WO1994005240A1

WO1994005240A1 - Disposable absorbing diaper with improved tightness

Info

Publication number: WO1994005240A1
Application number: PCT/FR1993/000830
Authority: WO
Inventors: Philippe Vandemoortele; André Leroy
Original assignee: Peaudouce S.A.
Priority date: 1992-09-04
Filing date: 1993-08-26
Publication date: 1994-03-17
Also published as: NO950828L; AU4964793A; NZ248443A; NO950828D0; GB9317630D0; FR2695314A1; FR2695314B1; PL307785A1; CZ56195A3; HUT71826A; TNSN93096A1; EP0768852A1; ZA936103B; HU9500629D0; SK28695A3; GB2270247A; FI951000A; MX9305392A; JPH08501000A; CA2143854A1

Abstract

Disposable absorbant diaper comprising an external impervious support sheet (1), an absorbent pad (2) fixed to said support sheet, an internal pervious cover sheet (3) covering the absorbent pad, attaching means (9) to close the diaper, longitudinal elastic elements (8) fixed in a stretched condition to the support sheet outside the absorbent pad, and two side flaps (10) extending above the absorbent pad so that their proximal edges (13) are connected to said cover sheet along longitudinal lines situated inwards with respect to the longitudinal edges of the absorbent pad and so that their distal elastic edges (14) are situated close to each other. Said side flaps (10) are interconnected at their distal edges (14) from the transversal edges of the diaper at least up to the corresponding transversal edges of the absorbent pad (2), thus forming a peripheral fluid-tight barrier throughout the periphery of the absorbent pad.

Description

Disposable absorbent diaper with improved waterproofing.

The present invention relates to a hygiene article consisting of a disposable absorbent diaper intended for young children or incontinence, of the type comprising an absorbent pad disposed between an outer sheet of waterproof support and an inner permeable sheet.

Hygiene articles of this type are known, for example, from patent application GB-A-2,161,059 (Kimberly-Clark). According to this document, two lateral sealing flaps extend, above the absorbent pad, directed towards each other so that their elasticized distal edges are located close to each other. The two lateral sealing flaps are produced by a double folding of the liquid-permeable inner sheet covering the liquid-impermeable support sheet as well as the absorbent pad fixed on this support sheet. At their two ends corresponding to the two transverse edges of the diaper, the flaps are fixed so as to always be turned inwards, towards one another, without being able to fold outwards, for example during the implementation of the hygiene article on the user. These side flaps improve the sealing of the hygiene articles in the lateral direction, in particular in the crotch area. On the other hand, risks of leakage remain in the two belt areas.

It is also known, for example by patent application GB-A-2 159 693 (Kimberly-Clark), to provide in each belt zone of such a hygiene article, a pocket constituted by a flap s' extending from a transverse edge of the hygiene article towards the opposite transverse edge, the distal edge of this flap possibly being elasticated. These pockets improve sealing only in the belt areas.

It has also already been proposed to improve, on the same hygiene article, both the lateral tightness, in particular in the crotch area, and the tightness in the two belt areas. Thus, according to US Pat. No. 4,662,877 (Williams), the inner sheet of such a hygiene article is covered with an additional sheet, comprising, above the absorbent pad, a rectangular opening or cut, the two longitudinal edges of which are elasticized. It should be noted that according to this document, the additional sheet is fixed to the permeable inner sheet along two opposite transverse edges corresponding to the transverse edges of the hygiene article and along two opposite longitudinal edges situated outside the elastic elements d 'crotch of the hygiene article, which elastic elements are themselves located outside of the opposite longitudinal edges of the absorbent pad. Such an additional sheet comprising a rectangular opening with elasticated longitudinal edges is not entirely satisfactory, in particular because of the width of this opening (of the order of 12 cm for a length of the order of 30 cm). In addition, because of the width of the opening of the additional sheet, this sheet must itself be wider than the absorbent pad to provide two side flaps of sufficient width, which results in a significant consumption of material for this sheet. additional. However, in the case of disposable absorbent hygiene articles such as diapers, it is essential to reduce as much as possible the quantities of materials used, and therefore the cost price of the articles.

