FR2566631A1 - Nappy-pants with elastic waistband and method for manufacturing such nappy-pants - Google Patents

Abstract

Nappy-pants comprising first elastic means 7 fastened in the stretched state along two longitudinal edges 3 of the absorbent pad 1 and second elastic means 8 fastened in the stretched state on two waistband strips 11 which, before use, are joined by a tearable, longitudinal weakening line 10 to the remaining part of the nappy-pants.

Description

 Diaper with elastic waistband and method of manufacturing such a diaper.

 The subject of the present invention is a diaper, in particular for young children, comprising an absorbent cushion of generally substantially rectangular shape, a thin flexible sheet impermeable to moisture covering the underside of said cushion, said sheet having a width and a length greater than that of the cushion so as to exceed the latter laterally and longitudinally, a moisture-permeable veil covering the upper face of the cushion and of the sheet, elastic means fixed in the stretched state on said sheet, along the two opposite longitudinal edges of the cushion, and means for closing the diaper at the height of the wearer's waist.

 To allow continuous and high-speed production of diapers, it is essential that the elastic means which must be fixed in the stretched state be placed continuously parallel to the manufacturing direction, before the layers are separated. - panties from each other. This is generally how elastic means are laid along the two opposite longitudinal edges of the absorbent pads, with the aim of improving the seal in the crotch portion. located at the waist and this problem cannot be solved, without reducing the production rate, in the same way as that at the crotch part by the installation of elastic means stretched also along the two opposite transverse edges of the cushion, ie at the height of the belt portion. Indeed, an installation of elastic means stretched transversely to the manufacturing direction would imply an interruption of the advance and a discontinuous installation during the stop, hence a considerable reduction in the production rate.

The subject of the present invention is a diaper with improved tightness, comprising elastic means stretched both along the opposite longitudinal edges of the cushion and at the waist, to improve the tightness both in the crotch part. that at -cturing, this diaper can be manufactured continuously, at high speed. The invention also relates to a diaper that can be put on and closed quickly and easily. Finally, the subject of the invention is a
simple manufacturing process for improved waterproofing diapers by
the provision of elastic means along the opposite longitudinal edges of the
absorbent cushion and at the waist.

On the diaper according to the invention, the closure means of
the diaper up to the waist of the wearer include two strands of
belt which are formed by the waterproof sheet covered by the veil,
one end of each of said strands being integral with a longitudinal edge
of the sheet and the veil, at the level of a first end of the layer
panties, and means in the vicinity of the second end of the diaper
panties, for positioning and / or fixing the free part of the two
strands after passing around the flanks of the carrier, each of said strands ctm-
carrying an elastic means fixed on the strand in the longitudinal direction of the latter, in the stretched state.

During the manufacture and until the use of the diaper, both
belt strands are arranged in the longitudinal direction of the diaper
te, which allows dty to fix the elastic means in the stretched state in the direction
longitudinal of the diaper, so at the same rate as the means
elastic bands arranged along the longitudinal edges of the absorbent pad for
improve the tightness in the longitudinal part. The laying of means
elastic ensuring the elasticity of the belt strands, thus improving
the tightness on the belt, can thus be done at the same rate as the fitting
elastic means improving the seal in the crotch portion.

Preferably, the free part of each belt strand, before use
sation # of the diaper, is connected along its entire length by a line
tearable weakening at the remaining part of the diaper.

To strengthen the belt strands, it is advantageous that these strands
include an additional layer of waterproof sheet.

This additional layer of waterproof sheet can advantageously
be made up of the fact that the waterproof sheet has two flaps
opposite folded around two longitudinal fold lines, located at
outside the longitudinal edges of the absorbent pad and outside the
elastic means along the edges of the cushion, on the upper face of the
absorbent pad, as proposed in the French patent application
NO 84 00179 filed January 6, 1984. In this case, as proposed in this
on request, the free inner edges of these flaps can either be rectilinear over their entire length, so as to leave a window between them over the entire length of the diaper, or each have a median notch, so that the two flaps overlap in the area of the two ends of the diaper and leave a window between them only in an intermediate area.

If said flaps are provided, a bonding line or preferably a weld line is provided on either side of each weakening line separating the belt strands from the remaining part of the panty layer. These weld or bonding lines ensure the seal between the two layers of sheet of the diaper and the cohesion of the layers of the strands forming a belt.
The means for positioning and / or fixing the free part of the two belt strands in the vicinity of the second end of the panty layer may include, for example, slots for the passage of the free parts of the two strands, before said two parts are tied together, for example by knotting.

