JP6255266B2 - Pants-type absorbent article - Google Patents

Description

  The present invention relates to a pants-type absorbent article that absorbs excreted fluid such as urine.

  Conventionally, a pants-type disposable diaper has been used as an absorbent article that absorbs excreted fluid such as urine. This diaper has an abdominal side portion disposed on the stomach side of the wearer when worn, a back side portion disposed on the back side of the wearer, and a crotch portion disposed between the crotch of the wearer. And, in such a state that the diaper is folded in two at the crotch and the abdomen and the dorsal part are overlapped, the abdomen and the dorsal part are joined at each end in the lateral direction, It is provided to the user in the form of a pants-type diaper in which a waist opening and a pair of leg openings are formed.

  Patent Document 1 discloses an example of this pant-type diaper. FIG. 1A is a schematic enlarged view of a lateral end portion of the diaper 1 ′, and FIG. 1B is a schematic view taken along line BB in FIG. 1A. As shown in FIG. 1A, in the diaper 1 ', each end in the lateral direction of the abdominal side part 11a and the back side part 11b is accompanied with the joining of the abdominal side part 11a and the back side part 11b. Each part has a junction j. The joint j extends from the waistline opening 1HB to the leghole opening 1HL. Further, when the excreted diaper 1 ′ is removed from the wearer, the diaper 1 ′ is removed from the wearer by peeling off the abdomen portion 11a and the dorsal portion 11b at the joint j ′. .

  Here, in Patent Document 1, as an example of such a joint j ′, welded portions jm ′, jm ′... Which are horizontally long and long in the horizontal direction extend from the waistline opening 1HB to the leghole opening 1HL. A plurality of joint portions j ′ are disclosed, and in the vicinity of the waistline opening 1HB, the lateral length of the welded portion jm ′ is shortened.

JP2013-119008A

  And according to this diaper 1 ', about the welding part jm' near the trunk periphery opening part 1HB, the length of the horizontal direction is shortened. Therefore, it is considered that the bonding strength (N) at this position is small. Therefore, the abdomen portion 11a and the dorsal portion 11b are pulled relatively easily starting from the welded portion jm ′ located in the waistline opening 1HB. It can be peeled off.

However, in some cases, it may be preferable that the abdomen side portion 11a and the back side portion 11b can be easily peeled off from the welded portion jm ′ located in the leg opening 1HL.
For example, if it is difficult to peel off the ventral portion 11a and the dorsal portion 11b at the welded portion jm ′, the vicinity of the welded portion jm ′ in the diaper 1 ′ will be broken. Is easier to break when the basis weight (g / m ² ) in the vicinity is smaller. And there are two candidates for the vicinity portion to be broken, a portion 11HB forming the waist opening 1HB and a portion 11HL forming the leg opening 1HL. Here, as shown in FIG. 1B, the waist opening The portion 11HB forming 1HB generally has a larger basis weight (g / m ² ) than the portion 11HL forming the leg opening 1HL due to folding of the sheet. For this reason, the portion 11HL forming the leg opening 1HL is often easier to break. In such a case, the ventral portion 11a and the back portion 11b are separated from each other with the leg opening 1HL as a starting point. It is considered convenient if it can be easily peeled off.

  The present invention has been made in view of the above-described conventional problems, and an object thereof is to make it possible to easily peel off the abdomen and the dorsal part starting from the leg opening. is there.

The main invention for achieving the above object is:
An absorbent article having an abdominal side portion arranged on the abdomen side of the wearer at the time of wearing, a back side portion arranged on the back side of the wearer, and a crotch portion arranged between the crotch of the wearer. In the state where the abdomen and the dorsal part are overlapped by folding in two at the crotch part, the abdomen and the dorsal part are joined at respective lateral ends. A pants-type absorbent article in which a waist opening and a pair of leg openings are formed,
Each joint formed at each end in the lateral direction to join the abdomen and the dorsal side is respectively from the waistline opening to the leghole opening. Extended,
Of at least one of the joints, the joint strength of the first part closest to the leg opening is between the first part and the waist opening of the joint. Smaller than the bonding strength of the predetermined part located ,
The joint has a second portion adjacent to the waist opening side of the first portion,
The bonding strength of the second portion is a size between the bonding strength of the first portion and the bonding strength of the predetermined portion,
Of the joints, the joint strength of the third part closest to the waistline opening is smaller than the joint strength of the predetermined part,
The joint portion includes a fourth portion adjacent to the leg opening portion side of the third portion,
The pants-type absorbent article is characterized in that the bonding strength of the fourth portion is a size between the bonding strength of the third portion and the bonding strength of the predetermined portion .
Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

  According to the present invention, it is possible to easily peel off the abdomen and the dorsal side from the leg opening.