It has also already been proposed, for example by patent application EP-A-0 -376 022 (The Procter and Gamble), to provide an absorbent diaper with both two lateral sealing flaps and two belt pockets. However, the belt pockets are, in this document, produced by two added transverse bands, which complicates the manufacture of diapers, in particular when the latter are produced continuously in the longitudinal direction.

The object of the present invention is to produce a disposable absorbent diaper which, while being of simple structure and manufacture, internally comprises an effective sealing barrier extending over the entire periphery of the absorbent pad. .

The disposable absorbent diaper according to the invention comprises an outer support sheet of generally rectangular shape, impermeable to liquids, an absorbent pad of general shape rectangular, fixed on said support sheet and a permeable inner cover sheet covering the absorbent pad. The diaper further comprises fastening means to allow it to be closed around the waist of a user. The diaper further comprises longitudinal elastic elements fixed in the stretched state to the support sheet, outside the longitudinal edges of the absorbent pad. Two side flaps are located above the cover sheet and further extend above the absorbent pad so that their proximal edges are connected to said interior cover sheet along longitudinal lines located substantially above the edges. longitudinal of the absorbent pad or recessed inwardly relative to said edges and that their elasticized distal edges are located close to each other. According to the invention, said lateral flaps are interconnected at their distal edges from the transverse edges of the diaper at least to the corresponding transverse edges of the absorbent pad, thus forming a peripheral sealing barrier around the entire periphery of the absorbent cushion.

The two lateral sealing flaps can for example each consist of a section of tabular sheath fixed in the flattened state on the cover sheet of the diaper along a longitudinal line formed by the proximal edge of the flap and along the two transverse edges of the diaper, at least one elastic element being fixed in the stretched state in said sheath along a longitudinal line constituting the distal edge of the flap.

To further improve the lifting of the flaps relative to the absorbent cushion, a second elastic element can be fixed, in the stretched state, in said sheath section, along a longitudinal line located near the proximal edge of the flap. According to another embodiment, the lateral sealing flaps consist of the same section of tape covering the cover sheet over the entire length of the diaper and on the middle part of the width of the diaper being attached to the cover sheet along its two transverse edges corresponding to the transverse edges of the diaper and along of its two longitudinal edges constituting the proximal edges of the two flaps. This section of ribbon has, over a central part of its length, a longitudinal central slit, the two edges of which are elasticized by longitudinal elastic elements stretched to constitute the distal edges of the two lateral sealing flaps.

According to a variant, the two lateral sealing flaps are constituted by the cover sheet itself having, over a median part of its length, a longitudinal slot whose two longitudinal edges are elasticized by elastic elements fixed to the being tense. In this case, a section of tape of width at least substantially equal to the width of the absorbent cushion is disposed between the cover sheet and the cushion, over the entire length of the diaper, in the middle part of the width of that -this.

The longitudinal slot made either in the section of ribbon covering the cover sheet, or in the cover sheet itself, can advantageously be extended, at its two ends, by two transverse slots so as to delimit two flaps which, folded, define two sheaths in which said stretched longitudinal elastic elements are fixed ensuring the elasticity of the distal edges of the two lateral sealing flaps.

In the case where the longitudinal elastic elements ensuring the elasticity of the distal edges of the lateral sealing flaps are fixed inside sheaths, it may be advantageous to fix them only at their ends to said sheaths so that the elastic elements can , between these ends, slide in said sheaths.

