the nonwoven fabric bulky, it is also preferable to use an eccentric fiber, a hollow fiber, or an eccentric and hollow fiber that does not have a core at the center as the mixed fiber of all or part of the raw fiber.
The intermediate sheet 40 in the illustrated form is disposed in the center shorter than the width of the absorber 56, but may be provided over the entire width. The length of the intermediate sheet 40 in the longitudinal direction may be the same as the length of the absorbent body 56 or may be within a short length range centered on the region that receives the liquid. If the intermediate sheet 40 goes from the width direction side part to the back side of the absorbent body 56 and is bonded and fixed by a hot melt adhesive or the like, the rigidity of both side parts of the interior body 200 is improved. A typical material of the intermediate sheet 40 is a nonwoven fabric having excellent liquid permeability.

(Liquid impervious sheet)
The material of the liquid-impermeable sheet 11 is not particularly limited. For example, the liquid-impermeable sheet 11 is substantially made of an olefin resin such as polyethylene or polypropylene, a laminated nonwoven fabric obtained by laminating a nonwoven fabric on a polyethylene sheet, or a waterproof film. Non-woven fabrics that ensure liquid impermeability (in this case, a liquid-impermeable sheet is composed of a waterproof film and a non-woven fabric). Of course, in addition to this, materials having liquid impermeability and moisture permeability, which have been used and used in recent years from the viewpoint of preventing stuffiness, can also be exemplified. As the sheet of the material having liquid impermeability and moisture permeability, for example, an inorganic filler is kneaded in an olefin resin such as polyethylene or polypropylene, and the sheet is formed, and then stretched in a uniaxial or biaxial direction. Examples of the microporous sheet obtained in this way can be given. In addition, non-woven fabric using micro-denier fiber, strengthening leak-proofing by reducing the voids of the fiber by applying heat or pressure, and applying water-absorbing resin or hydrophobic resin or water repellent. A sheet that is liquid-impermeable without using a film can also be used as the liquid-impermeable sheet 11.
The liquid-impermeable sheet 11 is preferably extended around both sides of the absorbent element 50 to both sides of the side surface 30 of the absorbent element 50 in order to improve leakage prevention. Thereby, the effect that the rigidity of the both sides of the interior body 200 is improved is also obtained. The width of this extended portion is suitably about 5 to 20 mm on each of the left and right sides.
In addition, the inner surface or the outer surface of the liquid-impermeable sheet 11 may be designed by printing or coloring. Furthermore, a printed or colored design sheet, which is a separate member from the crotch outer sheet 12M, may be attached to the outside of the liquid-impermeable sheet 11. Further, an excretion indicator 80 whose color changes due to absorption of the liquid component can be provided inside the liquid-impermeable sheet 11.

(Barrier cuffs)
The barrier cuffs 60 and 61 are belt-like members extending along the both sides of the interior body 200 over the entire front-rear direction, blocking urine and soft stool that travel along the top sheet 30 in the lateral direction and prevent side leakage. It is provided to prevent this.
In the present embodiment, as shown in FIGS. 9 and 10, the barrier cuffs 60 and 61 are provided twice on the left and right sides of the interior body 200. In the state in which the diaper is unfolded, as shown in the figure, the inner barrier cuff 61 rises obliquely from the side of the interior body 200 toward the center in the width direction, and the outer barrier cuff 60 is in the width direction of the inner barrier cuff 61. It is provided so as to stand upright from the side of the interior body 200 on the outside, and the base side portion stands obliquely toward the center in the width direction, and the portion on the tip side from the intermediate portion stands obliquely toward the outside in the width direction. To do.

