JP4747071B2 - Pants-type disposable diaper - Google Patents

Description

  The present invention includes a front body, a crotch part, and a back body, each of which includes an excrement absorbing absorber and includes a lower end of a sheet material (front body sheet) that constitutes the front body and a rear body. The lower end of the (back body sheet) extends below the lower crotch, and the front body sheet and the inner thigh side edge, the outer thigh side edge and the crotch lower end of the back body sheet are joined, Disposable diapers of so-called boxer pants (boxer briefs) type in which an inner thigh side joint, outer thigh side joint, crotch joint, one waist opening, a pair of leg openings and a leg cover are formed It is about.

  The pants-type disposable diaper is composed of the front body 2, the crotch 4, and the back body 6, as in the pants-type disposable diaper 100 shown in FIG. 3, and the corresponding sides of the front body 2 and the back body 6. Edges are joined together to form a waist opening 10 and a pair of leg openings 12 (12a, 12b), and is a disposable diaper provided with an absorbent for absorbing excrement. In such a pants-type disposable diaper, elastic materials such as rubber thread (the elastic material 42 around the waist and the elastic material 40 around the legs) are provided along the waist opening 10 and the leg openings 12 (12a, 12b). The arrangement is common (for example, see Patent Document 1).

  The pants-type disposable diaper can be worn by the wearer in the same way as wearing cloth pants. In addition to being able to change the diaper in a short time, the diaper can be changed while the wearer is standing. Can also be done. In addition, unlike a tape-type diaper, there is no need to adjust the size around the waist with a fixing tape, and the diaper can be easily replaced.

  Incidentally, the pants-type disposable diaper 100 shown in FIG. 3 is a so-called brief pants-type disposable diaper, and leg opening portions 12 a and 12 b are formed in the vicinity of the side edge of the crotch 4. Therefore, there is a problem that a gap is easily formed around the legs (particularly both side edges of the crotch part) by the wearer's movement, and side leakage is likely to occur.

  Therefore, the lower end of the sheet material (front body sheet) constituting the front body and the lower end of the sheet material (rear body sheet) constituting the rear body are extended from the crotch to the lower part, and the front body sheet and the rear body sheet By joining the inner thigh side edge, outer thigh side edge and crotch lower end, the thigh side joint, outer thigh side joint, crotch joint, one waist opening, a pair of legs A so-called boxer shorts (boxer brief) type disposable diaper in which a peripheral opening and a leg periphery covering part are formed has been proposed (see, for example, Patent Documents 2 to 6).

  For example, the disposable diapers described in Patent Documents 2 to 4 are independent members each having a three-layer structure in which a front body and a back body each have a liquid-permeable top sheet, an absorber, and a liquid-impermeable back sheet. The front body and the back body are pasted together to form a boxer pants type.

  The disposable diaper described in Patent Document 5 has a three-layer structure in which the front body and the back body each have a liquid-permeable top sheet, an absorber, and a liquid-impermeable back sheet. The body absorbent body is continuously formed, and the front body and the back body are bonded together to form a boxer pants type.

  Furthermore, the disposable diaper described in Patent Document 6 is configured in the same manner as the disposable diapers described in Patent Documents 2 to 4, and further includes an auxiliary absorber that is bent in a U-shape inside the crotch. Is.

Registered Utility Model No. 3024357 Japanese Utility Model Publication No. 6-16404 JP-A-6-570502 Japanese Utility Model Publication No. 6-63073 JP-A-9-182769 Japanese Utility Model Publication No. 6-21621

  In these disposable diapers, since the leg circumference covering portion is formed, it is difficult to form a gap around the leg (particularly, both side edges of the crotch), and it can be expected to reduce the occurrence of side leakage. However, since these disposable diapers have high adhesion between the leg covering portion and the wearer's skin, the diaper breaks when the diaper is worn, or pain occurs in the leg during walking. There was a problem that the feeling of wearing was bad, and there was room for improvement.

  Thus, at present, the boxer underpants type disposable diaper that can effectively prevent breakage of the diaper when wearing the diaper, is less likely to cause pain in the leg during walking, and has a good wearing feeling. It has not yet been disclosed, and such disposable diapers are eagerly desired.

  The present invention has been made to solve such problems of the prior art, and can effectively prevent the diaper from being broken when the diaper is worn, and can cause pain in the leg during walking. The present invention is to provide a boxer pants-type disposable diaper that is less and has a good wearing feeling.

  As a result of diligent studies to solve the problems of the prior art as described above, the injuries of the inner leg side where the leg pain at the time of diaper breakage or walking forms the leg circumference covering portion, The knowledge that it is related to the joint strength of the outer thigh side joint was obtained. And the above-mentioned subject is made by making the difference in the joint strength between the crus side joint part and the crus side joint part of the diaper and making the joint strength of the joint part on the crus side higher than the joint part on the crus side. As a result, the present invention has been completed. Specifically, the following pant-type disposable diapers are provided by the present invention.

[1] The lower part of the sheet material (front body sheet) that constitutes the front body, and the lower end of the sheet material (rear body sheet) that constitutes the rear body are composed of the front body, the crotch part, and the back body. While extending from the crotch to the lower part, the inner thigh side edge, the outer thigh side edge and the crotch lower end of the front body sheet and the back body sheet are joined, An outer thigh side joint, a crotch joint, a waist opening, a pair of leg openings and a leg covering , and each joint point of the inner thigh is formed in a dot shape. The pants-type disposable diaper in which the joint point of the outer thigh side joint is formed in a line shape or a V shape, and the joint strength of the outer thigh side joint is higher than that of the inner thigh side joint.

[2] The pants-type disposable diaper according to the above [1], wherein the joint strength of the outer thigh side joint is higher than that of the crotch joint.

[3] The crus side joint part and the crus side joint part are joined by at least one joint point, and the outer leg side joint part is longer than the perimeter of the joint point of the crus side joint part. The pants-type disposable diaper according to the above [1], wherein the perimeter of the junction point is configured to be long.

[4] The front body, the crotch part, and the back body, each of which comprises an excrement absorbing absorber, the lower end of the sheet material (front body sheet) constituting the front body and the sheet material constituting the rear body (rear) The lower end of the body body sheet) extends downward from the crotch part, and the inner leg side edge, the outer leg side edge and the crotch lower end of the front body sheet and the rear body sheet are joined together An inner thigh side joint, an outer thigh side joint, a crotch joint, a single waist opening, a pair of leg openings and a leg covering, and each joint point of the inner thigh joint is In addition to being formed in a single line, the joint points of the crus joints are formed in a plurality of lines, and the joint strength of the crus joints is higher than that of the crus joints. Pants-type disposable diaper.
[5] Each joint point of the crotch joint part is formed in a dot shape, each joint point of the crus side joint part is formed in a line, and the joint point of the crus joint part is in a plurality of lines. The above-mentioned [4], wherein the joint strength of the crus joint is higher than that of the crotch joint, and the joint strength of the crus joint is higher than that of the crus joint. Pants-type disposable diapers.

[ 6 ] The front body sheet and the back body sheet are made of a nonwoven fabric, and the outer thigh side edge is made of a non-woven fabric having a higher basis weight than the non-woven fabric constituting the inner thigh side edge. The pants-type disposable diaper according to any one of [1] to [5] .

[ 7 ] The pants-type disposable diaper according to any one of [1] to [6] , wherein a joint strength of the inner thigh side joint is 3.0 N / 25 mm to 20.0 N / 25 mm.

[ 8 ] The pants-type disposable diaper according to any one of [1] to [7] , wherein the joint strength of the outer thigh side joint is 7.0 N / 25 mm to 30.0 N / 25 mm.