Referring to the appended schematic drawings, several more illustrative and non-limiting embodiments of diapers according to the invention will be described below in more detail. In the drawings: FIG. 1 is a plan view of the interior face of a panty layer partially cut away according to a first embodiment of the invention; Figure 2 is a section on a larger scale along II-II of Figure 1; Figure 3 is a section on a larger scale along ϋl-III of Figure 1; Figure 4 is a plan view of the inner face of a diaper partially broken away according to another embodiment of the invention; Figure 5 is a section on a larger scale along VV of Figure 4; Figure 6 is a plan view of the inner face of a diaper partially broken away according to another embodiment of the invention; Figure 7 is a section, on a larger scale, along VII-VII of Figure 6; Figure 8 is a plan view of the inner face of a diaper partially broken away according to another embodiment of the invention; Figure 9 is a section on a larger scale along IX-IX of Figure 8; Figure 10 is a plan view of the inner face of a diaper partially cut away according to yet another embodiment of the invention; FIG. 11 is a section on a larger scale along XI-XI of FIG. 10.

The diaper as illustrated in FIGS. 1 to 3 comprises, in a manner known per se, a support sheet 1 impermeable to liquids, an absorbent pad 2, for example in cellulose fluff paste, optionally with incorporation of polymeric material said super absorbent, a cover sheet 3 permeable to liquids, for example in non-woven veil. The two sheets 1 and 3 have the same size and the same hourglass shape, that is to say a rectangular shape with two opposite side notches 4 delimiting, in the direction of the length of the diaper, a zone 5 crotch of reduced width between two end zones 6 and 7 of increased width.

The absorbent pad 2 disposed between the two sheets 1 and 3 also has an hourglass shape, but of more dimensions weak than the two sheets 1 and 3 which are interconnected for example by bonding around the entire periphery of the cushion 2.

Longitudinal elastic elements 8 each consisting for example of one or more elastic strands or threads or of an elastic strip are fixed in the stretched state to the support sheet 1, at least in the crotch region 5, between the bottom of the notches 4 of the sheet 1 and the bottom of the corresponding notches of the absorbent pad 2.

Furthermore, adhesive fasteners 9 are fixed to the opposite lateral edges of the end zone 6 constituting the rear part of the diaper.

Two lateral sealing flaps 10 are fixed on the cover sheet 3, above the absorbent pad 2, over the entire length of the diaper. The diaper as described above is of conventional structure and this is the reason why we have not shown, in order not to overload the drawings, the means of assembly, in particular by gluing, of these different various components.

Each flap 10 is constituted by a section of sheath 11 of a material permeable to air, for example a nonwoven preferably hydrophobic or impermeable to liquids, formed of a section of ribbon 11 folded and closed on itself by a longitudinal line 12 of bonding or welding. The sheath section 11 is fixed to the sheet 3 by a longitudinal line 13 of bonding or welding which extends over the entire length of the diaper in a position slightly recessed inwards relative to the edge of the cushion. absorbent 2 in the crotch area 5 (see Figure 2).

Each sheath section 11 thus fixed to the cover sheet 3 is disposed in the flattened state on the cover sheet 3 so as to extend, from the proximal edge defined by the fixing line 13, inwards at less substantially to the middle of the width of the absorbent pad 2, so that the distal edges 14 of the two opposite flaps 10 touch or are very close to each other.

A first longitudinal elastic element 15 is disposed in the stretched state inside the sheath section 11 of each flap 10, at near the distal edge 14 of the latter, and a second elastic longitudinal element 16 is disposed in the stretched state in the sheath section 11, in the vicinity of the proximal edge 13. It should be noted that each of the two longitudinal elastic elements 15, 16 extends over the entire length of the flap 10, therefore over the entire length of the diaper and is fixed to the sheath section 1 1 only at the two longitudinal ends while being free to slide between said two ends.

The sheath section 11 of each flap 10 is moreover fixed to the cover sheet 3, in the flattened state, at the location of the opposite transverse edges of the diaper, by gluing lines 17 visible in the figure. 3.

Finally, the two opposite flaps 10 are connected together, at their distal edges 14, from the two opposite transverse edges of the diaper to beyond the two corresponding opposite transverse edges of the absorbent pad 2, by fixing zones 18 , for example by gluing, visible in Figures 1 and 3.