More specifically, the inner barrier cuff 61 folds the belt-like barrier sheet 62 having a length equal to the length in the front-rear direction of the interior body 200 in the width direction and folds it into two. In the meantime, a plurality of elongated elastic members 63 are fixed in a stretched state along the longitudinal direction at intervals in the width direction. The elongated elastic member 63 is not fixed to the barrier sheet 62 at the front and rear end portions, and is fixed so that the barrier cuff extends and contracts forward and backward at the intermediate portion. The barrier sheet 62 is made of a spunbond nonwoven fabric (SS, SSS, etc.), an SMS nonwoven fabric (SMS, SSMMS, etc.), a melt-blown nonwoven fabric with excellent uniformity and concealment, and water-repellent with silicon as necessary. A treated product can be suitably used, and the fiber basis weight is preferably about 10 to 30 g / m ² . As the elongated elastic member 63, thread rubber or the like can be used. When spandex thread rubber is used, the thickness is preferably 420 to 1120 dtex, and more preferably 620 to 940 dtex. The elongation rate at the time of fixation is preferably 150 to 350%, more preferably 200 to 300%. Although not shown, a waterproof film can be interposed between the barrier sheets folded in two.

It is preferable to arrange one or two elongated elastic members 63 at the distal end portion of the inner barrier cuff 61, and it is even more preferable to arrange one or two elongated elastic members 63 at an intermediate portion between the distal end portion and the proximal end portion. When there is the elongated elastic member 63 in the middle part, it becomes easy to hit the skin against the surface in the range from the middle part to the tip part using this as a fulcrum. The arrangement position of the elongated elastic member 63 in the middle portion is preferably in the range of 30 to 70% of the height of the inner barrier cuff 61 (length in the width direction of the protruding portion). In the infant paper diaper, the height of the inner barrier cuff 61 is preferably about 15 to 35 mm. Therefore, the arrangement range of the elongated elastic member 63 is preferably 5 to 25 mm from the distal end to the proximal end, and 12 to 18 mm. More preferred. When the elongated elastic members 63 are provided in parallel at the front end portion and / or the intermediate portion of the inner barrier cuff 61, the arrangement interval 61d is preferably 2 to 10 mm, and more preferably 2 to 6 mm.
The end of the inner barrier cuff 61 opposite to the folded portion in the width direction is an attachment portion (inner attachment portion) 65 fixed to the back surface of the side edge of the interior body 200. The portion is a protruding portion 66 (a portion on the folded portion side and corresponding to the inner protruding portion) protruding from the mounting portion 65, and both ends in the front-rear direction of the protruding portion 66 are hot melt adhesive on the surface of the surface sheet 30. And a front-rear fixing portion 67 by heat sealing, and a middle portion in the front-rear direction is an unfixed free portion (inner free portion), and an elongated elastic member 63 along the front-rear direction is fixed to the free portion in an extended state. Yes.

The outer barrier cuff 60 also has basically the same structure as the inner barrier cuff 61, but its attachment portion (outer attachment portion) 68 is an attachment portion 65 of the inner barrier cuff 61 on the back side of the interior body 200. Further, both ends in the front-rear direction of the projecting portion (outer projecting portion) 69 pass from the mounting portion 68 to the side of the interior body 200, and are fixed to the outer surface of the inner barrier cuff 61 on the center side in the width direction. 61, a base side portion that extends to the surfaces of both end portions in the front-rear direction of the inner projecting portion 66 and is fixed to the surfaces of both end portions in the front-rear direction of the inner projecting portion 66, and is folded back outward in the width direction from the tip of the base side portion. However, the point differs from the front end side portion fixed to the base side portion, the arrangement and number of the elongated elastic members 63, and the like.
However, the inner barrier cuff 61 also has a structure in which the tip of the inner protruding portion is folded outward in the width direction, specifically, not more than 1/2 of the height of the inner barrier cuff 61 (width direction length of the protruding portion), If it is preferably 1/3 or less, a structure in which the tip side portion is folded back in the width direction and fixed to the base portion side portion similarly to the outer barrier cuff 61 may be adopted.

