JP4646013B2 - Disposable diapers - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a disposable diaper.
[0002]
[Prior art]
The disposable diaper disclosed in U.S. Pat. No. 4,695,278 is of an open type, and includes barrier cuffs having a tendency to stand up from the skin contact surface on both sides of the diaper. The barrier cuff is, for example, a belt made of woven fabric or non-woven fabric, and has a proximal edge and a distal edge that are parallel to each other, and the proximal edge is joined to a surface sheet that forms a skin contact surface of the diaper. The elastic member is attached to the distal edge in an extended state, and the distal edge tends to stand up from the skin contact surface by the contracting action of the elastic member. When the diaper is worn, the elastic member contracts, resulting in a number of pleats in the nonwoven fabric forming the distal edge.
[0003]
[Problems to be solved by the invention]
In the conventional diaper, the distal edge of the barrier cuff fits around the leg of the diaper wearer to prevent fluid leakage along the leg circumference. However, since there are many folds at the distal edge, it is difficult to avoid body fluid leaking from the gap between the folds and the skin with a barrier cuff fitted around the legs.
[0004]
The present invention relates to an improvement of a conventional diaper having a barrier cuff, and has an object to prevent body fluid from leaking between the barrier cuff and the skin.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the present invention is intended to have a skin contact surface and a clothing contact surface, and the skin contact surface is a front waistline region, a back waistline region, and both these regions in the length direction. It is a disposable diaper which consists of a crotch region located in between, and a barrier cuff having a standing tendency from the skin contact surface is formed on both sides extending in the length direction of the skin contact surface.
[0006]
In this disposable diaper, the present invention is characterized as follows. The barrier cuff comprises a strip-shaped sheet piece extending in the length direction. The strip-shaped sheet piece is joined to the skin contact surface and extends in the length direction, a free edge portion having a standing tendency from the skin contact surface and parallel to the base edge portion, and the front and rear And a front and rear end edge joined to the skin contact surface in the waist area. The sheet piece includes a sheet-like fiber assembly made of elastically extensible fibers. By the expansion and contraction of the elastically extensible fiber, the free edge portion can be elastically expanded and contracted in the length direction, but at the base edge portion, the elastically extensible fiber is contracted. And thus the base edge is substantially non-stretchable. In the sheet piece, the base edge portion and the front and rear ends in a state where the free edge portion is elastically extended in the length direction and the base edge portion is not substantially extended in the length direction. An edge is joined to the skin contact surface. Further, the sheet piece is formed by superimposing a sheet-like fiber aggregate made of elastically extensible fibers and a sheet-like fiber aggregate made of inelastically extensible fibers, and the sheet The sheet-like fiber assembly made of the elastically extensible fiber is elastically extended by being stretched in the length direction of the piece, and the sheet-like fiber assembly made of the inelastically extensible fiber. The body is stretched inelastically. Here, when the elastically extensible fibers are bonded to other fibers, the base edge portion of the sheet piece relaxes or disappears its elastic stress, and the base edge portion and the front and rear end portions Is bonded to the skin contact surface.
[0007]
The present invention has the following preferred embodiments.
(1) The contraction force with respect to the length direction of each part in the width direction of the barrier cuff gradually increases from the base edge portion toward the top of the free edge portion.
(2) The sheet piece is folded along a center line that bisects the width thereof, and is joined to the skin contact surface so that the center line is located at the free edge.
(3) The sheet piece is formed by superimposing a sheet-like fiber aggregate made of elastically extensible fibers and a sheet-like fiber aggregate made of inelastically extensible fibers.
(4) The sheet piece is obtained by superimposing the sheet-like fiber aggregate made of the inelastically extensible fibers on both surfaces of the sheet-like fiber aggregate made of the elastically extensible fibers. .
(5) The sheet piece is obtained by superimposing the sheet-like fiber aggregate made of the elastically extensible fiber on both surfaces of the sheet-like fiber aggregate made of the inelastically extensible fiber. .
[0008]
DETAILED DESCRIPTION OF THE INVENTION
The details of the disposable diaper according to the present invention will be described with reference to the accompanying drawings.
[0009]
1 and 2 are a partially broken perspective view of the disposable diaper 1 in a free state and a partially broken plan view of the diaper 1 in a flatly extended state. The diaper 1 is of an open type, and a liquid-permeable surface sheet 2 that forms a contact surface with respect to the skin of the wearer of the diaper 1 and a non-forming surface that forms a contact surface with respect to the wearer's clothes. It has a liquid-permeable back sheet 3 and a body fluid-absorbing core 4 interposed between both sheets 2, 3. The front and back sheets 2, 3 extend from the periphery of the core 4 and overlap each other to join each other. End edge flaps 11 and 12 and side edge flaps 13 are formed. The diaper 1 has a front waistline region 6, a back waistline region 7, and a crotch region 8 positioned between both regions 6 and 7 in the length direction (vertical direction in the figure). A tape fastener 14 is attached to the side edge flap 13 in the surrounding area 7. In the front and rear end edge flaps 11 and 12 and the side edge flap 13 in the crotch region 8, the waist elastic members 15 and 16 and the leg elastic members 17 extend on at least one inner surface of the front and back sheets 2 and 3. It is attached in a state. Barrier cuffs 18 that extend in the length direction of the diaper 1 around the crotch region 8 are attached to the top sheet 2 on both sides of the diaper 1.