 According to a variant, the impermeable sheet comprises, in the vicinity of the second end, means for fixing by wedging the free parts of the belt strands. These means of fixing by wedging can be constituted for example by two plates of material more rigid than that of the impermeable sheet, having a cutout forming a tongue with an inclined flank so as to produce a self-pinching effect on the belt strand when the strand inserted under the tongue is stressed in tract ion.

The method of manufacturing diapers according to the invention consists in
- place absorbent cushions at intervals on a strip of flexible sheet, a waterproof one longer than that of the cushions, animated by a continuous advancement movement,
- lay and fix the first elastic elements in the stretched state on the sheet, along the two longitudinal edges of the absorbent cushions,
placing and fixing second elastic elements in the stretched state on the sheet, to said first elastic elements, externally along the two longitudinal edges of the strip,
- lay and fix a moisture permeable veil strip on the strip
sheet fitted with cushions and elastic elements,
- at intervals, in the sheet strip and the strip of
veil, longitudinal lines of weakness passing between the first
and the second elastic elements, on each side of the absorbent cushions and
- section the sheets and veil strips transversely between
the successive absorbent cushions, in line with one end of the lines
weakening.

Referring to the accompanying drawings, we will describe below in more
detail two illustrative and non-limiting embodiments of a
diaper according to the invention; on the drawing
Figure 1 is a plan view, partially broken away, of a first
embodiment of a diaper according to the invention;
Figure 2 shows a diaper according to Figure 1 in posi
tion of use;
Figure 3 is a plan view, partially broken away, of a second
embodiment of a diaper according to the invention;
Figure 4 is a partial view of the diaper of Figure 3 in
position of use, showing the fixing by jamming a strand of
belt.

The diaper illustrated in Figure 1 includes an absorbent pad
bant 1 of generally rectangular shape. The cushion 1 can be fixed in the usual way, for example by longitudinal lines of glue, not shown.
tees, on a flexible sheet 2, impermeable to moisture, of general shape
rectangular. Sheet 2 is longer and wider than the cushion
absorbent 1 which is placed centrally on the sheet 2 so
that the longitudinal edges 3 and the transverse edges 4 of the cushion 1 are
set back from the longitudinal edges 5 and the trans edges
versals 6 of sheet 2.

On each side of the absorbent pad 1, two elastic multi elements
strands 7 and 8 are fixed in the stretched state, in the longitudinal direction on the same
face of the sheet 2 as the cushion 1. The multi-strand elastic elements 7
are arranged closer to the longitudinal edges 3 of the cushion 1, on the part
median of the length of the longitudinal edges 5 of the sheet 2, e 'is to
say in a symmetrical position with respect to the two transverse edges 6.

The elastic elements 8 are arranged closer to the longitudinal edges 5 of the sheet 2, in an asymmetrical position relative to the two transverse edges 6 of the sheet 2, that is to say closer to one of the transverse ends than to the 'other. In the example shown, the elements 7 extend over a length somewhat less than the length of the absorbent pad 11 and the elements 8 extend substantially from the middle of the length of the sheet 2, over a length less than the half the length of the absorbent pad 1.

 The assembly constituted by the sheet 2, the absorbent pad 1 and the elastic elements 7 and 8 is covered, on the upper face, by a veil 9 permeable to moisture, fixed for example by gluing lines not shown in the sheet 2 and possibly the absorbent pad 1.

 On each side of the absorbent pad 1, the multilayer structure formed by the sheet 2 covered by the web 9 has a weakening line 10 formed for example by a line of slots or perforations, this weakening line 10 s' extending longitudinally from the end 6 of the sheet 2 away from the elastic elements 8 to a distance from the opposite end 6, passing between the elastic elements 7 and 8 located on the same side This line of weakness 10 therefore delimits, with the corresponding longitudinal edge 5 of the sheet 2, a longitudinal strip II, provided with a stretched longitudinal elastic element 8, this strip 11 being able to be torn off from the remaining part of the diaper along the line d weakening 10, except in the vicinity of an end 6 where there remains an unenforced part 12 by which the strip 11 is firmly and permanently connected to the remaining part of the diaper.

 In the vicinity of the opposite end 6 of the sheet 2, the multilayer structure formed by the sheet 2 and the web 9 comprises, at a distance inward relative to the weakening lines 10, two cutouts 13 in the form of openings longitudinal elongates having a length equal to or slightly greater than the width of the strips 11.