FIG. 1A is a schematic enlarged view of a lateral end portion of a diaper 1 ′ of a reference example, and FIG. 1B is a schematic view taken along line BB in FIG. 1A. It is a schematic perspective view of the underpants type disposable diaper 1 as an example of the underpants type absorbent article of this embodiment. 3A is a schematic plan view of the unfolded diaper 1 as viewed from the skin side, and FIG. 3B is a schematic view taken along the line BB in FIG. 3A. It is a schematic perspective view which decomposes | disassembles and shows the diaper 1 of an unfolding state. It is the schematic plan view which looked at the exterior sheet | seat 11 of the unfolded state from the non-skin side. 6A is a schematic enlarged view of the joint j, and FIG. 6B is a schematic view taken along the line BB in FIG. 6A. It is explanatory drawing of the sample S for a measurement provided in order to measure the vertical distribution of the joint strength (N) in the junction part j. It is a schematic enlarged view of the junction part j for demonstrating other embodiment. It is the schematic plan view which looked at the 3 piece type diaper of the unfolding state from the skin side.

At least the following matters will become apparent from the description of the present specification and the accompanying drawings.
An absorbent article having an abdominal side portion arranged on the abdomen side of the wearer at the time of wearing, a back side portion arranged on the back side of the wearer, and a crotch portion arranged between the crotch of the wearer. In the state where the abdomen and the dorsal part are overlapped by folding in two at the crotch part, the abdomen and the dorsal part are joined at respective lateral ends. A pants-type absorbent article in which a waist opening and a pair of leg openings are formed,
Each joint formed at each end in the lateral direction to join the abdomen and the dorsal side is respectively from the waistline opening to the leghole opening. Extended,
Of at least one of the joints, the joint strength of the first part closest to the leg opening is between the first part and the waist opening of the joint. A pants-type absorbent article characterized by being smaller than the bonding strength of a predetermined portion located.

  According to such a pants-type absorbent article, the bonding strength of the first portion closest to the leg opening is made smaller than the bonding strength of the predetermined portion. Therefore, while maintaining the joint strength of the joint portion as a whole to withstand the wearing of the absorbent article, the first portion located on the leg opening side of the joint portion as a starting point, The back side portion can be easily peeled off. That is, the abdominal side and the back side can be easily peeled off from the leg opening.

Such a pants-type absorbent article,
The joint has a second portion adjacent to the waist opening side of the first portion,
The bonding strength of the second portion is preferably a magnitude between the bonding strength of the first portion and the bonding strength of the predetermined portion.

  According to such an underpants-type absorbent article, the bonding strength of the second portion is set to a magnitude between the bonding strength of the first portion and the bonding strength of the predetermined portion. Therefore, the joint strength of the part located in the vicinity of the leg hole opening in the joint part decreases as the leg hole opening is approached. Therefore, it is possible to smoothly peel the abdomen and the dorsal side from the first portion located on the leg opening side in the joint.

Such a pants-type absorbent article,
It is desirable that the bonding strength of the third portion closest to the waist opening in the bonding portion is smaller than the bonding strength of the predetermined portion.

  According to such a pants-type absorbent article, the bonding strength of the third portion closest to the waistline opening is made smaller than the bonding strength of the predetermined portion. Therefore, if it is difficult to peel off the abdominal part and the dorsal part starting from the first part closest to the leg opening in the joint based on some cause, It is possible to switch to the peeling starting from the nearest third part, and thereby the absorbent article can be quickly removed.

Such a pants-type absorbent article,
The joint portion includes a fourth portion adjacent to the leg opening portion side of the third portion,
It is desirable that the bonding strength of the fourth portion is a size between the bonding strength of the third portion and the bonding strength of the predetermined portion.

  According to such a pants-type absorbent article, the bonding strength of the fourth portion is set to a magnitude between the bonding strength of the third portion and the bonding strength of the predetermined portion. For this reason, the bonding strength of the portion located in the vicinity of the waistline opening portion of the joint portion decreases as it approaches the waistline opening portion. Therefore, the abdominal side and the back side can be smoothly peeled off starting from the third portion located on the waist opening side of the joint.

Such a pants-type absorbent article,
The bonding strength of the first portion is preferably smaller than the bonding strength of the third portion.

  According to such a pants-type absorbent article, the bonding strength of the first part closest to the leg opening is smaller than the bonding strength of the third part closest to the waist opening. Therefore, the ventral part and the dorsal part can be quickly peeled off from the leg opening.

Such a pants-type absorbent article,
The basis weight (g / m ² ) of the part that forms the leg opening in the ventral part and the dorsal part is the basis weight (g / m ² ) of the part that forms the waist opening in the ventral part and the dorsal part ( It is desirable to be smaller than g / m ² ).

According to such a pants-type absorbent article, the absorbent article can be easily detached from the abdomen and the dorsal side starting from the leg opening, and the absorbent article can be quickly removed.
That is, if it is difficult to peel off the abdomen and the dorsal part starting from the first part closest to the leg opening among the joints based on some cause, Based on the small basis weight (g / m ² ) of the portion that forms the leg opening in the side portion and the back side portion, the portion or the vicinity thereof can be broken relatively easily. And thereby, an absorptive article can be quickly divided into a stomach side part and a back side part from a leg circumference opening.