The number of the elongated elastic members 63 provided in the free part (outer free part) of the outer barrier cuff 60 is preferably 2-6, and more preferably 3-5. The arrangement interval 60d is suitably 3 to 10 mm. If comprised in this way, in the range which has arrange | positioned the elongate elastic member 63, it will become easy to hit | skin with respect to skin. The elongated elastic member 63 may be disposed not only at the distal end side but also at the base side. The elongated elastic member 63 disposed on the outer barrier cuff 60 has the same thickness and elongation rate as the inner barrier cuff 61, but the thickness is the same as or larger than that of the inner barrier cuff 61, and the elongation rate is the inner barrier cuff 61. The same or lower is preferable.
In addition, the longitudinal length of the front-rear fixing portion 67 of the protruding portions 66, 69 is preferably formed so that the inner barrier cuff 61 is the same as or shorter than the outer barrier cuff 60, and the elongated elastic cuffs 60, 61 are elongated elastic. The fixed length of the member 63 in the front-rear direction is preferably formed so that the inner barrier cuff 61 is the same as or longer than the outer barrier cuff 60. The boundary between the attachment portion 65 and the protruding portion 66 may be the same position on the outer barrier cuff 60 and the inner barrier cuff 61, but the boundary of the outer barrier cuff 60 is the center in the width direction than the boundary of the inner barrier cuff 61. It is preferable to be spaced apart to the side, and the distance is preferably within 10 mm.

It is preferable to form a linear root fixing part by hot melt adhesive or heat sealing at the edge part on the protruding parts 66, 69 side of the attaching parts 68, 65 of the outer barrier cuff 60 and the inner barrier cuff 61. The other fixing parts can be fixed in an appropriate pattern using a hot melt adhesive or the like. The linear root fixing portion is located in the vicinity of the side portion on the front surface side of the interior body 200 (specifically, the position from 0 to 5 mm in the width direction from the side edge, preferably 0 to 3 mm) or the back surface side. preferable. In this case, since the barrier cuff is folded and fixed to the surface side substantially only at both ends in the front-rear direction, in the crotch part where the restriction to the center in the width direction by the front-rear fixing part 67 does not sufficiently act. The outer barrier cuff 60 and the inner barrier cuff 61 both stand up outward in the width direction, and the pocket formed by the inner barrier cuff 61 becomes wider. When the linear root fixing part is positioned over 5 mm in the width direction from the side edge on the surface side, the barrier cuff rises toward the center in the width direction also in the crotch part, and the pocket formed by the inner barrier cuff 61 is narrow Therefore, it is not preferable. When located on the back side, a position of 0 to 20 mm from the side edge of the interior body 200 is appropriate, but may be located beyond 20 mm.
The fixing target of the attachment portions 68 and 65 of the outer and inner barrier cuffs 60 and 61 can be an appropriate member such as the top sheet 30, the liquid-impermeable sheet 11, and the absorbent element 50 in the interior body 200. The other barrier cuff can be fixed to the interior body 200 via one barrier cuff.

  In the outer and inner barrier cuffs 60 and 61 thus configured, the contraction force of the elongated elastic member 63 acts so as to bring the both ends in the front-rear direction close to each other, but the both ends in the front-rear direction among the protruding parts 66 and 69 do not stand up. 9, while the space between them is an unfixed free part, only the free part stands up to abut against the body side as shown in FIG. 9. In particular, when the attachment portions 68 and 65 are located on the back side of the interior body 200, the outer and inner barrier cuffs 60 and 61 stand up so as to open outward in the width direction at the crotch portion and the vicinity thereof. The barrier cuffs 60, 61 come into contact with the legs around the surface, so that the fit is improved. On the other hand, on both the front and rear sides (abdomen and back) of the crotch part, the inner and rear barrier cuffs 61 are restricted by the front and rear fixing part 67 so that the outer and inner barrier cuffs 60 and 61 do not open outward in the width direction. In addition, since the lower half of the outer barrier cuff 60 is also erected in the same manner, it is possible to surely prevent the abdomen and the back from leaking from both sides of the interior body 200. Further, the front and rear fixing portions 67 of the protruding portion 66 of the inner barrier cuff 61 are not folded back, and the front and rear fixing portions 67 of the protruding portion 68 of the outer barrier cuff 60 are folded outward. , 61 is maintained between the inner and outer free parts, and the outer and inner barrier cuffs 60, 61 are securely raised at a wide interval, and each fits around the leg, providing excellent leakage prevention. It will be.