 Figure 2 shows the diaper according to Figure 1 in the use position, the strips 11 having been torn along the lines of weakness and the elastic elements being relaxed. One recognizes on each strip 11 a gathered area 14 formed the elastic element 8 relaxed, and on each longitudinal edge of the diaper, along the absorbent pad 1, a gathered area 15 formed by the elastic element 7 relaxed. To fix the diaper around the wearer, the bands 11 are passed in the form of belt strands from the back to the front around the flanks of the wearer and the free ends of the bands 11 are threaded from the inside towards outside and from back to front (in Figure 2) through the cutouts 13 located in the part of the diaper located on the front of the wearer, before tying the two strips 11 ' one to the other on the front of the wearer. The two bands 11 thus constitute an elastic belt for the diaper.

 In the diaper variant according to FIGS. 3 and 4, an absorbent cushion 101 of rectangular shape is placed in the middle position on an impermeable sheet 102 having a length slightly greater than the length of the cushion 101 so that the two transverse edges 103 of the cushion 101 are set back relative to the transverse edges 104 of the sheet 102. Perpendicular to the length of the cushion 101, the sheet 102 has a width greater than twice the width of the panty layer to be produced. The two lateral parts of the sheet 102 projecting from the longitudinal edges 105 of the absorbent pad 101 are folded up, along longitudinal fold lines 106 located at a distance outwardly from the longitudinal edges 105, in the form of a flap 107 on the top of the absorbent pad 101, so that the flaps 107 overlap each other at their free ends.

 Each flap 107 has, in its free (longitudinal) edge 108, in the middle of the length of said edge, over a length less than the length of the absorbent pad 101, a trapezoidal notch 109 of a depth such that the two flaps 107 which are cover each other by their ends on either side of the notches 109 provide between them an opening or window at the location of the notches 109 and that the bottom 110 of each notch 109 is located at a distance towards the inside with respect to the corresponding longitudinal edge 105 of the cushion 101. In other words, the window thus formed has a width and a length less than the width and the length of the cushion 101.

 On each flap 107 is fixed in the stretched state an elastic element 111 in the form of a ribbon extending lengthwise between the longitudinal edge 105 of the cushion 101 and the bottom 110 of the notch 109 of the flap 107.

The elastic element 111 is arranged symmetrically with respect to the two transverse edges 104 of the sheet 102 and has, in the example illustrated, a length substantially equal to the length of the bottom 110 of the zoidal trapezoidal notch 109.

 Between each longitudinal edge 105 of the absorbent pad 101 and the longitudinal edge of the sheet 102 corresponding to the fold line 106, another elastic element 112 in the form of a ribbon is fixed in the stretched state to the flap 107. The elastic element 112 extends substantially from the middle of the length of the sheet 102 to a distance from a transverse edge 104 of the sheet 102.

 X. 'assembly formed by the absorbent cushion 101 and the sheet 102, with the flaps 107 carrying the elastic elements 111 and 112 folded over the top of the cushion 101, is covered on the upper face by a veil 113 permeable to moisture.

 At 11 outside the longitudinal edges 105 of the absorbent pad 1015 the assembly formed by the two thicknesses of impermeable sheet 102 and the permeable veil 113 comprises, on each side of the absorbent pad 101, a longitudinal weakening line 114 flanked on both sides other of a weld line 115, 116. The line 114 originates at the longitudinal edge 106, at a distance from the transverse edge 104 distant from elastic element 112, and is understood dab ~ rd obliquely inward, then parallel to the edge 106 to a short distance from the opposite transverse edge 104, to thus define a tear-away strip 117 forming a strand of elastic belt, permanently connected by a part 118 which is not weakened to the remaining part of the panty layer.

 For the closure of the diaper around the wearer using the two belt strands 117, the diaper includes, near the end opposite to that where the strips 117 are integral (at 119) with the diaper, two attachment elements constituted by two plates 119 of a more rigid material than the sheet 102, fixed on the outside face of the sheet 102. Each plate 119 comprises a trapezoidal cutout giving rise to a tongue 120 having two sides converging in the direction of the connection zone of the tongue 120 with the plate 119.

 After tearing the strips 117 along the lines of weakness 114 and after fitting the diaper on the user, the strips 117 are passed in the form of two strands of belt from the rear to the front around flanks of the wearer and the free parts of the strands 117 are inserted below the tabs 120 of the pads 119. Any traction then exerted towards the fastening part 118 on a belt strand 117 causes the free part of the strand 117 by the "inside" side of the tongue 120 of the plate 119.

 To detach the belt strand 117 again, it suffices to pull the free end of the strand 117 downward on FIG. 4, that is to say in the direction of the free end of the tongue 120, to unlock the strand 117.