Such a pants-type absorbent article,
It is desirable that both of the joints have the first part and the predetermined part, respectively.

  According to such a pants-type absorbent article, each of the joints formed at the respective lateral ends is located on the leg opening side of the joint. It is possible to easily peel off the abdominal part and the dorsal part starting from the first part. Therefore, even if the worker who peels off selects either of the two leg opening parts, the worker can easily peel off the ventral part and the dorsal part, Thereby, the said operator can take off an absorbent article rapidly.

=== This Embodiment ===
FIG. 2 is a schematic perspective view of a pant-type disposable diaper 1 as an example of the pant-type absorbent article of the present embodiment. 3A is a schematic plan view of the unfolded diaper 1 as viewed from the skin side, and FIG. 3B is a schematic view taken along the line BB in FIG. 3A. FIG. 4 is an exploded schematic perspective view showing the diaper 1 in the unfolded state. FIG. 5 is a schematic plan view of the unfolded exterior sheet 11 as seen from the non-skin side.

  In the following description, when the diaper 1 is attached to the wearer, the side that should be located on the skin side of the wearer is simply referred to as “skin side”, and on the other hand, on the non-skin side of the wearer. The side to be positioned is simply referred to as the “non-skin side”.

  As shown to FIG. 3A, this diaper 1 is the diaper 1 of a 2 piece type, for example. That is, the diaper 1 has, as a first part, an absorbent main body 3 having a substantially rectangular shape in plan view that absorbs excretory fluid such as urine, and is provided to cover the non-skin side surface of the absorbent main body 3. The exterior sheet 11 having a substantially hourglass shape in plan view that forms the exterior of the diaper 1 is provided as the second component.

  As shown in FIGS. 3A, 3B, and 4, the absorbent main body 3 has an absorbent core 3c that absorbs excretory fluid. The absorbent core 3c is formed by molding liquid absorbent fibers such as pulp fibers and liquid absorbent granular materials such as superabsorbent polymers into a substantially hourglass shape in plan view as an example of a predetermined shape. In addition, this absorptive core 3c may be coat | covered with liquid-permeable coating sheets, such as tissue paper, as needed.

  The skin side surface of the absorbent core 3c is provided with a liquid-permeable top sheet 4 such as a nonwoven fabric so as to cover the entire surface, and similarly, on the non-skin side surface of the absorbent core 3c. Is provided with a liquid-impermeable leak-proof sheet 5 such as a film so as to cover the entire surface. Here, in this example, both the sheets 4 and 5 are formed in a substantially rectangular shape in plan view, and both the sheets 4 and 5 are outside the outer contour of the absorbent core 3c over the entire circumference. Is jumping out. And the part which protruded in the top sheet 4 and the part which protruded in the leak-proof sheet 5 are mutually joined by adhesion | attachment, welding, etc. As a result, the absorptive main body 3 of planar view substantially rectangular shape is formed. .

  Although not shown, thread rubber as an elastic member may be provided along the longitudinal direction of the main body 3 at both ends of the absorbent main body 3 in the width direction. Such a rubber thread imparts elasticity to the vicinity of the leg opening 1HL in the absorbent main body 3 and the exterior sheet 11. Accordingly, the rubber thread is inserted between the top sheet 4 and the leak-proof sheet 5 and is stretched from a natural length to a predetermined magnification such as 2 to 4 times by an adhesive such as a hot melt adhesive. It is fixed to both sheets 4 and 5.

  In some cases, a leak-proof wall (not shown) may be provided in the absorbent main body 3 for the purpose of preventing side leakage of urine. Such a leak-proof wall portion is also called a three-dimensional gather, and is provided so as to stand at both end portions such as the skin side surface of the absorbent main body 3 using a flexible sheet such as a nonwoven fabric as a material. However, this leak-proof wall part is a well-known structure. Therefore, further explanation is omitted.

  The exterior sheet 11 is a flexible sheet having a substantially hourglass shape in plan view in the unfolded state of FIG. 5, and the sheet 11 has a thickness direction, a longitudinal direction, and a width direction as three directions orthogonal to each other. ing. Moreover, the said exterior sheet | seat 11 is divided into three parts 11a, 11b, and 11c regarding a longitudinal direction. That is, the exterior sheet 11 is provided on the abdomen side portion 11a disposed on the wearer's belly side, the back side portion 11b disposed on the wearer's back side, and the crotch portion 11c disposed on the wearer's crotch. It is divided. Needless to say, the crotch part 11c is located between the abdominal part 11a and the dorsal part 11b, so that the crotch part 11c has a shape that is constricted in the width direction in a substantially hourglass shape in plan view. This is a portion 11c.

As shown in FIG. 4, the exterior sheet 11 has a single sheet 12 as a main body, or a laminated sheet obtained by laminating and integrating a plurality of sheets as a main body. The main body. In addition, the material of the sheet | seat 12 used as this main body uses the nonwoven fabric containing a thermoplastic resin fiber, a thermoplastic resin film, etc., In this example, the SMS nonwoven fabric (spun bond) of 15 (g / m < ² >) is used. / Melt blown / spunbond nonwoven fabric) is used, but not limited to this.