Although the dimensions of the barrier cuffs 60 and 61 can be determined as appropriate, in the case of an infant paper diaper, for example, as shown in FIG. 13, the standing height of the inner barrier cuff 61 (the length in the width direction of the protruding portion 66 in the unfolded state). ) W5 is 10 to 50 mm, preferably 15 to 35 mm. Standing height of the outer barrier cuff 60 (width direction length of the protruding portion 69 in the unfolded state) W6 is 15 to 60 mm, particularly 20 to 40 mm. Is preferred. Further, the separation distance W4 between the tips in a state where the inner barrier cuff 61 is tilted to the surface of the top sheet 30 is preferably 60 to 170 mm, particularly 70 to 120 mm. Further, it is preferable that the separation distance W3 between the innermost folds when the outer barrier cuff 60 is flatly folded so as to be parallel to the surface of the top sheet 30 is 60 to 190 mm, particularly 70 to 140 mm.
Unlike the illustrated embodiment, only one of the outer and inner barrier cuffs 60 and 61 can be provided.

(Absorption element)
The absorbent element 50 includes an absorbent body 56 and a covering sheet 58 that wraps at least the back and side surfaces of the absorbent body 56. The covering sheet 58 can be omitted.

(Absorber)
The absorber 56 can be formed of an aggregate of fibers. As this fiber assembly, a filament assembly obtained by opening, as necessary, synthetic fiber tows (fiber bundles) such as cellulose acetate as well as short fibers such as cotton-like pulp and synthetic fibers Can also be used. The fiber basis weight can be set to, for example, about 100 to 300 g / m ² when cotton-like pulp or short fibers are stacked, and in the case of a filament aggregate, for example, about 30 to 120 g / m ^2. Can do. The fineness in the case of a synthetic fiber is 1-16 dtex, for example, Preferably it is 1-10 dtex, More preferably, it is 1-5 dtex. In the case of a filament aggregate, the filament may be a non-crimped fiber, but is preferably a crimped fiber. The crimped degree of the crimped fiber can be, for example, 5 to 75, preferably 10 to 50, and more preferably about 15 to 50 per inch. Further, a crimped fiber that is uniformly crimped is often used. It is preferable to disperse and hold superabsorbent polymer particles in the absorber 56.

Although the absorber 56 may be rectangular, as shown in FIGS. 7 and 12, the absorber 56 is located at the front end 56F, the rear end 56B, and between them, and is narrower than the front end 56F and the rear end 56B. The hourglass shape having the constricted portion 56N is preferable because the fit of the absorber 56 itself and the barrier cuffs 60, 61 around the legs is improved. As specific dimensions, the length in the front-rear direction of the absorber front end portion 56F is L1, the length in the front-rear direction at the overlapping portion between the absorber 56 and the ventral exterior sheet 12F is L2, and the length of the absorber rear end portion 56B is The length in the direction is L3, the length in the front-rear direction at the overlapping portion of the absorber 56 and the backside exterior sheet 12B is L4, the minimum width of the constricted portion 56N is W1, the width of the absorber front end portion 56F and the rear of the absorber When the width of the end portion 56B is W2, it is preferable that the end portion 56B is configured to satisfy the following expressions (1) to (4).
70 mm ≦ W1 <W2 ≦ 190 mm (1)
0.5 ≦ W1 / W2 ≦ 0.85 (2)
0 mm ≦ L1-L2 ≦ 70 mm (3)
0mm ≦ L3-L4 ≦ 50mm (4)
If W1 and W2 are too narrow, the standing of the barrier cuffs 60 and 61 becomes unstable, and the amount of absorption becomes insufficient. If it is too wide, the fit feeling deteriorates due to a decrease in fit.