The pants-type disposable diaper of the present invention is configured so that the joint strength of the outer thigh side joint is higher than the inner thigh side joint, and therefore can effectively prevent breakage of the diaper when wearing the diaper, There is little pain in the legs during walking, and the wearing feeling is good.

  Hereinafter, the best mode for carrying out the pants-type disposable diaper of the present invention will be specifically described with reference to a so-called two-piece type boxer pants-type disposable diaper. However, the present invention broadly encompasses pants-type disposable diapers having the invention-specific matters, and is not limited to the following embodiments.

  The “two-piece type” means an absorbent main body 14 that functions to absorb and retain the excrement of the wearer (absorption / retention function) as in the pants-type disposable diaper 1 shown in FIGS. 1 and 2. And the exterior member 16 which bears the function (mounting function) which encloses a wearer's body, The diaper of the type by which the absorptive main body 14 was arrange | positioned inside the exterior member 16 shall be meant. As shown in FIG. 2, the absorbent main body 14 is a member that includes an absorbent body 22, a top sheet 18, and a back sheet 20 as components.

  Further, in the present specification, the term “pants-type disposable diaper” includes an absorbent for absorbing excrement as in the pants-type disposable diaper 100 shown in FIG. 3, and the corresponding side of the front body 2 and the back body 6. By joining the edge portions, a joint portion 8, one waist opening portion 10, and a pair of leg opening portions 12a and 12b are formed, which means a diaper configured in a pant shape in advance.

  And the “boxer pants type” is a sheet material (front body) that constitutes the front body 2 like the pants type disposable diaper 1 shown in FIGS. 1 and 2 among the above “pants type disposable diapers”. The lower end of the sheet) and the lower end of the sheet material (rear body sheet) constituting the back body 6 are extended downward from the crotch part 4 and the outer side edge of the front body sheet 30 and the back body sheet 32, outside By joining the thigh side edge and the crotch part 4, the inner thigh side joint 8b, the outer thigh side joint 8a, the crotch joint 8c, one waist opening 10, and a pair of leg openings 12a. 12b and leg-surrounding covering portions 24a and 24b are formed.

  In addition, in this specification, “front body” means a part that covers the abdomen (front of the body) of the wearer when a diaper is worn on the wearer, and “inseam” means that the wearer wears a diaper. When the wearer wears a diaper, the part covering the inseam of the wearer means the part covering the back side (back of the body) of the wearer.

[1] Configuration of the pants-type disposable diaper of the present invention:
The pants-type disposable diaper of this invention is comprised from each part of the front body 2, the crotch part 4, and the back body 6 like the pants-type disposable diaper 1 shown in FIG.1 and FIG.2, and the absorber 22 for excrement absorption. The lower end of the sheet material (front body sheet 30) constituting the front body 2 and the lower end of the sheet material (rear body sheet 32) constituting the rear body 6 are extended below the crotch part 4 and the front body By joining the inner leg side edge part, outer leg side edge part and crotch lower end part of the seat 30 and the back body sheet 32, the inner leg side joint part 8b, the outer leg side joint part 8a, and the crotch joint part 8c. , One waist opening 10, a pair of leg openings 12a and 12b, and leg coverings 24a and 24b are formed, and the joint strength of the outer thigh side joint 8a is higher than the inner thigh side joint 8b. It is what has been .

  When a diaper is worn, the diaper breaks often because a fragile joint peels even in the diaper. Therefore, it can be expected that this problem can be solved if the bonding strength of the bonding portion is high. However, if the entire joint is constructed with a high joint strength, a hard joint with high joint strength is formed on the inner thigh side, and this part rubs during walking, causing pain to the wearer's leg. May occur. Then, when this inventor wears a diaper, in order to perform the operation | movement of pulling up with the side edge side of a diaper, it paid attention to the point that the largest force was applied to the side edge side of a diaper. In other words, it is not necessary to configure the joint part with a uniform high joint strength, and the joint strength between the joint part on the inner thigh side and the joint part on the outer thigh side of the diaper is different, so The idea was to increase the joint strength at the thigh joint. In this way, the outer thigh side joint where the force is most applied when the diaper is worn can be configured with a high joint strength, and the diaper can be effectively prevented from breaking when the diaper is worn, and the flexibility of the joint is also achieved. Therefore, it is possible to make the leg feel less worn by walking with a relatively low joint strength for the inner thigh side joint, which is required, to improve the feeling of wearing.

In the pants-type disposable diaper of the present invention, in addition to configuring the joint strength of the outer thigh side joint part higher than the thigh side joint part, the joint strength of the thigh side joint part is configured to be higher than the crotch joint part. Is also preferable. If a hard joint is formed on the delicate crotch part, it may become stiff or feel foreign. According to the configuration as described above, it is possible to eliminate the crotch inferiority and the feeling of foreign matter and obtain a comfortable wearing feeling. For example, the pants-type disposable diaper 1 shown in FIG. 1 has a crotch joint portion 8c formed by a set of dot-like joint points 34b having a relatively low joint strength, like the inner thigh side joint portion 8b. This is an example in which the bonding strength is lower than that of the outer thigh side bonding portion 8a formed by a set of line-shaped bonding points 34a having high bonding strength.

  However, in the pants-type disposable diaper of the present invention, it is only necessary that the joint strength of the outer thigh side joint portion is higher than that of the crotch joint portion, and the joint strength of the crotch joint portion and the inner thigh side joint portion is not necessarily equal. For example, the pants-type disposable diaper 110 shown in FIG. 6 has a double row line-shaped joint point 36a for the outer thigh side joint 8a and a joint strength lower than the joint point 36a for the inner thigh side joint 8b. This is an example in which a line-shaped joint point 36c is arranged and the crotch joint part 8c is a dot-like joint point 36d having a joint strength lower than that of the joint point 36c. In the illustrated configuration, the joint strength of the crotch joint portion 8c can be made lower while securing the joint strength of the inner thigh side joint portion to some extent, and the effect of eliminating the stiffness of the crotch portion 4 and the feeling of foreign matter can be further improved. Can be improved.

  In this specification, when “the joint strength of the outer thigh side joint is higher than the inner thigh side joint”, the end of the inner leg side joint on the leg opening side (the thigh side joint) It means that the joint strength at the end of the outer leg side joint portion on the leg opening side (the lower end portion of the outer leg side joint portion) is higher than the joint strength at the lower end portion.

  Further, the “joining strength” means the tensile strength measured by the method shown in FIG. 4A is a schematic front view schematically showing a pant-type diaper, FIG. 4B is an enlarged view of the outer thigh side test piece, and FIG. 4C is an expanded view of the outer thigh side test piece. It is a schematic side view which shows typically the state fixed with the chuck | zipper.

  First, as shown in FIGS. 4A and 4B, each of the outer thigh side joint portion 8a and the inner thigh side joint portion 8b of the pants-type disposable diaper 70 has a predetermined shape (w: 25 mm). × l: 30 mm) and cut into outer thigh side test piece 72 and inner thigh side test piece 74.

Next, the outer thigh side test piece is set on a tensile tester (trade name: Strograph V1-B, manufactured by Toyo Seiki Seisakusho Co., Ltd.). As shown in FIG. 4 (c), the outer thigh side test piece is set such that the outer thigh side test piece 72 is developed left and right with the outer thigh side joint portion 8a being the center, and the developed ends are vertically moved. Then, it is fixed by sandwiching with a chuck 76. At this time, the distance (d) between the left and right chucks is 20 mm. In this state, the tensile tester is operated, and the tensile strength of the outer thigh side test piece 72 is measured by pulling the outer thigh side test piece 72 in the left-right direction. At this time, the tensile speed is 200 mm / min, and the measurement is terminated when the outer thigh side test piece 72 is broken.
Finally, the maximum tensile strength is confirmed from the obtained measurement chart. This maximum tensile strength is referred to as “joining strength” in the present specification. The “joining strength” can be measured in the same manner for the inner thigh side joint.