Moreover, as shown in FIG.4 and FIG.5, in this example, another sheet | seat 13a, 13b is respectively provided in the non-skin side of the said sheet | seat 12 with respect to the abdominal side part 12a and the back | dorsal side part 12b in the same sheet | seat 12. Are joined by adhesion or welding, but another sheet is not joined to the crotch part 12c. However, the present invention is not limited to this, and another sheet may be joined to the crotch part 12c, and further, another sheet of the crotch part 12c is connected to another sheet 13a and a dorsal part 12b of the ventral part 12a. The other sheet 13b may be integrated. In addition, as the material of the other sheets 13a and 13b, a nonwoven fabric including a thermoplastic resin fiber, a thermoplastic resin film, or the like is used. In this example, a basis weight of 17 (g / m ² ) including a thermoplastic resin fiber is used. An amount of spunbond nonwoven is used, but not limited to this.

  Hereinafter, the sheet 12 serving as the main body of the exterior sheet 11 is referred to as a “main body sheet 12”, and the other sheet 13 a bonded to the ventral side portion 12 a of the main body sheet 12 is referred to as a “belly side portion. The outer sheet 13a ”is referred to as the other sheet 13b joined to the back side portion 12b of the main body sheet 12 and is referred to as a“ back side outer sheet 13b ”.

  Here, as shown in FIGS. 4 and 5, as an example of an elastic member, between the main body sheet 12 and the abdomen outer surface sheet 13a and between the main body sheet 12 and the back side outer surface sheet 13b, respectively. Thread rubbers 15, 15... Are inserted. The thread rubbers 15, 15... Impart stretchability in the width direction to the abdomen side portion 11a and the back side portion 11b of the exterior sheet 11. Therefore, the rubber thread 15, 15... Is arranged along the width direction in a state of being stretched up to a predetermined magnification such as 2 to 4 times from the natural length, and each of the expanded state by an adhesive such as a hot melt adhesive. It is fixed to the sheets 12, 13a, 13b. A plurality of the thread rubbers 15, 15... Are arranged side by side in the longitudinal direction of the main body sheet 12 with a space between each other, whereby the longitudinal side portion 11a and the back side portion 11b have the longitudinal length. Stretchability is given over a wide range of directions.

  Further, as shown in FIG. 4, the abdomen outer sheet 13a and the dorsal outer sheet 13b are provided so as to protrude outward from the longitudinal edges 12eLa and 12eLb of the main body sheet 12, respectively. The portions 13ap and 13bp that protrude outward from the main body sheet 12 in the respective sheets 13a and 13b are folded back inward in the longitudinal direction. As a result, as shown in FIG. 13 ap and 13 bp are superimposed on the skin side surface of the main body sheet 12. As a result, the end edges 11HBa and 11HBb serving as the waistline opening 1HB are formed by the folded portion 13ak of the abdomen-side outer sheet 13a and the folded portion 13bk of the back-side outer sheet 13b. The edge portions 12eLa and 12eLb of the main body sheet 12 are covered with the portions 13ak and 13bk. Therefore, the skin of the wearer is prevented from being damaged by the edge portions 12eLa and 12eLb of the main body sheet 12. In this example, as apparent with reference to FIGS. 3A and 3B, the protruding portions 13 ap and 13 bp superimposed on the skin side surface of the main body sheet 12 are further in the longitudinal direction of the absorbent main body 3. Each end 3ea, 3eb is also covered from the skin side, but is not limited to this. That is, it may not be covered.

  As shown in FIGS. 3A and 4, at the center position in the width direction of the skin side surface of the exterior sheet 11, that is, the skin side surface of the main body sheet 12, the above-described absorbent main body 3 is in a state in which the longitudinal directions thereof are aligned. It is fixed. In addition, the length in the longitudinal direction and the length in the width direction of the absorbent main body 3 are set such that the absorbent main body 3 can be generally accommodated inside the exterior sheet 11.

  And the exterior sheet | seat 11 to which the absorptive main body 3 was fixed like FIG. 3A is folded in two by the crotch part 11c, and the abdominal side part 11a and the back side part 11b are piled up. In this overlapped state, the abdomen side portion 11a and the back side portion 11b are joined at each end in the width direction, so that the waistline opening 1HB and the pair of legs around as shown in FIG. It is made into the form of the underpants type diaper 1 in which the opening parts 1HL and 1HL were formed.

  In addition, below, it defines as follows about the direction of the three-dimensional shape of the diaper 1 made into the underpants like FIG. First, a direction parallel to the width direction of the exterior sheet 11 is referred to as a “lateral direction”. A direction parallel to the longitudinal direction of the exterior sheet 11 is referred to as a “longitudinal direction”. The horizontal direction and the vertical direction are orthogonal to each other. A direction perpendicular to both the horizontal direction and the vertical direction is referred to as a “front-rear direction”. The front in the front-rear direction is the abdomen side that is the front side of the wearer, and the rear side in the front-rear direction is the back side that is the rear side of the wearer. In addition, when the diaper 1 is worn, the vertical direction is the vertical direction, so the vertical direction is also referred to as the “vertical direction”. Incidentally, in the vertical direction, the leg opening 1HL is located below the waist opening 1HB. Further, the lateral direction is also referred to as “left-right direction”.