 It should be noted that the two embodiments described above and illustrated by the accompanying drawings have been given for information only and are not limitative and that numerous modifications and variants are possible within the framework of invention. Thus, the multi-strand elastic elements 7 and 8 of the embodiment of FIGS. 1 and 2 could be replaced by the elastic elements 111 and 112 in the form of a ribbon of the embodiment of FIG. 3, and vice versa. The straight lines of weakness 10 of the embodiment of FIGS. 1 and 2, starting from a transverse edge 6 of the diaper, could also be replaced by lines of weakness with oblique ends such as lines 114 of the mode of FIG. 3, and vice versa. Likewise, the positioning slots 13 of the embodiment of FIG. 1 could be replaced by fastening elements such as the plates 119 of the embodiment of FIGS. 3 and 4, and vice versa.

 Finally, it should be noted that the nature of the constituent elements of the diaper is not the subject of the present invention and that it is possible to use conventional materials for the manufacture of diapers, for example, cellulose of the "fluff" type, possibly surrounded by a nonwoven or paper envelope, for the absorbent pad 1, 101, to a plastic material such as polyethylene for the waterproof sheet 2, 102, to a hydrophobic nonwoven, for example polypropylene, for the web 9, 113 permeable to moisture.

Claims (8)

 1. Diaper, especially for young children, comprising an absorbent cushion (1, 101) of generally substantially rectangular shape, a thin sheet (2, 102) flexible, impermeable to moisture, covering the underside of said cushion , said sheet having a width and a length greater than those of the cushion so as to exceed the latter laterally and longitudinally, a veil (9, 113) permeable to moisture covering the upper face of the cushion and said sheet, elastic means (7 , 111) fixed in the stretched state on said sheet, along the two opposite long tudinal edges d3, 105) of the cushion, and means (11, 13; 117, 119) for closing the diaper at the height of the size of the wearer, characterized in that the means for closing the diaper up to the waist of the wearer comprises two belt strands (11, 117) which are formed by the waterproof sheet (2, 102) covered by the veil (9, 113), an extremity of ch none of said strands being integral with a longitudinal edge of the sheet and of the web, at the level of a first end (6, 104) of the layer-c. this # and of the means (13, 119) in the vicinity of the second end 6s 104) of the diaper, for positioning and / or fixing the free part of the two strands after passing around the flanks of the wearer, each of said strands comprising an elastic means (8, 112) fixed on the strand in the longitudinal direction of the latter, in the stretched state.  2 .. diaper according to claim 1, characterized in that the free part of each belt strand (11, 117), before use of the diaper, is connected over its entire length by a line daffaiw blissement ( 10, 114) tearable at the remaining part of the diaper  3 diaper according to claim 1 or 29 characterized in that the belt strands (11, 117) are formed of two layers of iBperseable sheet.  4 diaper according to claim 3, characterized in that said waterproof sheet (2, 102) has two side flaps (107) folded over the upper face of the absorbent pad (101), as the weakening lines (114) affect the two thicknesses of the movable waterproof sheet on the two sides of the cushion (101) and that a weld line (115, 116) is provided on either side of each weakening line (114).  5. Cou # che-culottes according to any one of the preceding claims, characterized in that the means for positioning the free part of the belt strands comprise slots (13) formed in the sheet (2) and the web ( 9) for the passage of the free parts of the strands.  6. Diaper according to any one of claims 1 to 4, characterized in that the means for positioning and fixing the free part of the belt strands comprise means (119) for fixing by wedging.  7. Diaper according to claim 6, characterized in that the means for fixing by wedging comprise plates (119) of more rigid material than that of the impermeable sheet (102), and having a cutout forming a tongue (120 ) with an inclined side so as to produce a self-pinching effect on a belt strand.  8. A method of manufacturing diapers according to any one of the preceding claims, characterized in that the absorbent cushions are deposited at intervals on a flexible sheet strip, impermeable to moisture, of width greater than that of cushions, animated by a continuous advancing movement, which one places and fixes first elastic elements in the stretched state on said sheet, along the two longitudinal edges of the absorbent cushions, which one places and fixes second elastic elements in the stretched state, exterior to said first elastic bands, along the two longitudinal edges of the strip, which a moisture-permeable veil is placed and fixed on the sheet strip provided with cushions and elastic elements, which - interval cleaning, in the sheet strip and the web of veil, of the longitudinal weakening lines passing between the first and second elastic elements, on each side of the absorbent cushions, and quton sections the b sheet and veil andes transversely between the successive absorbent cushions, in line with one end of the lines of weakness.