In addition, when the value is within the above numerical range, the absorber 56 does not exist in the vicinity of the attachment portion 65 of the barrier cuffs 60, 61 in the crotch portion. Therefore, the degree of freedom of movement of the barrier cuffs 60, 61 increases, and the barrier cuffs 60, 61 Is easy to open outward in the width direction, and easily touches the skin with the surface, and the followability of the fit surface to the movement of the leg is improved. Since the absorber 56 on the side of the interior body 200 exists in a sufficient range on both the front and rear sides, the standing of the barrier cuffs 60 and 61 is stabilized with this as a base point (fulcrum). A portion extending from the front and rear sides to the crotch portion is a displacement portion in which the barrier cuffs 60 and 61 are opened outward in the width direction from a posture in which the barrier cuffs 60 and 61 are erected on the inner side in the width direction with reference to both side edges in the width direction. The posture change of 60, 61 is supported by the absorber 56 that exists up to the side of the interior body 200, and the overall standing shape of the barrier cuffs 60, 61 is stabilized. If the constricted part is too large outside the above numerical range, the degree of freedom of the barrier cuffs 60 and 61 becomes too high in the crotch part, and there is a possibility that a gap is easily formed around the leg, and both the front and rear sides of the crotch part However, since there is no base point (fulcrum), the standing of the barrier cuffs 60 and 61 may become unstable. Conversely, if the constricted portion becomes too small, the degree of freedom of the barrier cuffs 60 and 61 is lowered, which is not preferable.
Furthermore, the front-rear direction length L7 of the entire constricted portion 56N is preferably 80 mm or more, and particularly preferably 120 to 260 mm. If the length L7 in the front-rear direction of the constricted portion 56N is too short, the degree of freedom of the barrier cuffs 60 and 61 is lowered, and the fit of the absorbent body 56 around the legs is lowered to prevent the movement of the legs, which is too long. And the standing of the barrier cuffs 60 and 61 becomes unstable.

(Superabsorbent polymer particles)
Superabsorbent polymer particles include “powder” in addition to “particles”. As the particle diameter of the superabsorbent polymer particles, those used in this type of absorbent article can be used as they are, and those having a particle size of 1000 μm or less, particularly 150 to 400 μm are desirable. The material of the superabsorbent polymer particles can be used without any particular limitation, but those having a water absorption of 40 g / g or more are suitable. High-absorbent polymer particles include starch-based, cellulose-based, and synthetic polymer-based starch-acrylic acid (salt) graft copolymers, saponified starch-acrylonitrile copolymers, and sodium carboxymethylcellulose crosslinks. Or an acrylic acid (salt) polymer can be used. As the shape of the superabsorbent polymer particles, a commonly used granular material is suitable, but other shapes can also be used.
As the superabsorbent polymer, one integrated with an antibacterial substance can be used. In particular, zeolite particles obtained by substituting some or all of the ion-exchangeable ions in the zeolite with silver ions (hereinafter referred to as antibacterial deodorant zeolite) are contained in the superabsorbent polymer or antibacterial. Antibacterial deodorant superabsorbent polymer particles obtained by adhering deodorant zeolite particles to the surface of superabsorbent polymer particles by static electricity are suitable.
As the superabsorbent polymer particles, those having a water absorption rate of 40 seconds or less are preferably used. When the water absorption speed exceeds 40 seconds, so-called reversion in which the liquid supplied into the absorber 56 returns to the outside of the absorber 56 is likely to occur.
Further, as the superabsorbent polymer particles, those having a gel strength of 1000 Pa or more are preferably used. Thereby, even if it is a case where it is set as the bulky absorber 56, the sticky feeling after liquid absorption can be suppressed effectively.
The basis weight of the superabsorbent polymer particles can be appropriately determined according to the amount of absorption required for the use of the absorber 56. Therefore, although it cannot be said unconditionally, it can be set to 50 to 350 g / m ² . If the amount of polymer is less than 50 g / m ^2, it is difficult to secure the absorption amount. When it exceeds 350 g / m ² , the effect is saturated.
If necessary, the superabsorbent polymer particles can adjust the spraying density or spraying amount in the plane direction of the absorber 56. For example, it is possible to increase the application amount of the liquid excretion site as compared to other sites. When gender differences are taken into account, men can increase the front spray density (amount), while women can increase the center spray density (amount). In addition, a portion where no polymer exists locally (for example, in a spot shape) in the planar direction of the absorber 56 can also be provided.