[0010]
The barrier cuff 18 has a free edge portion 21, a base edge portion 22, front and rear end edge portions 23, 24, and is formed of a strip-shaped sheet piece in which an inner layer 20a and an exterior 20b are laminated. The base edge portion 22 and the front and rear end edge portions 23 and 24 are not bonded to the sheet 2 but are bonded to the topsheet 2 via the adhesive 26. In such a barrier cuff 18, the free edge portion 21 that occupies the width W ₁ in the entire width W and is located inward of the diaper 1 is formed to be elastically stretchable in the length direction of the diaper 1. A base edge portion 22 that occupies a width W ₂ indicated by hatching and is located outward of the diaper 1 is formed non-extensible in the length direction of the diaper 1. In the diaper 1 in the state of FIG. 2, the barrier cuff 18 is joined to the front and rear end edge flaps 11 and 12 of the diaper 1 with the front and rear end edges 23 and 24 in a state where the free edge 21 is extended in the length direction. ing. The base edge portion 22 has a length that reaches the front and rear end edge flaps 11 and 12 with the crotch region 8 as the center, and the entire length thereof is joined to the topsheet 2. When such a diaper 1 is in a free state and / or in a worn state, the free edge 21 of the barrier cuff 18 contracts in the length direction of the cuff 18, and the contracting action causes the surface as shown in FIG. A tendency to stand upward from the sheet 2 is shown.
[0011]
FIG. 3 is a sectional view taken along line III-III in FIG. The barrier cuff 18 in which the free edge portion 21 stands up forms a pocket 29 that opens toward the inside of the diaper 1 between the top sheet 2 and the barrier cuff 18. In the barrier cuff 18, the top portion 27 of the free edge portion 21 and the vicinity thereof elastically fit around the leg of the diaper 1 wearer, and body fluid is prevented from leaking from the side of the diaper 1. The inner layer 20a forming the barrier cuff 18 can be elastically extended in the length direction of the diaper 1 and imparts elastic extensibility to the free edge 21, and the outer layer 20b is formed of the diaper 1. The barrier cuff 18 can be stretched inelastically in the length direction and has a cloth-like touch on the outer surface of the barrier cuff 18.
[0012]
FIG. 4 is a diagram illustrating a process in which the barrier cuff 18 is formed on the diaper 1. In FIG. 4, a strip-shaped material sheet 41 to be the barrier cuff 18 is formed by laminating an elastic sheet 42 that can be elastically stretched and a non-elastic sheet 43 that can be stretched inelastically. 43 are joined intermittently in the longitudinal direction of the material sheet 41 indicated by arrows A and B by adhesion or welding. The elastic sheet 42 is a sheet-like fiber assembly such as a nonwoven fabric made of elastic yarn formed of an elastic material such as a styrene-based elastomer, or a film formed of an elastic material, and is elastic in the longitudinal direction of the material sheet 41. It is extensible. The melt blown nonwoven fabric having a basis weight of 10 to 50 g / m ² and made of continuous fibers of 5 to 25 dtex obtained by extruding a styrene elastomer with a melt blown extruder is an example of the material sheet 41. The non-elastic sheet 43 is a sheet-like fiber assembly such as a nonwoven fabric made of continuous fibers formed of an inelastic material such as polypropylene. When the non-elastic sheet 43 is extended in the length direction of the material sheet 41, the continuous fibers are extended. The extension remains as a permanent deformation. A meltblown nonwoven fabric having a basis weight of 5 to 50 g / m ² and made of continuous fibers of 5 to 25 dtex obtained by extruding polypropylene with a meltblown extruder is an example of the non-elastic sheet 43.
[0013]
The material sheet 41 formed in this way has a breaking elongation of the elastic sheet 42 and the non-elastic sheet 43 in the length direction in Step I, that is, the directions of the arrows A and B, and the elasticity of the elastic sheet 42. Within the limit, the first intermediate sheet 44 is preferably stretched in a range of stretch rate of 50 to 400%. In the first intermediate sheet 44, the elastic sheet 42 is in an elastically extended state, and the non-elastic sheet 43 is inelastically extended and permanently deformed. The first intermediate sheet 44 can be contracted in the direction opposite to the arrows A and B by the action of the elastic sheet 42.