  The above-described joining is performed by an ultrasonic welding process, a heat seal process, or the like. In this example, the bonding is performed by an ultrasonic welding process. And in connection with this joining, the junction part j is each formed along the vertical direction in each edge part of the abdominal side part 11a of the exterior sheet | seat 11, and the back side part of the exterior sheet | seat 11 similarly. A junction j is also formed along the vertical direction at each end in the horizontal direction of 11b (FIG. 2). It should be noted that the joint j of the abdomen 11a and the joint j of the back 11b are integrated and are the same so-called so-called front and back positional relationships at the end. Therefore, no distinction is made in the following description.

  6A is a schematic enlarged view of the joint j, and FIG. 6B is a schematic view taken along the line BB in FIG. 6A. As described above, the joint j extends from the waistline opening 1HB toward the leghole opening 1HL in the longitudinal direction. Specifically, the joint j has a plurality of welded portions jm, jm... Formed in a longitudinal direction indented in the front-rear direction (direction passing through the paper surface in FIG. 6A), and the plurality of welded portions jm, jm. Are formed by a welding pattern having a predetermined regularity. For example, in this example, each welded portion jm is formed in a substantially rectangular shape that is long in the lateral direction with a space between each welded portion jm adjacent in the vertical direction.

And in this embodiment, the welding part jm located in the lowest part of the vertical direction among the junction parts j, ie, the welding part jm (corresponding to the first part) closest to the leg opening 1HL among the junction parts j. In the following description, the bonding strength (N) of the welded portion jmb) of each of a plurality of welded portions jm (corresponding to a predetermined portion, hereinafter also referred to as a welded portion jmc) located in the central portion in the vertical direction. It is smaller than the bonding strength (N). Further, the “joining strength” referred to here is a magnitude (N) of an external force required to peel off the abdominal portion 11a and the dorsal portion 11b along the vertical direction.
Therefore, according to the diaper 1, the joint strength of the joint portion j as a whole can withstand the wearing of the diaper 1 based on the large joint strength of each of the plurality of welded portions jmc, jmc. While maintaining the size, the joint between the ventral portion 11a and the dorsal portion 11b can be released with a relatively small external force starting from the weld portion jmb positioned at the lowest position in the vertical direction. As a result, the abdomen portion 11a and the dorsal portion 11b can be quickly and easily peeled from the leg opening 1HL side.

  Further, in this example, as shown in FIG. 6A, the welded portion jmb positioned at the lowest position in the vertical direction for any of the joint portions j and j (FIG. 2) formed at the left and right end portions in the horizontal direction. Are made smaller than the bonding strength of each of the plurality of welded portions jmc, jmc. Therefore, regardless of which opening 1HL of the left and right leg opening 1HL, 1HL in FIG. 2 is selected by a diaper changing operator, the abdomen 11a and the back 11b are easily pulled. The worker can remove the diaper 1 promptly. However, the present invention is not limited to this. That is, only the joint portion j at one of the left and right end portions in the lateral direction may have the above specifications.

  In addition, the joining strength (N) of the welded portion jmb is selected from, for example, a value of 5% to 70% of the joined strength (N) of the welded portion jmc, and preferably 10% to 50% of the joined strength (N). More preferably, it is selected from a value of 20% to 40% of the joint strength (N).

  In addition, the number of the plurality of welded portions jmc positioned at the central portion in the vertical direction in which the lowest welded portion jmb and the bonding strength (N) should be compared may be, for example, 2 to 20 pieces, Or 5-15 pieces may be sufficient. Furthermore, in the above description, the bonding strength (N) of the lowermost welded portion jmb is made smaller than the bonding strength (N) of each of the welded portions jmc, jmc. However, it is not limited to this. For example, in some cases, among the welded portions jm, jm,... Of the welded portion j, the welded portions at the lowermost portion of the welded portions jm, jm. The joint strength (N) of jmb may be reduced.