(Enveloping sheet)
When the covering sheet 58 is used, as the material, tissue paper, particularly crepe paper, non-woven fabric, polylaminated non-woven fabric, a sheet with small holes, or the like can be used. However, it is desirable that the superabsorbent polymer particles be a sheet that does not escape. When a nonwoven fabric is used in place of the crepe paper, a hydrophilic SMMS (spunbond / meltblown / meltblown / spunbond) nonwoven fabric is particularly suitable, and polypropylene, polyethylene / polypropylene, etc. can be used as the material. The basis weight is preferably 5 to 40 g / m ² , particularly 10 to 30 g / m ² .
As shown in FIGS. 9 and 10, the covering sheet 58 may cover only the back surface and side surfaces of the layer in addition to the form for covering the entire absorbent body 56. Although not shown, only the upper and side surfaces of the absorbent body 56 are covered with crepe paper or a nonwoven fabric, and the lower surface is covered with a liquid-impermeable sheet such as polyethylene, and the upper surface of the absorbent body 56 is covered with crepe paper or a nonwoven fabric. For example, the lower surface may be covered with a liquid-impermeable sheet such as polyethylene (each of these materials becomes a component of the covering sheet). If necessary, the absorbent body 56 may be sandwiched between upper and lower two-layer sheets or disposed only on the lower surface, but this is not a desirable form because it is difficult to prevent the movement of the superabsorbent polymer particles.

(Crotch exterior sheet)
A crotch outer sheet 12M exposed on the outer surface of the product is provided on the back surface side of the inner body 200. As the material of the crotch outer sheet 12M, the same material as the abdominal outer sheet 12F and the back outer sheet 12B can be used, but a material containing a higher-strength material or a deodorant, etc. A material different from the exterior sheet 12F and the back-side exterior sheet 12B may be used. Specifically, various nonwoven fabrics such as spunbond nonwoven fabric, melt blown nonwoven fabric, point bond nonwoven fabric, air-through nonwoven fabric, air point nonwoven fabric, spunlace nonwoven fabric, SMS nonwoven fabric, and the like made of fibers of PP, PP / PE, PP / PET, or the like, or What added the deodorizer etc. to this can be used.
A high body pressure is applied to the crotch outer sheet 12M when sitting. Therefore, a material having a high friction fastness (not fuzzy) is preferable.
The crotch outer sheet 12M may be a sheet provided with design elements by printing or coloring. When used in combination with the above-described design sheet, it is preferable to dispose the designs so that they do not overlap.
It is preferable to use a stretchable nonwoven fabric as the crotch outer sheet 12M and to extend and paste it in the longitudinal direction of the inner body 200 because the fit of the crotch part is improved.
When the crotch outer sheet 12M wraps around from the side in the width direction to the side of the body and is bonded and fixed to the outer surface of the barrier sheet 62 with a hot melt adhesive or the like, the rigidity of both sides of the inner body 200 is improved. In such a form, it is preferable to use a sheet having high rigidity (roughness) as the crotch outer sheet 12M. Specifically, a sheet having a bending resistance measured by the Clark method (JISL1096 C method) and a sum of the MD direction and the CD direction of the sheet of 100 mm or more, preferably 150 mm or more may be used.
In the illustrated example, the crotch outer sheet 12M is sandwiched between the inner body 200 and the abdominal and dorsal exterior sheets 12F and 12B where the ventral and dorsal exterior sheets 12F and 12B overlap the interior body 200. However, it is also possible to affix them to the outside of the ventral and back side exterior sheets 12F and 12B. The crotch outer sheet 12M is affixed to the back surface of the inner body 200 and the inner or outer surfaces of the abdominal and back-side outer sheets 12F and 12B with a hot melt adhesive or the like.