[1-1] Joint part:
In the pants-type disposable diaper of the present invention, the inner thigh side joint, the outer thigh side joint, and the crotch joint are joined by at least one joining point. Here, the “joining point” means a part where the front body sheet and the back body sheet are actually joined, and the “joining part” means a region where at least one or more of the joining points exist. Shall. For example, the pants-type disposable diaper 1 shown in FIG. 1 is formed by a plurality of line-shaped joint points 34a for the outer thigh side joint portion 8a, and a plurality of dot-like shapes for the inner thigh side joint portion 8b and the crotch joint portion 8c. The junction point 34b is formed.

The pants-type disposable diaper of the present invention is configured such that the joint strength of the outer thigh side joint is higher than that of the inner thigh side joint. It is formed, and the joint point of the outer leg side joint part is formed in a line shape or a V shape (first embodiment), or 2) each joint point of the inner leg side joint part is in a line shape In addition, it is necessary that the joint points of the outer leg side joint portion are formed in a plurality of lines (second embodiment). By adopting the first embodiment or the second embodiment, it is possible to make a difference in joint strength between the inner thigh side joint and the outer thigh side joint. However, after satisfying the requirements of the first embodiment or the second embodiment, it is possible to join by appropriately setting the requirements other than the requirements of the first embodiment or the second embodiment as listed below. You may make a difference in strength.

[1-1a] Form of junction point:
The joint strength of the joint can be controlled by the form (pattern and shape) of the joint points. For example, even if the joint points of the inner thigh side joint part and the outer thigh side joint part have the same shape, the joint strength of both joint parts can be increased by changing the arrangement density (number per unit area) of the joint points. It is possible to make a difference. Referring to FIG. 5, the pattern (a) and the pattern (b) in FIG. 5 are the same in the shape of the junction points, but the pattern (a) has a higher arrangement density of junction points, and the pattern It can be said that the bonding strength is higher than in (b). However, if the arrangement density becomes too high, the joint point functions for the purpose of the sewing machine, and the joint portion may be easily broken. Therefore, it is preferable to arrange each joining point at intervals of at least 0.8 mm.

  Moreover, it is possible to control the joint strength of the joint part by the number of joint points. The pattern (c) in FIG. 5 has horizontal linear joining points like the pattern (a), but the joining points are arranged in two rows, and the number of joining points is increased. It can be said that the bonding strength is higher than that of the pattern (a). For the same reason, it can be said that the bonding strength of the pattern (e) is higher than that of the pattern (d), and that the bonding strength of the pattern (i) is higher than that of the pattern (h). For example, in the pants-type disposable diaper 110 shown in FIG. 6, the outer thigh side joint portion 8a and the inner thigh side joint portion 8b form a joint portion with line-shaped joint points. This is an example in which one line-line joint points 36c are arranged (pattern (a) in FIG. 5), and the outer leg side joint portion 8a is arranged in two rows line-like joint points 36a (pattern (c) in FIG. 5). ). In the pattern (c) in FIG. 5, the joining points are arranged in two rows, but it is possible to further increase the joining strength by arranging three or more rows.

  When two or more rows of junction points are arranged, it is not always necessary to arrange the junction points of each row in the same pattern as in the patterns (c) and (e). For example, as in the pattern (i), the direction of the junction points in each column may be different, or the positions of the junction points in the height direction may be shifted.

  Furthermore, it is possible to control the bonding strength of the bonded portion depending on the size of the area of the bonding point. The pattern (l) in FIG. 5 has dot-like (circular) junction points as in the pattern (k), but the junction area of one junction point is larger than the pattern (k). It can be said that the strength is high.

  Moreover, the joint strength of both joint parts can also be made different by making the shape of the joint point of the inner thigh side joint part and the outer thigh side joint part different. For example, it is possible to increase the joint strength of the outer leg side joint by configuring the circumference of the joint point of the outer leg side joint to be longer than the circumference of the joint point of the inner leg side joint. The longer the peripheral length of the joint point, that is, the outer peripheral length of the joint point, the larger the joint area at one joint point, and the joint strength can be increased. In addition, in the joining method such as heat sealing, the center part of the joining point melts and melts down, and the joining point may become a ring shape, but even in such a case, the circumference of the ring shape is long. Insofar as the joint strength is increased. This is because in the joining method such as heat sealing, the vicinity of the outer edge of the joining point can be said to be a substantial joining point.

  As a specific form of configuring the circumference of the joint of the outer thigh side joint longer than the circumference of the joint of the inner thigh side joint, for example, each joint of the inner thigh side joint is formed in a dot shape. It can be formed and the joint point of the outer thigh side joint can be formed in a line shape or a V shape. For example, the pants-type disposable diaper 1 shown in FIG. 1 is an example in which each joint point 34b of the inner thigh side joint portion 8b is formed in a dot shape and each joint point 34a of the outer thigh side joint portion 8a is formed in a line shape. In the pants-type disposable diaper 120 shown in FIG. 7, each joint point 38b of the inner thigh side joint portion 8b is formed in a dot shape, and the joint point 38a of the outer thigh side joint portion 8a is formed in a lateral V-shape. This is an example. In the example of FIG. 1, the line-shaped junction point 36a is arranged so as to be inclined so that the side edge side of the diaper is high and the center side is low. In the example of FIG. It is arranged sideways so that the characters are open toward the side edge of the diaper.

  In addition, it is not necessary to make all joint points into the same shape in the inner thigh side joint portion and the outer thigh side joint portion, and those having different shapes may be combined. For example, the pattern (m) in the figure is an example in which horizontal linear junction points are densely arranged in the end region of the junction portion, and a horizontal V-shaped junction point is arranged in the central region. In the pants-type diaper, the end portion of the joint portion is likely to be the starting point of breakage, and more joint strength is required, whereas the central region of the joint portion does not require a large joint strength. Accordingly, it is one of preferred modes to arrange the horizontal linear junction points densely in the end region of the junction as in the pattern (m).

  For example, the pants-type disposable diaper 110 shown in FIG. 6 has two rows of line-like joining points 36a (pattern (c) in FIG. 5) arranged in the end region of the outer thigh side joint 8a. In the central region of the portion 8a, a line-line joint point 36b is disposed (pattern (a) in FIG. 5).

  By the way, as shown in FIG. 8B, considering the case of continuously producing diapers using a long sheet, the shape of the joining point should be a shape along the flow direction of the long sheet. Is preferred. By setting it as such a shape, it becomes difficult for fiber residue etc. to accumulate in the vicinity of a joining point, and the operativity of continuous manufacture can be improved.

  For example, both of the pants-type disposable diaper 1 shown in FIG. 1 and the pants-type disposable diaper 130 shown in FIG. 9 have the outer thigh side joint portion 8a formed by line-like joint points 34a and 46a. However, according to the manufacturing method shown in FIG. 8B, since the long sheet flows in the left and right direction of the diaper, the junction 46a of the pants-type disposable diaper 130 shown in FIG. It is formed in the shape of a line orthogonal to each other, and it can be said that it is a shape in which fiber debris or the like tends to accumulate near the junction. On the other hand, the joining point 34a of the pants-type disposable diaper 1 shown in FIG. 1 is formed in a line shape along the flow direction of the long sheet, although having a certain inclination. Therefore, fiber debris and the like are unlikely to collect in the vicinity of the joining point, and there is an effect that the operability of continuous production can be improved.