[0014]
In Step II, one side edge of the first intermediate sheet 44 in the stretched state is heated and pressurized. By doing so, the stress of the elastic yarn of the elastic sheet 42 under elastic deformation is relaxed at the side edge portion, or the side edge indicated by the oblique line in which the elastic yarn is melted to eliminate the elastic contraction force A second intermediate sheet 47 having the portion 46 can be obtained. In the length direction of the second intermediate sheet 47, the side edge portion 46 is not contracted and the dimensions are fixed, but the portion 49 other than the side edge portion 46 can be contracted in the length direction of the sheet 47. It is.
[0015]
Step III is a drawing showing a state of the second intermediate sheet 47 when the elongation in the directions of arrows A and B is released. In the second intermediate sheet 47, the side edge portion 46 maintains its size without contracting, but the other portion 49 contracts in the direction opposite to the arrows A and B.
[0016]
In Step IV, the side edge portion 46 and both edge portions 51 and 52 of the sheet 47 are bonded to the upper surfaces of the side portions of the topsheet 2 while maintaining the extended state of the second intermediate sheet 47 obtained in Step II. It joins via the agent 26 (refer FIG. 3). At each side portion of the top sheet 2, the second intermediate sheet 47 is joined so that the side edge 46 is located outward of the top sheet 2.
[0017]
In the process V, the top sheet 2 that has undergone the process IV is overlapped with the back sheet 3 to sandwich the core 4, and the sheets 2 and 3 are bonded or welded to each other at the overlapping portions to obtain the diaper 1 shown in FIGS. . The core 4 is bonded to the top sheet 2 and / or the back sheet 3 as necessary. In the diaper 1 obtained in the process V, the second intermediate sheet 47 becomes the barrier cuff 18 of the diaper 1 of FIGS. The elastic sheet 42 and the non-elastic sheet 43 of the second intermediate sheet 47 become the inner layer sheet 20a and the outer layer sheet 20b of the barrier cuff 18, the side edge 46 becomes the base edge 22 of the barrier cuff 18, and both end edges 51, Reference numeral 52 denotes front and rear end edges 23 and 24 of the barrier cuff 18, and a portion of the second intermediate sheet 47 that is not joined to the topsheet 2 becomes the free edge 21 of the barrier cuff 18.
[0018]
In such a diaper 1, the material sheet 41 forming the barrier cuff 18 is elastically stretchable, and the sheet 41 is attached to the top sheet 2 as the second intermediate sheet 47 in the stretched state. Even when it 18 contracts, there is no fear that when it contracts like a barrier cuff of the prior art, a large number of pleats are generated and body fluid leaks from the gap between the folds and the skin around the legs. In the second intermediate sheet 47, the side edge 46 is non-extensible and has a length that reaches the front and rear end edges 11 and 12 of the surface sheet 2, so that the side edge 46 does not extend. It is possible to join the sheet 2 and the work for joining is easy. When the side edge of the first intermediate sheet 44 is heated and pressurized in Step II and the side edge is heated widely, the contraction force in the vicinity of the side edge 46 is weakened in the second intermediate sheet 47. As a result, the contraction force in the length direction of each part in the width direction of the barrier cuff 18 changes so as to gradually increase from the base edge portion 22 toward the top portion 27 of the free edge portion 21. Such a second intermediate sheet 47 is more easily attached to the top sheet 2. In the raw material sheet 41, the fibers used for the elastic sheet 42 and the non-elastic sheet 43 are preferably continuous fibers. Such a fiber is not deformed so as to form a loop between the portions where the sheets 42 and 43 are joined together when the barrier cuff 18 contracts, so that no pleats are generated in the barrier cuff 18. Even if the barrier cuff 18 repeats expansion and contraction, it does not fall off the barrier cuff 18 like a short fiber. The elastic sheet 42 may be a film instead of a sheet-like fiber assembly, but it goes without saying that no pleats are produced when the film shrinks. The elastic sheet 42 and / or the non-elastic sheet 43 is preferably water-impermeable and water-impermeable. Since the non-elastic sheet 43 is a fiber assembly, if the barrier cuff 18 is formed so that the non-elastic sheet 43 contacts the skin, the touch of the cuff 18 becomes cloth-like.
[0019]
FIG. 5 is a drawing similar to FIG. 3 showing an example of the embodiment of the present invention. The strip-shaped sheet piece forming the barrier cuff 18 in the diaper 1 is composed of an inner layer 20a and an outer layer 20b, but the two-layer sheet piece is folded along a center line 25 that divides the width into approximately two equal parts. It has been. The center line 25 forms the top part 27 in the free edge part 21, and the arc is formed by bending the strip-shaped sheet piece, and it is possible to make a flexible contact with the circumference of the leg of the diaper 1 wearer. .