  The vertical distribution of the bonding strength (N) at the bonded portion j can be measured, for example, as follows. First, while taking care not to cut the joint portion j, the lateral end of the exterior sheet 11 is separated from the diaper 1 into a strip shape that is long in the vertical direction, thereby forming a strip shape that is long in the vertical direction as shown in FIG. A measurement sample S is prepared. And when the part Njm in which the welding part jm is not formed exists in the longitudinal direction lower end part of the measurement sample S, the part Njm in which the welding part jm is not formed is taken as the ventral part 11a and the back side. These are used as a pair of knobs divided into parts 11b. In other words, one of the pair of knobs is chucked to one head of a tensile tester (not shown) (for example, AUTOGRAPH (model AG-1kNI) manufactured by Shimadzu Corporation), and the other knob is the same. Chuck to the other head of the testing machine. Here, one head is a fixed head fixed to the tester so as not to move, and the other head is a moving head that is provided coaxially below the fixed head and is movable in the vertical direction. Then, while measuring the tensile load value (N) acting on the head by the load cell provided on the fixed head, the moving head is separated downward from the fixed head at a constant moving speed value of 300 (mm / min). Go. As a result, the abdomen portion 11a and the dorsal portion 11b of the measurement sample S are sequentially peeled off, that is, the position at which the measurement sample S is peeled is the vertical direction from the lower end portion to the upper end portion of the measurement sample S However, when the position finally reaches the upper end, the measurement sample S is completely separated by the ventral part 11a and the dorsal part 11b, and that is the case. If so, the measurement ends.

  Incidentally, in the case where the welded portion jm is formed up to the end of the lower end portion in the vertical direction of the measurement sample S, it is difficult to form a pair of knobs on the lower end portion. A pair of knobs may be formed on the upper end portion while sacrificing some welded portions jm, jm at the upper end portion in the vertical direction of S, and this may be peeled off from the upper end portion to the lower end portion.

  By the way, desirably, the welded portion jm located at the uppermost position in the vertical direction among the joined portions j in FIG. 6A, that is, the welded portion jm closest to the waistline opening 1HB (corresponding to the third portion). In the following description, the joint strength (N) of the welded portion jmt) is also made smaller than the joint strength (N) of each of the welded portions jmc, jmc. good.

  And if it does in this way, when peeling from the leg periphery opening part 1HL is difficult for some reasons, it can switch to peeling from the trunk periphery opening part 1HB immediately, and, thereby, the diaper 1 Can be removed promptly.

  In this case, the magnitude relationship between the bonding strength (N) of the welded portion jmb closest to the leg opening 1HL and the bonding strength (N) of the welded portion jmt closest to the trunk opening 1HB is mutually related. The same value may be used, or the former may be made smaller. Incidentally, if the former is made smaller, it can be easily peeled off from the leg opening 1HL.

By the way, in the example of FIG. 6A, the area (m ² ) of the welding portion jmb (jmt) to be reduced whose bonding strength (N) should be reduced is smaller than the area (m ² ) of the welding portion jmc that is not the reduction target. In addition, the bonding force (N / m ² ) per unit area of the welding portion jmb (jmt) to be reduced is determined as the bonding force (N / m ² ) per unit area of the welding portion jmc not to be reduced. The joint strength (N) of the welded portion jmb (jmt) to be reduced is made smaller than the joint strength (N) of the welded portion jmc not to be reduced. Not exclusively. That is, as long as the bonding strength (N) of the welding portion jmb (jmt) to be reduced is smaller than the bonding strength (N) of the welding portion jmc that is not the reduction target, there is no limitation to the above.
For example, when the area of the welding portion jmb (jmt) to be reduced is equal to the area of the welding portion jmc that is not the reduction target, the bonding force per unit area of the welding portion jmb (jmt) to be reduced By making (N / m ² ) smaller than the bonding force (N / m ² ) per unit area of the welded portion jmc that is not the reduction target, the bonding strength (N) of the welded portion jmb (jmt) that is the reduction target May be made smaller than the bonding strength (N) of the welded portion jmc that is not a reduction target. Alternatively, the bonding force (N / m ² ) per unit area of the welding portion jmb (jmt) to be reduced is equal to the bonding force (N / m ² ) per unit area of the welding portion jmc that is not to be reduced. In this case, by reducing the area (m ² ) of the welding portion jmb (jmt) to be reduced to be smaller than the area (m ² ) of the welding portion jmc that is not the reduction target, the welding portion jmb ( The joint strength (N) of jmt) may be smaller than the joint strength (N) of the welded portion jmc that is not a reduction target.
However, as in this example, when the area (m ² ) of the welded portion jmb (jmt) to be reduced is reduced and the bonding force (N / m ² ) per unit area is also reduced, the reduction target This is preferable because the bonding strength (N) of the welded portion jmb (jmt) can be reliably reduced.

In some cases, the ventral side portion 11a and the back side portion 11b may not be peeled off smoothly even at the waist opening 1HB. In that case, the operator of diaper replacement takes off the diaper 1 by breaking the exterior sheet 11 itself. In this regard, in this example, as shown in FIG. 11, the basis weight (g / m) of the portion 11HL that forms the leg opening 1HL in the exterior sheet 11 due to the folding of the ventral outer sheet 13a and the back outer sheet 13b at the trunk opening 1HB. ² ) is smaller than the basis weight (g / m ² ) of the portion 11HB forming the trunk periphery opening 1HB in the exterior sheet 11. Therefore, the operator of diaper replacement can tear the exterior sheet 11 itself relatively easily from the leg opening 1HL, and as a result, the diaper 1 replacement operation can be prevented from being stagnant.