  In the present specification, the term “shape along the flow direction of the long sheet” does not necessarily have to be formed in a direction parallel to the flow direction of the long sheet. If it is formed in a direction inclined within a range of 45 °, it is allowed. For example, in the pants-type disposable diaper 1 shown in FIG. 1, the joining point 34a is inclined by 30 ° with respect to the flow direction of the long sheet (that is, the direction parallel to the edge of the diaper around the waist). It is an example formed along.

[1-1b] Selection of material:
The joint strength of the joint can be controlled by selecting the material. For example, when the front body sheet and the back body sheet are made of non-woven fabric, by configuring the outer thigh side edge with a non-woven fabric having a higher weight than the non-woven fabric constituting the inner thigh side edge, The joint strength of the outer thigh side joint can be configured to be higher than that of the inner thigh side joint.

  In addition to the basis weight of the nonwoven fabric as described above, the bonding strength can be controlled by selecting the material and the like. For example, in a joining method involving heating such as heat sealing, if the same material having the same melting point is selected as the front body sheet and the back body sheet, the joining strength can be made higher than when different materials are selected. . This is because, when the same material is used, the degree of melting when heated is similar, so that both sheets are easily fused. Moreover, even when the same material is selected as the front body sheet and the back body sheet, for example, polyethylene is easier to melt and fuse than polypropylene, and the bonding strength can be increased.

  As shown in FIG. 8B, in the case where diapers are continuously manufactured using a long sheet, it is difficult to change the material between the inner thigh side edge and the outer thigh side edge. However, in such a case, for the purpose of changing the bonding strength between the front body sheet and the back body sheet, a sheet having desired characteristics is sandwiched, and the same effect is obtained by joining the parts. be able to. For example, when the front body sheet and the back body sheet are made of the same material, a sheet made of a different material is sandwiched only at the inner thigh side edge where the bonding strength is desired to be reduced, and heat sealing or the like is performed. , The bonding strength of the portion can be lowered. Contrary to this, the front body sheet and the back body sheet are made of the same material, and a sheet made of a resin having a low melting point such as polyurethane is sandwiched only at the outer leg side edge where the bonding strength is desired to be increased. By performing bonding such as heat sealing, the bonding strength of the portion may be increased. This is because a resin having a low melting point acts as an adhesive and firmly joins the front body sheet and the back body sheet.

[1-1c] Presence or absence of adhesive:
The joint strength of the joint can be controlled by the presence or absence of an adhesive at the joint. For example, when the bonding portion is bonded by heat bonding such as heat sealing or heat embossing, if an adhesive is applied to the portion to be bonded, the thermal conductivity of the portion decreases, or the front body sheet and The bonding strength is reduced due to reasons such as melting / mixing with the back body sheet, and thus hindering fusion. Accordingly, by intentionally applying the adhesive only to the inner thigh side edge where the bonding strength is desired to be lowered, the bonding strength of that portion can be lowered.

[1-1d] Joining conditions:
In addition, the bonding strength of the bonded portion can be controlled by the bonding condition of the bonded portion. This point will be described in the section of the manufacturing method.

[1-1e] Specific value of bonding strength:
In the pants-type disposable diaper of the present invention, the joint strength of the inner thigh side joint is preferably 3.0 N / 25 mm to 20.0 N / 25 mm. If the joint strength of the inner thigh side joint is less than 3.0 N / 25 mm, the joint strength becomes too low, and the inner thigh side joint may be peeled depending on the wearer's movement. On the other hand, when it exceeds 20.0 N / 25 mm, the inner thigh side joint portion is hardened, and the hardened thigh side joint portion rubs during walking, which may cause pain in the wearer's leg.

  In addition, the preferable range of the joint strength of the inner thigh side joint portion is a so-called infant pant diaper (having a circumference of 650 to 850 mm in the stretched state of the waist opening) and an adult pant diaper (waist The peripheral length in the extended state of the surrounding opening is slightly different from the case of 900-1700 mm. In the case of an infant pants-type diaper, since the skin of the infant is delicate, it is preferable to set the joint strength of the joint part on the inner thigh to a lower range in the above range. Specifically, the joint strength of the inner thigh side joint is preferably 3.0 N / 25 mm to 15.0 N / 25 mm, more preferably 5.0 N / 25 mm or more and less than 10.0 N / 25 mm. . On the other hand, in the case of an adult pant-type diaper, an adult whose skin is stronger than that of an infant is used. Therefore, the bonding strength may be set to be slightly higher than that for an infant. Specifically, the joint strength of the inner thigh side joint is preferably 3.0 N / 25 mm to 20.0 N / 25 mm, and more preferably 5.0 N / 25 mm or more and less than 15.0 N / 25 mm. .

  In the pants-type disposable diaper of the present invention, it is preferable that the joint strength of the outer thigh side joint is 7.0 N / 25 mm to 30.0 N / 25 mm. When the joint strength of the outer thigh side joint is less than 7.0 N / 25 mm, the joint strength becomes too low, and when the diaper is worn, the side thigh side joint is peeled off when pulled up. Or it may be broken and the whole diaper may be broken. On the other hand, if it exceeds 30.0 N / 25 mm, there is a possibility that even if the outer thigh has a stronger skin than the inner thigh, the joint portion hits the skin and feels pain. In order to easily remove the pant-type diaper from the wearer, the side edge of the diaper is torn, but this is the case when the joint strength of the outer thigh side joint exceeds 30.0 N / 25 mm. It may be difficult to tear the side edges.

  In addition, the preferable range of the joint strength of the outer thigh side joint is also slightly different between the case of the infant pants-type diaper and the case of the adult pants-type diaper. In the case of a pants-type diaper for infants, since the load applied when pulling up the diaper is not so high, the joint strength of the outer thigh side joint may be set to a lower range in the above range. Specifically, the joint strength of the outer thigh side joint is preferably 7.0 N / 25 mm to 25.0 N / 25 mm, and more preferably 10.0 N / 25 mm or more and less than 20.0 N / 25 mm. . On the other hand, in the case of an adult pants-type diaper, since the load applied when the diaper is pulled up is high, it is preferable to set the bonding strength to a slightly higher range than that for an infant. Specifically, the joint strength of the outer thigh side joint is preferably 9.0 N / 25 mm to 30.0 N / 25 mm, more preferably 15.0 N / 25 mm or more and less than 25.0 N / 25 mm. .

[1-2] Absorber:
The absorber is a member for absorbing and holding the wearer's urine. The absorber is made of an absorbent material because it needs to absorb and retain the wearer's urine and body fluid.

  Examples of the absorbent material constituting the absorber include conventionally known absorbent materials usually used for disposable diapers and other absorbent articles, such as fluff pulp, super absorbent polymer (Super Absorbent Polymer; hereinafter referred to as “SAP”). And a hydrophilic sheet. It is possible to use wood pulp or non-wood pulp defibrated as fluff pulp, sodium polyacrylate as SAP, tissue, absorbent paper, hydrophilized nonwoven fabric as hydrophilic sheet preferable. In addition, in order to prevent the shape of the absorbent body from being lost, the absorbent body may be configured by adding synthetic fibers such as heat-sealing fibers in addition to natural fibers such as fluff pulp.

  These absorbent materials are usually used as a single-layer or multi-layer mat. Under the present circumstances, 1 type may be used independently among the said absorptive materials, and 2 or more types may be used together. Especially, what used together about 10-500 mass parts SAP with respect to 100 mass parts of fluff pulp is preferable. At this time, the SAP may be uniformly mixed in each mat of fluff pulp, or may be arranged in layers between the layers of the multilayer fluff pulp.

  It is preferable that the absorber is interposed at least in part between the top sheet and the back sheet. Usually, the absorber is interposed between the top sheet and the back sheet by being sandwiched between the top sheet and the back sheet and sealing the peripheral edge thereof. Therefore, the flap part in which the absorber is not interposed is formed between the top sheet and the back sheet at the peripheral part of the absorber.