When the diaper thus formed is worn by the user, and takes a curved trough shape, the elastic elements 15 and 16 tend to lift the flaps 10 relative to the absorbent pad 2 and thus separate the distal edges 14 of the two flaps 10, to an extent which increases from the two transverse edges of the diaper towards the middle of the crotch zone 5 as indicated in dashes in FIG. 2. The two opposite flaps 10 thus constitute barriers of longitudinal sealing and, due to their reciprocal connection in the two end zones 6 and 7, also form sealing pockets, in these zones, pockets whose depth depends on the length of the fixing zones 18. In the mode of embodiment according to Figures 4 and 5, the side flaps 10 are constituted by a single section of strip 19 disposed on the cover sheet 3, over the entire length of the diaper, on a la width substantially equal to the width of the absorbent pad 2 in the crotch area 5. The strip section 19 of a material permeable to air and preferably hydrophobic or impermeable to liquids is fixed to the cover sheet 3 by two longitudinal gluing lines 13 and by two transverse gluing lines corresponding to the lines 17 of the embodiment of FIGS. 1 to 3. The strip section 19 comprises, in the middle part of length, a median longitudinal slit 20, the two edges of which are furnished with longitudinal elastic elements 15 fixed in the stretched state on the respective edges of the strip section 19. The elasticized distal edges of two flaps 10 are thus obtained its proximal edges are defined by the gluing lines 13.

In the two end zones 6 and 7 of the diaper, the section of ribbon 19 which is not split forms belt pockets, the depth of which depends on the unsplit length of the section of ribbon 19 in each end zone 6 , 7. Also in this embodiment, when the diaper is worn by the user and takes a curved trough shape, the elastic elements 15 lift the flaps 10, so that the distal edges 14 of these flaps in the crotch area 5 in the manner indicated in dashed lines in FIG. 5. According to FIGS. 6 and 7, the median longitudinal slot 20 of the strip section 19 of FIGS. 4 and 5 is extended at each of these ends, in the vicinity of the junction of the crotch zone 5 with the two end zones 6, 7, by a transverse slot 21, thus delimiting, with the median longitudinal slot, two flaps 22 which can be folded outwards by example, as visible s in FIG. 7, and be fixed, for example by an adhesive line 23, in the folded state, thus constituting a narrow sheath in which is fixed in the stretched state a longitudinal elastic element 15 near the distal edges 14 which , due to the folding of the flaps, are here more distant from each other than in the embodiment of Figures 4 and 5. It therefore forms, between the distal edges 14 of the two flaps 10, a slot 24 wider than the slot 20 according to FIGS. 4 and 5.

When the diaper is worn by the user and takes on a curved trough shape, the elastic elements 22 lift the flaps 10, thus further spreading the distal edges 14 of the flaps 10. In the embodiment according to FIGS. 8 and 9, there is a diaper having the same general structure as according to the previous examples (support sheet 1, absorbent pad 2, cover sheet 3, hourglass shape of the sheets 1, 3 and cushion 2, longitudinal elastic elements 8 in the crotch area). This diaper also has two lateral sealing flaps 10 which, however, here consist of the same material of the cover sheet 3, which comprises, on the median part of the length of the diaper, a median longitudinal slot 25 Two elastic elements 26 are fixed in the stretched state on the external face of the two edges of the slot 25 extending to the two transverse ends of the diaper. In addition, a section of tape 27 made of a material permeable to liquids, for example a nonwoven, is arranged, over the entire length of the diaper, in the middle position between the absorbent pad 2 and the cover sheet 3, on a width at least equal to the width of the absorbent cushion 2 in the crotch area. This section of tape 27 is fixed to the support sheet 1 on the two transverse edges of the diaper. The cover sheet 3 is also fixed to this section of tape 27 on the one hand on the two transverse edges of the diaper and on the other hand along two longitudinal lines 28, for example glue lines, located in a position slightly set back with respect to the lateral edges of the absorbent cushion 2 in the crotch region 5. These fixing lines 28 define the proximal edges of the lateral flaps 10, the distal edges 29 of which, provided with elastic elements 26, are defined by the slot 25.

