SE513205C2 - Ways of applying elastic members in a continuous web of material - Google Patents

Abstract

The invention relates to a method of applying elastic members onto an absorbent article intended for non-recurrent use, where each elastic member forms the leg elastic and is also in raised liquid barriers within different parts of one and the same absorbent article.

Description

. | I | I | 5 15 20 25 30 35 513 205 2 for the purpose of contracting the crotch portion of the diaper during use and by folding increasing the area and volume per unit length of the absorbent body. Thereby an increased absorption effect is achieved.

WO 88/00010 discloses a diaper having substantially rectilinear elastic which forms a V-shaped configuration. The elastic extends over the absorbent body of the diaper and defines an area which is deformed by the contractile action of the elastic. By stretching the elastic with rectilinear portions, a folding of the article as a whole is achieved mainly by the elastic 'attempt to reduce the length of the article.

US 4,801,345 discloses a method of making diapers. The method includes the application of elastic along the crotch portion of the diaper. In this case, the elastic extends along the long sides of the diaper and completely next to the absorbent body.

The purpose of the elastic is mainly to achieve a tight connection of the edge of the diaper to the wearer's legs. An additional effect is also a certain contraction and creasing of the absorbent body over the crotch portion.

EP 0,219,326 discloses a diaper with elastic which, when the diaper is in an extended, flat state, extends completely rectilinearly and completely to the side of the absorbent body.

Elastic is arranged partly at the outer edge of the diaper on either side of the crotch portion and partly in a portion on either side of the absorbent body of the diaper. In addition to maintaining an upright, sealing edge by means of the edging, i.e. an upright barrier, the elastic ensures a certain creasing and contraction of the absorbent body.

GB 2,234,257 refers to a trouser diaper with elastic, which extends partly around the waistband of the trousers, partly along the edge of the crotch portion towards the wearer's legs and partly across the crotch portion. The elastic for connection around the legs reduces the risk of leakage, while the elastic across the crotch portion is only arranged to enable a rational application of continuous elastic threads. adapted to diapers in trouser shape.

The construction and method are in particular GB 2,271,501 shows a diaper provided with raised barriers placed substantially parallel to the long sides of the absorbent body. Said barriers have, in the position of use of the article, a height varying from the surface of the absorbent body, which height is highest at the crotch portion of the diaper, in order to gradually decrease towards the respective waist portion.

DESCRIPTION OF THE INVENTION ;; An object of the present invention is to provide a method of applying elastic means to an invention is that liquid-absorbent article intended for single use, said elastic means forming both leg elastic and raised barriers within different parts of one and the same liquid-absorbent article. In this case two sets of elastic means are applied to the future liquid-absorbent article, mainly rectilinearly between different places on the future articles and with a periodicity of two products. By mainly rectilinear is meant that a certain curvature can be included in the application, but that no significant changes of direction occur between the above-mentioned places, whereby the number of accelerations per product on the laying equipment can be kept low.

The method of applying elastic in a continuous web to liquid-absorbent articles, or to a layer of material which is then used in the manufacture of absorbent articles, is mainly characterized in that a: first pair of elastic members is arranged symmetrically with an elastic member on each side of a web direction. extending 10 15 20 25 30 35 513. 205 4 line of symmetry in a repeating pattern with. a period corresponding to the length in the running direction of the web of two absorbent articles, the elastic members being applied so that at the beginning of the period they are at a predetermined distance from the line of symmetry, after which the elastic members are caused to converge over the length of a first half period to a minimum predetermined distance from the line of symmetry and during the length of a second consecutive half period is caused to diverge to the largest distance from the line of symmetry, and that a second pair of elastic members is arranged in a complementary pattern with a period length corresponding to the running direction of two absorbent articles. the elastic members at the beginning of the period are arranged at a minimum predetermined distance from the line of symmetry, after which the elastic members are caused to diverge during the length of the first half period to a maximum predetermined distance from the line of symmetry and during the length of the second, subsequent half period vergera to the smallest distance from the line of symmetry.