  It is preferable that the absorber is entirely wrapped with a hydrophilic sheet. Such a configuration has an advantage that SAP can be prevented from leaking from the absorber and shape stability can be imparted to the absorber.

  Although there is no restriction | limiting in particular about the shape of an absorber, The shape used in the conventional disposable diaper and other absorbent articles, for example, a rectangular shape, an hourglass type, a gourd type, a T shape etc. can be mentioned.

[1-3] Top sheet:
A top sheet is a sheet | seat arrange | positioned so that the surface (surface located in a wearer's skin side at the time of mounting | wearing of a diaper) may be coat | covered. At least a part (all or a part) of the top sheet is made of a liquid-permeable material because the absorber disposed on the back surface side needs to absorb the wearer's urine.

  Examples of the liquid permeable material constituting the top sheet include a woven fabric, a nonwoven fabric, and a porous film. Among them, it is preferable to use a non-woven fabric made of a thermoplastic resin such as polyolefin (polypropylene, polyethylene, etc.), polyester, aliphatic polyamide (so-called nylon), etc., which has been subjected to a hydrophilic treatment. The top sheet may be composed of a single sheet material, but may be composed of a plurality of sheet materials.

[1-4] Backsheet:
A backsheet is a sheet | seat arrange | positioned so that the back surface (surface located in a wearer's clothing side at the time of mounting | wearing of a diaper) may be coat | covered. The back sheet is made of a liquid-impermeable material because it is necessary to prevent the wearer's urine from leaking outside the diaper.

  Examples of the liquid-impermeable material constituting the backsheet include a liquid-impermeable film made of a resin such as polyethylene. Among these, a microporous polyethylene film is preferably used. This microporous polyethylene film has a large number of fine pores of 0.1 to several μm, and is liquid impervious but has moisture permeability, so that the inside of the diaper can be prevented from being steamed There is.

[1-5] Absorbent body:
The pants-type disposable diaper of the present invention may be a one-piece type pants-type diaper such as the disposable diapers described in Patent Documents 2 to 4, but absorbs and holds the topsheet, the backsheet, and the absorbent body. It is preferably a so-called two-piece type pants-type diaper that is configured as a single member called an “absorbent body” that bears the function, and is bonded to an exterior member that is manufactured separately. This absorbent main body has a structure in which a top sheet is disposed on the front surface side of the absorbent body and a back sheet is disposed on the back surface side, and the absorbent body is interposed between the top sheet and the back sheet. For example, the pants-type disposable diaper 1 shown in FIG. 2 sandwiches the absorbent body 22 between the top sheet 18 and the back sheet 20 and seals the periphery of the absorbent body 22, whereby the top sheet 18 and the back sheet 20. It is the example which comprised the absorptive main body 14 of the structure where the absorber 22 was interposed in between.

  The “one-piece type pants-type diaper” includes a top sheet, a back sheet, and an absorbent body, but the absorbent body that absorbs and retains is interposed between the top sheet and the back sheet (built-in). It means a diaper of a type integrally formed with a top sheet and / or a back sheet that bears the mounting function.

  An absorptive main body is comprised by the size which covers at least the crotch part of a diaper. However, in order to ensure the effect of preventing leakage, it is preferable to have a size that covers not only the crotch part but also a part of the front body and the back body. In the pants-type disposable diaper of the present invention, it is preferable that the absorbent main body is configured to be narrower than the exterior member in the crotch part. By adopting such a configuration, the absorbent main body that protrudes from the opening around the leg does not hinder the insertion of the leg into the opening around the leg, making it easy to wear the diaper, There is an advantage that the fit of the part is excellent. In addition, the absorptive main body can be fixed to the exterior member using, for example, a hot melt adhesive.

  Further, when the pants-type disposable diaper of the present invention is a so-called two-piece type pants-type diaper, the absorbent main body may be configured to be divided on the front body side and the back body side, It is preferable that the members are continuously arranged from the front body to the back body. By doing so, the seam of the absorbent body is not formed in the crotch part, and the problem of seeping out and leakage along the seam can be solved.

[1-6] Exterior member:
The exterior member is a member having a mounting function for encapsulating the wearer's body, and specifically, is a sheet-like member that forms the front body, the crotch portion, and the back body.

  In the two-piece type disposable diaper, the absorbent main body serves exclusively for the absorption and holding function of absorbing and holding the wearer's excrement, so a liquid-impermeable material as a material constituting the exterior member There is no need to use. In the pants-type disposable diaper of the present invention, the exterior member is preferably made of a nonwoven fabric. Although the kind of nonwoven fabric is not specifically limited, For example, the nonwoven fabric etc. which were comprised by the synthetic fiber which consists of polyolefin (polyethylene, polypropylene, etc.), polyester, aliphatic polyamide (what is called nylon), and another thermoplastic resin can be mentioned. As described above, a nonwoven fabric made of synthetic fibers is often used as a constituent material of the exterior member, but a nonwoven fabric made of natural fibers (for example, cotton) may be used for a part of the exterior member (for example, the inner surface). .

  By providing the exterior member in this way, compared to a one-piece type pants-type diaper, (1) the whole diaper is not sticky, and the wear feeling and fit are good, (2) waist opening and legs When an elastic material is placed in the vicinity of the surrounding opening, the elastic force can be fully applied, leakage from the waist and legs can be effectively prevented, and the diaper can be easily attached and detached. (3) It is possible to obtain an effect that the air permeability is good, the stuffiness inside the diaper is small, and the wearing feeling is good.

  And in order to fix an exterior member in the state which pinched | interposed the elastic material etc. around the leg, it is often configured by bonding two or more nonwoven fabrics together. For example, in the pants-type disposable diaper 1 shown in FIGS. 1 and 2, the exterior member 16 is configured by bonding two nonwoven fabrics, an inner sheet 16a and an outer sheet 16b, and the leg-surround stretchable material 40 is interposed between the nonwoven fabrics. This is an example in which the waist elastic member 42 and the belly elastic member 44 are sandwiched and fixed. In this example, a part of the outer sheet 16b is folded, and the front end and the rear end of the absorbent main body 14 are covered with the pressing sheet 28 sandwiched between the folded portions. Such a configuration is preferable because it is possible to prevent leakage of urine and loose stool from the front end or rear end of the absorbent main body 14 to the outside of the diaper.

[1-7] Leg circumference covering portion:
“Leg circumference covering portion” as used in the present specification is a portion covering a part around the wearer's leg, and means a portion formed below the crotch part of the diaper. The lower end of this is extended from the crotch part to the lower part. In the pants-type disposable diaper of the present invention, the front body, the crotch part, and the back body are formed by an exterior member made of a nonwoven fabric, so that the leg periphery covering part is also formed by a part of the exterior member.

  As long as it is as described above, the shape of the leg-surrounding covering portion is not particularly limited, and examples thereof include shapes as shown in FIGS. 10 (a) to 10 (e).

  As shown in FIGS. 10A and 10B, the leg end openings 12 a and 12 b are formed so that the opening ends thereof are substantially parallel to the opening ends of the waist opening 10. For example, when the manufacturing method as shown in FIG. 8B is adopted, for example, (1) trimming (removal of the trim piece 56) for forming the leg openings 12a and 12b is unnecessary. (2) As shown in FIG. 10 (b), it is not necessary to arrange the leg elastic member 40 in a curved manner in accordance with the shape of the leg circumference opening, and it is sufficient to arrange it in a straight line. Has the advantage of being easy and excellent in productivity.