The embodiment of FIGS. 10 and 11 differs from the embodiment of FIGS. 8 and 9 in that the median longitudinal slot 25 formed in the cover sheet 3 to define the distal edges 29 of the two lateral flaps 10 has the form here. of a cutout delimiting an elongated opening, preferably rectangular, the width of this opening being much less than the width of the absorbent cushion 2, preferably less than half the width of the cushion 2 in the crotch area 5. From more, the cover sheet 3 here comprises, over its entire length, two double folds 30 in Z downwards (towards the cushion 2) arranged on either side of the opening 25, and the elastic elements 26 running along the distal edges 29 of the flaps 10 are fixed in the stretched state by gluing in the upper or lower folds of these double folds 30, the two folds of each double fold 30 being secured to one another by gluing or any other means so as to consolidate or stiffen the cover sheet 3 at this location and facilitate thus cutting with removal of material from the opening 25, performed subsequently.

H goes without saying that it is possible to use forms other than a Z for the double folds 30. For example, the double folds 30 may have the shape of an S, the elastic bands 26 being able to be fixed as previously in the folds upper or lower of these double S folds.

On the other hand, the material obtained by cutting the opening 25 can, if desired, be fixed by gluing either on the section of tape 27 or directly on the absorbent pad 2 thus constituting the section of the tape 27.

Finally, the section of liquid-permeable tape 27 having a width slightly greater than the width of the absorbent pad 2 in the crotch region 5 is here attached to the cover sheet 3 by two longitudinal lines 28 of gluing or welding located slightly outside the longitudinal edges of the cushion in the crotch area 5, which further increases the transverse dimension, that is to say the width or height of the flaps 10 whose proximal edges are defined by the connecting lines 28.

It goes without saying that the embodiments shown and described have been given only by way of illustrative and nonlimiting examples and that numerous modifications and variants are possible within the scope of the invention. Thus, in the embodiment of FIGS. 1 to 3, the two flaps 10, instead of being constituted by tabular sheath sections 11, could also be constituted by flat ribbons whose distal edges 14 could moreover overlap slightly, which would simplify the assembly of the distal edges 14 in the end zones 6, 7, for example by simple bonding or welding of these edges one on top of the other.

The provision of a wider slot 24 between the two flaps 10 according to the embodiment of Figures 6 and 7, would also be possible in the embodiment of Figures 8 and 9, that is to say with flaps 10 constituted by the material of the cover sheet 3.

The double folds 30 of the cover sheet 3 according to Figures 10 and 11 could also be used in the embodiment of Figures 8 and 9, and similar double folds could be provided in the strip section 19 of the embodiments FIGS. 4, 5 and 6, 7 for fixing the longitudinal elastic elements 15.

According to another alternative embodiment, the two lateral sealing flaps are constituted by two parallel longitudinal bands offset transversely and disposed above the absorbent pad and the cover sheet and whose inner longitudinal edges defining the elasticated distal edges of said flaps have a sinusoidal profile symmetrical with respect to the longitudinal axis of the diaper, thus forming a central longitudinal opening of elongated shape and overlapping end portions which are fixed together from the longitudinal ends of the opening to transverse edges of the diaper. Thus, said central opening is formed when it is necessary to make a cut in the strips.

It should be noted that in all the embodiments shown and described, the flaps 10 are advantageously made of a material which is breathable, but preferably hydrophobic or impermeable to liquids, such as a hydrophobic nonwoven or comprising a waterproof coating. In fact, an impermeable barrier to liquids is thus obtained extending over the entire periphery of the absorbent pad, making it possible to effectively suppress leakage of urine and / or faeces both around the legs of the user, it that is to say in the crotch zone 5, and at the waist, that is to say in the end zones 6 and 7.

Finally, although in all the embodiments shown and described, the diaper and its absorbent pad have a hourglass shape, the invention is also applicable to diapers having for example rectangular absorbent cushions.

It will be noted in this regard that if it is a question, in the description in relation to the side flaps 10, of the width of the absorbent pad 2 or of the longitudinal edges of the absorbent pad 2, this is always the width or the edges in the crotch area 5.