[0020]
FIG. 6 is also a drawing similar to FIG. 3 showing an example of the embodiment of the present invention. In the barrier cuff 18 in the diaper 1, an outer layer 20 b that can be stretched inelastically is bonded to both surfaces of the inner layer 20 a having elastic stretchability. The inner layer 20a is in a state of being extended in the length direction of the diaper 1, and the barrier cuff 18 can be contracted in the length direction. In the diaper 1 according to the present invention, the barrier cuff 18 may be different from that shown in FIG. 6 in that the inner layer 20a is superimposed on both surfaces of the outer layer 20b.
[0021]
In this invention, in order to join the members forming the diaper 1, an adhesive such as a hot melt adhesive can be used, and when the members are made of a thermoplastic synthetic resin, the members are welded together. You can also In addition to being implemented with the open diaper 1 as shown in the drawings, the present invention may also be implemented with a diaper formed into a pants shape by joining the side edges of the front and rear waist regions 6, 7 together. Is possible. Unlike the illustrated example, the barrier cuff 18 may be formed such that the base edge portion 22 is located inside the diaper 1 and the free edge portion 21 is located outside the diaper 1.
[0022]
【The invention's effect】
In the disposable diaper according to the present invention, since the barrier cuff is formed by stretching a sheet material having elastic extensibility, when the diaper is worn, no gather is generated in the barrier cuff. The problem of the prior art that body fluid leaks from the gap between the skin around the legs can be solved.
[Brief description of the drawings]
FIG. 1 is a partially broken perspective view of a disposable diaper.
FIG. 2 is a partially broken plan view of a disposable diaper in an extended state.
FIG. 3 is a diagram showing a cross section taken along line III-III in FIG.
FIG. 4 is a diagram showing a process of forming a barrier cuff.
FIG. 5 is a drawing similar to FIG. 3 showing an example of the embodiment.
6 is a drawing similar to FIG. 3 showing another example of the embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Disposable diaper 2 Top sheet 6 Front waist area 7 Rear waist area 8 Inseam area 18 Barrier cuff 21 Free edge part 22 Base edge part 23 End part (front end part)
24 end (rear end)
27 Top

Claims (6)

A skin contact surface and a clothing contact surface, wherein the skin contact surface comprises a front waistline region, a back waistline region, and a crotch region positioned between these regions in the length direction of the skin contact surface. Barrier cuffs having a standing tendency from the skin contact surface are formed on both sides extending in the length direction ,
The barrier cuff is composed of a strip-shaped sheet piece extending in the length direction, and the sheet piece is bonded to the skin contact surface and has a base edge portion extending in the length direction and an upright direction from the skin contact surface. A sheet having a free edge parallel to the base edge and a front and rear end edge joined to the skin contact surface in the front and rear waist area, wherein the sheet piece is made of elastically extensible fibers. In a disposable diaper comprising a fiber-like fiber assembly, wherein the free edge portion can be elastically expanded and contracted in the length direction by expansion and contraction of the elastically extensible fiber ,
The base edge portion is substantially non-stretchable by the shrinkage of the elastically extensible fibers at the base edge portion, and the free edge portion elastically extends in the length direction. The base edge and the front and rear end edges are joined to the skin contact surface in a state where the base edge is not substantially extended in the length direction ,
The sheet piece is formed by superposition of a sheet-like fiber assembly made of elastically extensible fibers and a sheet-like fiber assembly made of inelastically extensible fibers, and the length of the sheet piece The sheet-like fiber assembly made of elastically extensible fibers is elastically stretched by stretching in the direction, and the sheet-like fiber assembly made of inelastically extensible fibers is inelastic. Stretched,
When the elastically extensible fibers in the base edge of the sheet piece are bonded to other fibers, the base edge is relieved or eliminated its elastic stress,
The disposable diaper, wherein the base edge portion and the front and rear end portions are joined to the skin contact surface .   The disposable diaper according to claim 1, wherein the contraction force in the length direction of each part in the width direction of the barrier cuff gradually increases from the base edge toward the top of the free edge.   The said sheet piece is folded along the centerline which divides the width | variety into two substantially equally, and it joins to the said skin contact surface so that the said centerline may be located in the said free edge. Disposable diapers. Of claim 1 wherein the sheet piece is one that was the elastically superimposed sheet-like fiber aggregate made of stretchable fiber and the inelastically consisting extensibility of the fiber sheet-like fiber aggregate The disposable diaper described in any one.   5. The sheet piece is obtained by superimposing the sheet-like fiber aggregate made of the inelastically extensible fibers on both surfaces of the sheet-like fiber aggregate made of the elastically extensible fibers. Disposable diapers described in 1.   5. The sheet piece is obtained by superimposing the sheet-like fiber aggregate made of elastically extensible fibers on both surfaces of the sheet-like fiber aggregate made of inelastically extensible fibers. Disposable diapers described in 1.

Images