  Further, as shown in FIG. 10B, when the inner diameter of the leg periphery covering portions 24a and 24b gradually narrows from the crotch part 4 side toward the leg periphery opening portions 12a and 12b, There is an advantage that the change in the thickness of the leg that narrows toward the side and the shape of the leg cover parts 24a and 24b are easily matched, and the fit of the leg cover parts 24a and 24b to the leg is good.

  As shown in FIGS. 10 (c) to 10 (e), the opening end on the outer thigh side is arranged at a higher position than the opening end on the thigh side of the leg opening 12a, 12b. If the shape is formed (a shape in which the outer leg side of the leg opening 12a, 12b is cut off), the opening area of the leg opening 12a, 12b is increased. Therefore, there is an advantage that the leg can be easily inserted into the leg opening portion while the inner leg side where lateral leakage is likely to occur is covered with the leg periphery covering portions 24a and 24b.

  As shown in FIGS. 10 (c) to 10 (e), when the outer leg side of the leg-hole openings 12a and 12b is cut off, the position of the opening end on the outer leg side is not particularly limited. Absent. However, when the lengths of the leg cover portions 24a and 24b are relatively short, as shown in FIG. 10 (d), the leg whose opening end is higher than the crotch part 4 as shown in FIG. It is preferable because the opening areas of the surrounding openings 12a and 12b can be made sufficiently large. On the other hand, when the lengths of the leg periphery covering portions 24a and 24b are relatively long, as shown in FIG. 10 (c), the opening end on the outer thigh side is at a position lower than the crotch part 4, As shown in FIG. 10 (e), the opening area of the leg openings 12a and 12b can be made sufficiently large even when the opening end on the outer thigh side and the height of the crotch part 4 are at the same position.

  Among the shapes shown in FIGS. 10A to 10E described above, (1) since the opening area of the leg opening 12a, 12b can be made relatively large, it is easy to wear a diaper. Yes, and (2) the shape shown in FIG. 10D is preferable because the formation area of the leg periphery covering portions 24a and 24b can be minimized.

  In addition, the shape of a leg periphery coating | coated part is good also as a form which combined two or more said shapes. For example, the pants-type disposable diaper 1 shown in FIG. 1 has a shape that combines the shape of FIG. 10B and the shape of FIG. In other words, the inner diameters of the leg periphery covering portions 24a and 24b are formed so as to gradually narrow toward the leg periphery opening portions 12a and 12b from the crotch part 4 side toward the distal end side of the legs, and the leg periphery opening portions. 12a, 12b is an example in which the opening end on the outer thigh side is arranged at a higher position than the opening end on the thigh side, and the opening end on the outer thigh side is arranged at a position higher than the crotch part 4.

  Moreover, it is preferable that the leg periphery covering part is formed by extending the lower ends of the front body and the back body from the crotch part to 3 to 10 cm below at least on the inner thigh side. By setting it as 3 cm or more, the trouble of the brief type disposable diaper which a clearance gap produces in a leg periphery opening part by a wearer's operation | movement can be improved effectively. On the other hand, when the length is 10 cm or less, the leg-surrounding portion does not become unnecessarily long, so that attachment / detachment of the diaper is hindered, or the inner thigh side of the leg-surrounding portion is rubbed and less uncomfortable.

  Note that “at least the inner thigh side” is because the length of the inner thigh side close to the crotch part where side leakage is likely to occur is an important factor for the leakage prevention effect of the leg circumference covering portion. By doing so, it is possible to effectively improve the problem of the brief-type disposable diaper in which a gap is created in the opening around the leg by the wearer's movement.

[1-8] Solid gathering:
The pants-type disposable diaper of the present invention may have a three-dimensional gather in order to prevent side leakage of urine excreted by the wearer. The three-dimensional gather is a member for preventing side leakage of the urine excreted by the wearer, and is a leak-proof wall configured to stand up three-dimensionally. By forming such a three-dimensional gather, urine is excreted on the top sheet, and even if the urine spreads through the top sheet, the three-dimensional gather becomes a breakwater, and from the opening around the leg of the diaper, etc. Leakage (so-called “lateral leakage”) can be effectively prevented.

  The structure of a three-dimensional gather can employ | adopt the structure used for the conventional disposable diaper and other absorbent articles. For example, a stretchable material (a three-dimensional gathered stretchable material) disposed on a part of the water-repellent sheet material and a sheet (gather) formed on the sheet material by the three-dimensional gathered stretchable material can be suitably used. In the case of the pants-type disposable diaper according to the present invention, a configuration in which a three-dimensional gather is directly attached to the exterior member may be used. It is preferable to attach a gather.

[1-9] Various elastic materials:
In a pants-type disposable diaper, it is common to arrange an elastic material around the legs, arrange an elastic material around the waist, and more preferably arrange an elastic material around the abdomen.

  The leg circumference elastic material is an elastic material arranged along the leg circumference opening. By arranging the leg-stretchable material, a gather (leg gather) rich in stretchability can be formed in the leg-surrounding opening. Therefore, it is difficult to form a gap around the leg, and urine leakage from the opening around the leg can be effectively prevented.

  Only one leg elastic member may be arranged, or a plurality of leg elastic members may be arranged. When three or more leg elastic members are arranged, they may be arranged at equal intervals or at different intervals. Moreover, you may arrange | position so that the space | interval of several leg periphery elastic materials may change. For example, if the leg elastics are arranged so that the gap extends from the inner thigh side to the outer thigh side of the leg circumference covering part, and the leg elastics arranged in the upper stage are cut off to the outer thigh side, Since tension that pulls up toward the waist side acts on the inner thigh side of the covering portion, slipping of the diaper can be prevented.

  In addition, you may arrange | position an elastic material around a leg so that a number, arrangement | positioning, an expansion | extension state, etc. may differ in the front body and back body of a diaper. That is, the arrangement of the elastic material around the legs does not need to be a target in the front body and the back body, and may be asymmetric. For example, in the front body, it is preferable to arrange the stretchable material with a curve that is convex toward the waist so as not to hinder the movement of the legs. On the other hand, in the back body, it is preferable to increase the number of stretchable materials or to arrange the spacing between the stretchable materials relatively wide so as to securely wrap the buttocks. However, in order to obtain a uniform tightening force around the legs, it is preferable that the stretched state be the same.

  By the way, in the pants-type disposable diaper of the present invention, like the pants-type disposable diaper 1 shown in FIG. 1, the leg-surrounding elastic members 40 are disposed on the leg-surrounding covering portions 24 a and 24 b and are disposed so as to cross the crotch part 4. There is a feature that there is no. In this way, when the elastic material around the legs does not cross the crotch part, unnecessary width direction expansion / contraction force does not act on the diaper crotch part, and the crotch part does not entangle, so the feeling of wearing and fitting the diaper There is an advantage that it is excellent. On the other hand, in a conventional pant-type diaper such as the pant-type disposable diaper 100 shown in FIG. 3, the leg-around elastic material 40 is disposed so as to cross the crotch part 4, and unnecessary expansion and contraction in the crotch part of the diaper is unnecessary. Since the force acts, the crotch part may be twitched, and there is a possibility that the wearing feeling and fitting feeling of the diaper may be lowered. In such a case, there is a method in which the elastic material around the legs is cut at the crotch part and the elastic material is snapped back. However, a hole is formed in the exterior member at the time of cutting, or the elastic material that cannot be completely removed remains in the crotch part. There is a possibility that a new problem may occur.

  The waist elastic material is an elastic material arranged along the waist opening. By arranging the elastic material around the waist, a gather (waist gather) rich in elasticity can be formed in the waist opening. This waist gather makes it difficult for gaps to be formed around the waist, preventing urine leakage from around the waist, and improving the fit of the diaper to the wearer, thereby preventing the diaper from falling down.