It is a schematic diagram for demonstrating an expansion-contraction part formation apparatus. It is the width direction sectional view of 1st Embodiment which shows the state where the continuous sheet was pinched | interposed into the horn and the anvil roll, and its cross-sectional view. It is the cross-sectional view of the width direction of 1st Embodiment of the continuous sheet of the state which applied the tensile force to the elastic member, and its cross-sectional view. It is the cross-sectional view of the width direction of 1st Embodiment of the continuous sheet of the state which does not apply tensile force to an elastic member, and its cross-sectional view. It is the width direction sectional drawing of 2nd Embodiment which shows the state by which the continuous sheet was pinched | interposed into the horn and the anvil roll, and its cross section. It is a perspective view which shows the cutting process of an elastic member. It is a top view in the state where the diaper was developed showing the inside of a pants type disposable diaper. It is a top view in the state where the diaper was developed showing the outer surface of a pants type disposable diaper. It is III-III sectional drawing of FIG. It is IV-IV sectional drawing of FIG. It is VV sectional drawing of FIG. It is a top view in the state where a diaper was developed showing only a principal part of a pants type disposable diaper with a size. It is sectional drawing which shows only the principal part of an underpants type disposable diaper with a dimension. It is a front view of a product state. It is a rear view of a product state. It is a front view of the product state of another pants-type disposable diaper. It is the schematic which shows the example of a specification of an elastic member.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Sheet, 2 ... Elastic member, 3 ... Welding part, 4 ... Continuous sheet, 5 ... Ultrasonic vibration source, 6 ... Horn, 7 ... Anvil roll, 7A, 7C protrusion.

Claims (5)

A plurality of elongated elastic members are stretched in the longitudinal direction and are arranged in parallel between the inner sheet and the outer sheet, and the inner sheet and the outer sheet are joined in the vicinity of both ends in the width direction of the elastic members. After that, the tension applied to the elastic member is released to expand the diameter of the elastic member by contraction, and the elastic member is connected between the joint near the one end in the width direction and the joint near the other end in the width direction. An elastic part forming method for fixing with an elastic member in between,
The distance between the joint near one end in the width direction of some elastic members and the joint near the other end in the width direction, and between the joint near one end in the width direction of the other elastic member and the other end in the width direction. Make the gap with the joint different,
A stretchable part forming method characterized by the above.   The plurality of elastic members have the same stretch rate when sandwiched between the inner sheet and the outer sheet, and have the elastic member expanded in diameter by contraction. The stretchable part forming method according to claim 1, wherein the stretch rate of some of the elastic members is different from the stretch rate of the other elastic members.   The interval between the joint portion in the vicinity of one end portion in the width direction of each elastic member and the joint portion in the vicinity of the other end portion in the width direction is 10 to 90% of the width of the elastic member in the non-stretched state. 3. The stretchable part forming method according to 2.   The stretchable part formation according to any one of claims 1 to 3, wherein the inner sheet and the outer sheet are joined by intermittently welding the inner sheet and the outer sheet along the elastic member. Method. An exterior sheet having at least a waistline portion and having a portion in which the inner layer and the outer layer are bonded to the waistline portion;
An interior body provided on the body side of the exterior sheet for absorbing and holding an object;
Between the inner layer and the outer layer in the waist portion, a plurality of elongated elastic members are provided in parallel in a state of extending along the waist direction,
The inner layer and the outer layer are bonded to each other on both sides in the width direction of each elastic member without using each elastic member, and a bonded portion is formed.
Each of the elastic members is a disposable diaper that is sandwiched and fixed between a joint portion on one side in the width direction and a joint portion on the other side in the width direction,
The distance between the joint portion on the one side in the width direction and the joint portion on the other side in the width direction of some of the elastic members, and the joint portion on the one side in the width direction and the joint portion on the other side in the width direction of the other elastic members. The interval is different,
A disposable diaper characterized by that.

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