  Furthermore, in this example, as shown in FIG. 6A, only the welding strength (N) of one welded portion jmb closest to the leg opening 1HL is reduced, but the welded portion jm to be reduced in this joint strength is reduced. The number is not limited to one and may be plural. For example, as shown in FIG. 8, when the weld portion jmb closest to the leg opening 1HL is the first weld jmb (corresponding to the first portion), the waist opening 1HL of the first weld jmb The welding strength of the welded portion jm adjacent to the side (corresponding to the second portion, hereinafter also referred to as the second welded portion jmb2) is the same as that of the first welded portion jmb. It may be smaller than the welded parts jmc, jmc.

  Furthermore, the bonding strength (N) of the first welded portion jmb and the second welded portion jmb2 may be aligned with each other, but may not be aligned. For example, the joint strength of the second welded part jmb2 may be set to a magnitude between the joint strength of the first welded part jmb and the joint strength of each of the welded parts jmc located at the longitudinal center. And if it does in this way, about at least 2 welding part jmb and jmb2 located in the vicinity of the leg periphery opening part 1HL, joining strength becomes small as the welding part jm in the position near the leg periphery opening part 1HL. Yes. Therefore, the abdominal side portion 11a and the back side portion 11b can be peeled off smoothly from the leg opening 1HL.

  Note that the above description regarding the welded portions jmb and jmb2 in the vicinity of the leg opening 1HL is the same for the welded portion jm located in the vicinity of the waistline opening 1HB. That is, while referring to FIG. 6A before, it has been stated that the bonding strength of one welded portion jmt closest to the waistline opening 1HB may be reduced, but the number of welded portions jm to be reduced in this bonding strength. Is not limited to one, but may be plural. For example, when the welded part jmt closest to the waistline opening 1HB is the third welded part jmt (corresponding to the third part), the welded part jm adjacent to the leg-holed opening 1HL side of the third welded part jmt. The joint strength of (corresponding to the fourth portion, hereinafter also referred to as the fourth welded portion jmt4) may be reduced in the same manner as the third welded portion jmt.

  Furthermore, the joint strength (N) of the third welded portion jmt and the fourth welded portion jmt4 may be aligned with each other, but may not be aligned. For example, the joint strength of the fourth welded portion jmt4 may be set to a magnitude between the joint strength of the third welded portion jmt and the joint strength of each of the welded portions jmc located at the longitudinal center. And if it does in this way, about at least 2 welding part jmt and jmt4 located in the vicinity of the trunk periphery opening part 1HB, the joint strength jm of the position close | similar to the trunk periphery opening part 1HB will become small. Therefore, the abdomen side portion 11a and the back side portion 11b can be peeled off smoothly from the waistline opening 1HB.

The formation of the joint j having such welds jm, jm... Is realized by an appropriate ultrasonic welding device (not shown). The ultrasonic welding apparatus welds the welding target portion by frictional heat generation by supplying ultrasonic energy to the welding target portion. And the welded part remains on the exterior sheet 11 as welded parts jm, jm.
Such an ultrasonic welding apparatus has, for example, a rail-shaped horn extending in a direction corresponding to the vertical direction (hereinafter also referred to as a CD direction). The horn has an oscillation surface that performs ultrasonic vibration. The oscillation surface has a belt-like plane extending in the CD direction, and ultrasonically vibrates at a predetermined frequency such as 20 to 35 kHz in the normal direction. The apparatus also has a roller-shaped anvil (hereinafter referred to as an anvil roller) that can roll the belt-like plane of the horn in the CD direction. On the outer peripheral surface of the anvil roller, a plurality of protrusions are provided in correspondence with the formation pattern of the welded portions jm, jm. Then, the exterior sheet 11 is placed on a belt-like plane that is the oscillation surface of the horn so that the longitudinal direction of the exterior sheet 11 folded in two to form a pants shape is aligned with the CD direction, and the horn is subjected to ultrasonic vibration. While the anvil roller is traversing the exterior sheet 11 along the CD direction, a plurality of welded parts jm, jm... Are formed on the exterior sheet 11 as joints j. At the time of crossing, the ultrasonic energy (J / m) input per unit length in the CD direction is adjusted so as to be small at the portion of the exterior sheet 11 that is closest to the leg opening 1HL. As a result, the bonding strength (N) of the welded portion jmb closest to the leg opening 1HL is selectively reduced. In addition, as a method of changing the magnitude of ultrasonic energy (J / m), changing the amplitude of ultrasonic vibration, changing the pressing force of the anvil roller to the horn, and between the horn and the anvil roller It is possible to exemplify changing the interval.

=== Other Embodiments ===
As mentioned above, although embodiment of this invention was described, said embodiment is for making an understanding of this invention easy, and is not for limiting and interpreting this invention. Further, the present invention can be changed or improved without departing from the gist thereof, and needless to say, the present invention includes equivalents thereof. For example, the following modifications are possible.