  It is preferable that a plurality of waist elastic members are arranged, but only one may be arranged. When three or more waist elastic members are disposed, they may be disposed at equal intervals or at different intervals. Moreover, you may arrange | position so that the space | interval between several elastic materials around a waist may change. You may arrange elastic materials around the waist so that the number, arrangement, stretched state, etc. are different between the front and back of the diaper, but in order to obtain a uniform tightening force, the waist circumference It is preferable to arrange an elastic material.

  An abdominal circumference elastic material is an elastic material arrange | positioned in the part (namely, part equivalent to a wearer's abdominal circumference) between a waist circumference opening part and a leg circumference opening part. By arranging the elastic material around the abdomen, it is possible to form a gather (tammy gather) rich in elasticity around the abdomen of the wearer. This Tammy Gather, together with West Gather, can make the diaper fit and anti-slip effect even better.

  It is preferable that a plurality of belly stretchable materials are arranged, but only one may be arranged. When three or more belly stretchable materials are arranged, they may be arranged at equal intervals or at different intervals. Moreover, you may arrange | position so that the space | interval of several belly circumference elastic materials may change. For example, if the elastic material around the abdomen is placed so that the gap increases from the center of the diaper toward the side edge, tension is applied to the crotch or inner thigh of the diaper so that it can be lifted toward the waist. Slip-off can be prevented.

  You may arrange | position an elastic material around a stomach so that a number, arrangement | positioning, an expansion | extension state, etc. may differ by the front body side and back body side of a diaper. For example, in the front body that absorbs a lot of urine and easily slips down, it is preferable to increase the number of elastic materials, use an elastic material that is thick and has strong contracting force, or fix the elastic material in a highly stretched state. .

  In the pants-type disposable diaper 1 shown in FIGS. 1 and 2, a plurality of leg elastic members 40 are arranged on the periphery of the leg openings 12 a and 12 b, and the waist is provided on the periphery of the waist opening 10. A plurality of waist elastic members 42 are disposed so as to surround the opening 10, and further, a portion between the waist opening 10 and the leg openings 12 a and 12 b (ie, corresponding to the wearer's abdomen). Part) is an example in which a plurality of belly stretchable members 44 are arranged so as to surround the wearer's belly.

  As an elastic material, the elastic material which has been used with the conventional disposable diaper can be used conveniently. Specific examples include elastic rubber, elastic film, elastic foam (urethane foam, etc.), etc., as well as thread rubber and flat rubber made of elastic materials such as natural rubber and synthetic rubber (urethane rubber, etc.). .

  The stretchable material is preferably fixed in the stretched state in order to exert a sufficient stretch force. For example, when the elastic material is natural rubber or synthetic rubber, it is preferably fixed in a stretched state of 120 to 400%, and more preferably fixed in a stretched state of 200 to 300%. By fixing in the extended state in such a range, a sufficient stretching force can be applied, and the waist opening and leg opening can be prevented from being unnecessarily reduced.

[2] Method for producing a pants-type disposable diaper of the present invention:
Hereinafter, with respect to the manufacturing method of the pants-type disposable diaper of the present invention, refer to FIG. 8 (FIG. 8 (a) and FIG. (B)) as appropriate, according to an example of manufacturing the pants-type disposable diaper 1 shown in FIGS. While explaining. 8A and 8B are drawn in a form in which a part of the stretchable material around the legs, the stretchable material around the waist, the stretchable material around the abdomen, and the joint points are discarded for the convenience of drawing.

[2-1] Production of absorbent main body:
An absorber wrapped in a hydrophilic sheet is disposed on the upper surface of the back sheet, and a top sheet is further disposed on the upper surface. Subsequently, the absorptive main body 14 is obtained by sealing so that the peripheral part of an absorber may be pinched | interposed with a top sheet and a back sheet.

[2-2] Formation of front body continuum and back body continuum:
A plurality of long sheet materials are laminated, and a front body continuum and a back body continuum are formed in which a long stretch material is disposed between the sheet materials (FIG. 8B, process) A). In the case of the pants-type disposable diaper 1 shown in FIG. 1 and FIG. 2, the exterior member 16 is composed of two nonwoven fabrics, an inner sheet 16a and an outer sheet 16b. Prepare two each for the back and the back. A waist elastic member 42, an abdominal elastic member 44, and a leg elastic member 40 are disposed on the upper surface of one of the non-woven sheets (this sheet becomes an outer sheet) and bonded and fixed. Then, another non-woven sheet (this sheet becomes an inner sheet) is laminated and fixed on the upper surface, so that the waist elastic member 42 and the belly elastic member 44 are provided between the two non-woven sheets. In addition, the front body continuum 50 and the back body continuum 52 in which the leg elastic members 40 are interposed are obtained. The front body continuum is the front body sheet 30 in the diaper, and the back body continuum is the back body sheet 32 in the diaper.

  In the illustrated example, the front body continuum 50 and the back body continuum 52 are formed from separate sheet materials. However, the same sheet material has a portion corresponding to the front body continuum and the back body continuum. After forming the corresponding portions, the front body continuum and the back body continuum may be formed by cutting and separating these portions.

[2-3] Formation of diaper continuum:
Next, the front body continuum 50 and the back body continuum 52 are juxtaposed so that the side edges on the crotch lower side of the diaper are in contact with each other (FIG. 8B, step B), and at least one An absorbent main body 14 in which an absorbent body is interposed between a top sheet made of a liquid-permeable material and a back sheet made of a liquid-impermeable material. 52 are intermittently arranged and fixed in the longitudinal direction of these continuous bodies so as to straddle 52 (FIG. 8 (b), step C).

  At this time, the side edges of the diaper crotch side in the front body continuum 50 and the back body continuum 52 are the front body as shown in FIG. 8A (AA ′ cross-sectional view). The overlapping part 54 of the back continuous body 50 and the back body continuous body 52 is brought into contact with each other (the overlapping part 54 later becomes the leg periphery covering portions 24a and 24b). By doing so, the absorbent main body 14 is not placed on the overlapping portion 54, and the absorbent main body 14 can be prevented from obstructing the formation of the crotch joint 8c described later.

  Furthermore, the elongate pressing sheet 28 which consists of a nonwoven fabric is arrange | positioned so that the front end and rear end of the absorptive main body 14 may be coat | covered ((b) figure in FIG. 8, process D). After the front body continuum 50 and the back body continuum 52 that are arranged in parallel are folded so as to overlap each other (FIG. 8B, step E), the front body continuum 50 and the back body continuum 52 are aligned. In this example, the gap portion of the absorbent body 14 that is intermittently disposed and fixed is joined to form the outer thigh side joint portion 8a, and the crotch lower part of the diaper and the inner crotch side portion of the leg circumference covering portion are joined. The inner thigh side joint 8b and the crotch joint 8c are formed.

For example, in the pants-type disposable diaper 1 shown in FIG. 1, the outer thigh side joint 8a, the inner thigh side joint 8b, and the crotch joint 8c form a joint point 34 by heat sealing, and the outer thigh side joint 8a. By forming a line-shaped joint point 34a on the inner side and forming a dot-shaped joint point 34b for the inner leg side joint part 8b and the crotch joint part 8c, the outer leg side joint part 8a rather than the inner leg side joint part 8b. This is an example in which the bonding strength is high .

Further, the pants-type disposable diaper 120 shown in FIG. 7 also has a joint point 38 formed by heat sealing with the outer thigh side joint 8a, the inner thigh side joint 8b, and the crotch joint 8c, and the outer thigh side joint 8a. By forming a laterally V-shaped joint point 38a on the inner side and forming a dot-shaped joint point 38b for the inner leg side joint part 8b and the crotch joint part 8c, the outer leg side than the inner leg side joint part 8b is formed. This is an example in which the bonding strength of the bonding portion 8a is high . However, instead of heat sealing, bonding may be performed by ultrasonic fusion or adhesion using an adhesive.