It will also be noted that in the present description, the term "exterior" refers to any element of the diaper directed towards the outside when the diaper is worn by the user. The term

"interior" has, on the contrary, been used to qualify any element located towards the user when the diaper is used.

Claims

1. Disposable absorbent diaper, comprising an outer sheet (1) of waterproof support, of generally rectangular shape, an absorbent pad (2) of generally rectangular shape, fixed on said support sheet, a sheet of permeable inner cover (3 , 27) covering the absorbent pad, fastening means (9) for closing the diaper around the waist of a user, longitudinal elastic elements (8) fixed in the stretched state to the support sheet, outside the longitudinal edges of the absorbent pad, and two side flaps (10) located above the cover sheet (3, 27) and extending above the absorbent pad so that their proximal edges (13, 28) are connected to said cover sheet along longitudinal lines located substantially above the longitudinal edges of the absorbent pad or recessed inwardly with respect to said edges and that their distal edges (14, 2 9) elasticized are located close to each other, characterized in that said side flaps (10) are interconnected at their distal edges (14, 29), from the transverse edges of the diaper at least to the corresponding transverse edges of the absorbent pad (2), thereby forming a peripheral sealing barrier around the entire periphery of the absorbent pad.

2. Diaper according to claim 1, characterized in that said side flaps (10) each consist of a section of tabular sheath (11) fixed in the flattened state on the cover sheet (3), along transverse edges of the diaper and along a longitudinal line (13) constituting the proximal edge of the flap, and that at least one elastic element (15) is fixed, in the stretched state, in said sheath, near the distal edge of the flap.

3. Diaper according to claim 1, characterized in that said two flaps (10) consist of the same section of tape (19) covering the cover sheet (3) over the entire length of the diaper and on the middle part of the width of the diaper while being attached to the cover sheet along its two transverse edges corresponding to the transverse edges of the diaper and along two longitudinal lines (13) constituting the proximal edges of the flaps, this section of tape having, on a median part of its length, a longitudinal median slot (20) the two edges of which are elasticized by longitudinal elastic elements (15) stretched to constitute the distal edges (14) of the two lateral flaps (10).

4. Diaper according to claim 1, characterized in that said flaps (10) are constituted by the cover sheet (3) having, on a median part of its length, a longitudinal median slot (25) of which the two edges are elasticized and constitute the distal edges (29) of the two flaps, and a section of tape (27) of width at least substantially equal to the width of the absorbent pad (2) is disposed between the cover sheet and the pad , over the entire length of the diaper, this section of tape being fixed both to the support sheet (1) and to the cover sheet (3) along the two opposite transverse edges of the diaper and to the cover sheet (3) on its two longitudinal edges opposite by two connecting lines (28) constituting the proximal edges of the two flaps (10).

5. Diaper according to claim 3 or 4, characterized in that said median longitudinal slot (20, 25) is extended, at its two ends, by two transverse slots (21) delimiting a flap (22) which, folded , defines a sheath in which is located said stretched elastic element (15).

6. Diaper according to claim 2, characterized in that said elastic element (15) is fixed in the stretched state in said sheath section (11) only at its two ends corresponding to the two transverse ends of the layer- cheeky.

7. Diaper according to any one of the preceding claims, characterized in that a second longitudinal elastic element (16) is fixed in the stretched state to each of said flaps (10) in the vicinity of the proximal edge (13, 28) of these.

8. Diaper according to claim 3 or 4, characterized in that said slot (20, 25) has the shape of a cutout defining an elongated opening of width less than half the width of the absorbent pad (2).

9. Diaper according to any one of claims 3, 4, 8, characterized in that the section of tape (19) or the cover sheet (3) constituting the two flaps (10) has, on all its length, two double folds (30) located on either side of said slot (20, 25), in which are fixed by gluing the longitudinal elastic elements (15, 26) elasticizing the flaps (10) at their distal edges ( 14, 29).