  In the above-described embodiment, as an example of the plurality of welded portions jm, jm... That the joint j in FIG. 2 has, a substantially rectangular welded portion jm that is long in the horizontal direction is illustrated as shown in FIG. The shape of is not limited to this. For example, it may be oval or circular. Further, the welding pattern formed as a whole by the plurality of welded portions jm, jm... Is not limited to a simple vertically arranged pattern in which the welded portions jm, jm. For example, it may be a grid pattern in which circular welds are arranged in a grid pattern, or a solid pattern in which the welds are continuous in a strip shape over substantially the entire length in the longitudinal direction of the joint j. There may be other patterns.

In the above-described embodiment, the two-piece type diaper 1 is illustrated in which the absorbent main body 3 as the first part is covered with the exterior sheet 11 having a substantially hourglass shape in plan view as the second part from the non-skin side. Not limited to this. For example, you may form the above-mentioned junction part j which concerns on this invention with respect to what is called a 3 piece type diaper. Details are as follows.
First, as shown in FIG. 9, the diaper has an absorbent main body 3 disposed between the wearer's crotch as a first component, and a ventral belt member disposed on the abdomen side of the wearer as a second component. It has 21a, and has back side belt member 21b arranged on the back side of the wearer as the 3rd part. Further, in the deployed state of FIG. 9, the abdominal band member 21a and the dorsal band member 21b are arranged in parallel with a space between each other, while the absorbent main body 3 is stretched between them, End portions 3ea and 3eb in the longitudinal direction of the absorbent main body 3 are bonded and fixed to the nearest belt members 21a and 21b, respectively, and the external shape thereof is substantially H-shaped in plan view. Then, from this developed state, the absorbent main body 3 is folded in half at a substantially central portion in the longitudinal direction, and the band members 21a and 21b that are overlapped with each other in the folded state are widths orthogonal to the longitudinal direction. When joined at each end in the direction (corresponding to the lateral direction), the band members 21a and 21b are connected in an annular shape, thereby forming a waist opening and a pair of leg openings. It becomes. And the above-mentioned joining part j is applicable also to this joining. Each band member 21a, 21b is formed of a flexible sheet such as a nonwoven fabric including thermoplastic resin fibers. Moreover, since the structure of the absorptive main body 3 is substantially the same as the above-mentioned thing, it abbreviate | omits about the description.

1 diaper (absorbent article), 1HB waistline opening, 1HL leghole opening,
3 Absorbent body, 3ea end, 3eb end,
3c absorbent core, 4 top sheet, 5 leak-proof sheet,
11 exterior sheet, 11HB waist opening part,
11HBa The edge that becomes the waistline opening, 11HBb The edge that becomes the waistline opening,
11HL The leg opening part,
11a ventral side, 11b dorsal side, 11c crotch,
12 body sheet, 12a ventral side, 12b dorsal side, 12c crotch,
12eLa edge, 12eLb edge,
13a ventral side outer sheet, 13ak folded portion, 13ap protruding part,
13b Dorsal side outer sheet, 13bk folded part, 13bp protruding part,
15 Rubber thread (elastic member),
21a ventral band member, 21b dorsal band member,
j joint, jm weld,
jmb first welded portion (first portion), jmb2 second welded portion (second portion),
jmc welding part (predetermined part),
jmt third welded portion (third portion), jmt4 fourth welded portion (fourth portion),
Njm part,
S measurement sample,

Claims (4)

An absorbent article having an abdominal side portion arranged on the abdomen side of the wearer at the time of wearing, a back side portion arranged on the back side of the wearer, and a crotch portion arranged between the crotch of the wearer. In the state where the abdomen and the dorsal part are overlapped by folding in two at the crotch part, the abdomen and the dorsal part are joined at respective lateral ends. A pants-type absorbent article in which a waist opening and a pair of leg openings are formed,
Each joint formed at each end in the lateral direction to join the abdomen and the dorsal side is respectively from the waistline opening to the leghole opening. Extended,
Of at least one of the joints, the joint strength of the first part closest to the leg opening is between the first part and the waist opening of the joint. Smaller than the bonding strength of the predetermined part located ,
The joint has a second portion adjacent to the waist opening side of the first portion,
The bonding strength of the second portion is a size between the bonding strength of the first portion and the bonding strength of the predetermined portion,
Of the joints, the joint strength of the third part closest to the waistline opening is smaller than the joint strength of the predetermined part,
The joint portion includes a fourth portion adjacent to the leg opening portion side of the third portion,
The pants-type absorbent article , wherein the bonding strength of the fourth portion is a size between the bonding strength of the third portion and the bonding strength of the predetermined portion . The pant-type absorbent article according to claim 1 ,
A pants-type absorbent article, wherein the bonding strength of the first portion is smaller than the bonding strength of the third portion. The pant-type absorbent article according to claim 1 or 2 ,
The basis weight (g / m ² ) of the part that forms the leg opening in the ventral part and the dorsal part is the basis weight (g / m ² ) of the part that forms the waist opening in the ventral part and the dorsal part ( A pants-type absorbent article characterized by being smaller than g / m ² ). A pant-type absorbent article according to any one of claims 1 to 3 ,
Both of the joints have the first part and the predetermined part, respectively.

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