  In the case where the peripheries of the joint points 34a and 38a of the outer thigh side joint portion 8a are configured to be long like the pants-type disposable diaper 1 shown in FIG. 1 or the pants-type disposable diaper 120 shown in FIG. What is necessary is just to make the convex shape used at the time of joining, the concave shape, and the embossing shape of an embossing roll differ by formation of a side joining part and an outer leg side joining part.

In addition, when joining the inner thigh side edge, outer thigh side edge and crotch lower end of the front body sheet and back body sheet by heat bonding or ultrasonic fusion, it is outside the inner thigh side edge. It is also preferable to perform joining by applying high energy to the thigh side edge portion to form the inner thigh side joint portion and the outer thigh side joint portion. By carrying out like this, a front body sheet and a back body sheet are joined firmly, and high joint strength can be obtained. For example, by making the joining temperature when forming the outer thigh side joint part lower than the joining temperature when forming the inner thigh side joint part and the crotch joint part , it is possible to make a difference in the joint strength of both joint parts. I can .

  In this example, the bonding temperature, i.e., a high temperature on the outer thigh side edge, that is, an example of bonding by applying high thermal energy, but by applying high pressure, Even at the same temperature and pressure, the same effect can be obtained by extending the joining time. Moreover, when adopting ultrasonic fusion as the bonding method, the same effect can be obtained by increasing the output of the ultrasonic wave. Furthermore, the same effect as that obtained by applying a high pressure can be obtained by reducing the clearance between the convex mold and the concave mold used at the time of joining.

  Thereafter, the leg opening portion and the outer side of the inner thigh side joint portion 8b and the crotch joint portion 8c are trimmed, and the trim pieces 56 and 58 are removed to form the diaper continuous body 60 (in FIG. 8). (B) Figure, step F).

  Finally, a plurality of pants-type disposable diapers 1 can be obtained by cutting along the outer thigh side joint portion 8a of the diaper continuous body 60 ((b) diagram in FIG. 8, step G).

  The pants-type disposable diaper of the present invention can be used as an absorbent article for infants or adults such as elderly people and disabled persons who need care.

It is a schematic perspective view which shows one Embodiment of the underpants type disposable diaper of this invention, and is the figure which shows the state which looked at the underpants type disposable diaper of this invention from the front. It is a schematic sectional drawing which shows one Embodiment of the underpants type disposable diaper of this invention, and is a figure which shows the A-A 'cross section of the underpants type disposable diaper shown in FIG. It is a schematic perspective view which shows one Embodiment of the conventional pants type disposable diaper, and is the figure which shows the state which looked at the conventional pants type disposable diaper from the front. It is process drawing which shows the method of measuring the joint strength of the junction part of the underpants type disposable diaper of this invention. It is a schematic diagram which shows the example of the form of the junction of the junction part of the underpants type disposable diaper of this invention. It is a schematic perspective view which shows another embodiment of the underpants type disposable diaper of this invention, and is the figure which shows the state which looked at the underpants type disposable diaper of this invention from the front. It is a schematic perspective view which shows another embodiment of the underpants type disposable diaper of this invention, and is the figure which shows the state which looked at the underpants type disposable diaper of this invention from the front. It is process drawing which shows one Embodiment of the manufacturing method of the underpants type disposable diaper of this invention. It is a schematic perspective view which shows another embodiment of the underpants type disposable diaper of this invention, and is the figure which shows the state which looked at the underpants type disposable diaper of this invention from the front. It is a schematic front view which shows embodiment of a pants-type disposable diaper , and is a figure which shows the shape of a crotch part and a leg periphery coating | coated part.

Explanation of symbols

1, 100, 110, 120, 130: pants-type disposable diaper, 2: front body, 4: crotch, 6: back body, 8: joint, 8a: outer thigh side joint, 8b: inner thigh side joint 8c: Crotch joint, 10: waist opening, 12, 12a, 12b: leg opening, 14: absorbent body, 16: exterior member, 16a: inner sheet, 16b: outer sheet, 18: top sheet , 20: Back sheet, 22: Absorber, 24, 24a, 24b: Leg circumference covering part, 28: Presser sheet, 30: Front body sheet, 32: Rear body sheet, 34, 34a, 34b, 36, 36a, 36b , 36c, 36d, 38, 38a, 38b, 46, 46a, 46b: joint point, 40: elastic material around the leg, 42: elastic material around the waist, 44: elastic material around the abdomen, 50: front body continuum, 52: rear Time continuum, 54: overlapping portions, 56, 58: trim piece, 60: diaper continuum, 70: pants-type disposable diaper, 72: outer thigh side test piece, 74: inner thigh side test piece, 76: chuck.

Claims (8)

Consists of each part of the front body, crotch and back body, equipped with an absorbent for excrement absorption,
The lower end of the sheet material (front body sheet) constituting the front body and the lower end of the sheet material (rear body sheet) constituting the rear body are extended downward from the crotch part,
By joining the inner thigh side edge, outer thigh side edge and crotch lower end of the front body sheet and the back body sheet, the inner thigh side joint, the outer thigh side joint, the crotch joint, One waist opening, a pair of leg openings and a leg covering are formed,
Each joint point of the inner thigh side joint part is formed in a dot shape, and the joint point of the outer thigh side joint part is formed in a line shape or a V shape,
A pants-type disposable diaper configured such that the joint strength of the outer thigh side joint is higher than that of the inner thigh side joint. The underpants-type disposable diaper according to claim 1, wherein the outer strength side joint portion is configured to have higher joint strength than the crotch joint portion. The inner thigh side joint and the outer thigh side joint are joined by at least one joining point,
The pants-type disposable diaper according to claim 1, wherein the perimeter of the joint point of the outer thigh side joint is longer than the perimeter of the joint point of the inner thigh side joint. Consists of each part of the front body, crotch and back body, equipped with an absorbent for excrement absorption,
The lower end of the sheet material (front body sheet) constituting the front body and the lower end of the sheet material (rear body sheet) constituting the rear body are extended downward from the crotch part,
By joining the inner thigh side edge, outer thigh side edge and crotch lower end of the front body sheet and the back body sheet, the inner thigh side joint, the outer thigh side joint, the crotch joint, One waist opening, a pair of leg openings and a leg covering are formed,
Each joint point of the inner thigh side joint part is formed in a line, and the joint point of the outer thigh side joint part is formed in a plurality of lines.
A pants-type disposable diaper configured such that the joint strength of the outer thigh side joint is higher than that of the inner thigh side joint. Each joint point of the crotch joint part is formed in a dot shape, each joint point of the crus side joint part is formed in a line, and the joint point of the crus joint part is in a plurality of lines. Formed,
5. The pants-type disposable according to claim 4, wherein the joint strength of the crus joint is higher than that of the crotch joint, and the joint strength of the crus joint is higher than that of the crus joint. Diapers. The front body sheet and the back body sheet are made of nonwoven fabric,
The pants-type disposable diaper according to any one of claims 1 to 5, wherein the outer thigh side edge is made of a non-woven fabric having a higher basis weight than the non-woven fabric constituting the inner thigh side edge. The pants-type disposable diaper according to any one of claims 1 to 6 , wherein the joint strength of the inner thigh side joint is 3.0 N / 25 mm to 20.0 N / 25 mm. The pants-type disposable diaper according to any one of claims 1 to 7 , wherein the joint strength of the outer thigh side joint is 7.0 N / 25 mm to 30.0 N / 25 mm.

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