The fact that the two layout patterns are complementary does not mean that they necessarily constitute mirror images of each other when mirrored in a transverse line of symmetry through a single article. Although such a laying pattern is preferred, it is of course conceivable to use different laying patterns for the different pairs of elastic members. Such an asymmetrical layout can be used mirror-symmetrically to form absorbent articles with different elastic properties at the different end portions. This means that if the absorbent articles are produced with different appearances at their front and rear portions, respectively, they will be present on the continuous manufacturing path with two adjacent articles rotated 180 ° relative to each other. 10 15 20 25 30 35 513 2.05 By allowing the first pair of elastic members to converge at the line of symmetry, after a first half period of the laying pattern and then crossing each other before continuing over the second half period of the laying pattern, it is possible to obtain very long straight lines. elastic section. An elastic member laid out in this way can namely run straight over the entire length of the laying period, without changing the laying direction. Similarly, long straight elastic sections can be obtained for the second pair of elastic members, by allowing them to cross each other after each completed laying period. A considerable advantage of an elastic application method according to the invention is thus that it is possible to provide a relatively straight sections with a reduced number of changes of direction in the pattern. The elastic members laid out in the method according to the invention have, for each article, formed leg elastic, as well as sub-portions which form raised barriers on the liquid-absorbent article. COMPLETED LAYOUT PATTERN OF ABSORBING SUBPARTS WHICH BRIEF DESCRIPTION OF FIGURES: The invention will be described in more detail below with reference to the figures shown in the accompanying drawings.

Thereby showing.

Figure 1 is a cross-section through an absorbent article designed in accordance with the method of the invention, Figure 2 is a plan view of a manufacturing line of absorbent articles with a first elastic layer according to the invention, a production line of Figure 3 is a plan view of a absorbent articles with a second elastic layer according to the invention and Figure 4 an absorbent article with elastic laid according to the invention.

DETAILED DESCRIPTION OF EMBODIMENTS: The method of laying out elastic members according to the invention will be described in more detail below, by means of two embodiments. Diapers have been chosen as an illustration, but of course the method is also applicable to other types of liquid-absorbent articles.

The diaper shown in Fig. 1 is built up of a casing 4, which encloses a core in the form of an absorbent body 1. In the flat, elongated state in which the diaper is shown, the absorbent body 1 has a relatively flat main shape, with two mutually facing main surfaces , namely an inside 2 intended to be inwardly facing the user when using the diaper and an outer side 3, intended to be facing outwards away from the user. The absorbent body 1 circumferentially surrounds the absorbent body 1 otherwise has rounded edges which give an expedient outer contour which is anatomically adapted to the wearer's body. Although the absorbent body 1 in the example shown is substantially uniformly thick, it is of course possible to use, for example, an absorbent body with a central portion with a slightly larger thickness.

The cover 4 is in the example shown formed by two layers 5,6 with mutually different properties, which are located against the inside 2 and outside 3 of the absorbent body 1 and enclose the absorbent body in that the two layers 5,6 are connected to each other outside the absorbent body 1 and form a circumferential flange-like edge portion 18 for the diaper as a whole. The two layers 5,6 are placed close together in the edge portion 18 and are interconnected, for example by gluing or welding with heat or ultrasound.

The components used to form the diaper shown may be any of the components commonly used for such purposes. The layer 5 which in use is facing the user may be any soft, flexible, liquid-permeable material, such as non-woven fabric, or a soft perforated plastic film of polyethylene or the like. The layer 6 on the outside 3 is suitably of a liquid-tight material, such as a thin (for example 20p) plastic film of polyethylene, polyvinyl chloride or the like.

The absorbent body 1 may consist of cellulosic fibers, tissue, foam material, various types of superabsorbent material, or the like. By superabsorbent material is meant polymeric materials which have the ability to absorb several times their own. weight of 'liquid, forming an aqueous gel. Of course, combinations of the above materials can also be used.

As can be seen from the figures, in particular from Fig. 2, the diapers in the examples shown have a main shape of a symmetrical hourglass, with a centrally located crotch portion 15 from which the diaper is extended in one direction towards a rear portion R and in the opposite direction towards a front portion F , which portions are intended to connect, when the diaper is in the position of use, to corresponding portions on the wearer's body. The diapers shown thus have a substantially elongate shape and are formed substantially symmetrically about a longitudinal line of symmetry S and about a transverse line of symmetry S '. Thus, the diapers shown in Figs. 2 and 3 have two elongate side edges 7,8, and two short sides 9 , 10. The short sides 9,10 connect the side edges 7,8 at four corner areas 11, 12, 13 and 14, a first corner area 11 being found at the intersection of the first short side 9 of the finished diaper 9 with the first elongate side edge 7. The second corner area 12 is found at the intersection of the first short side 9 of the finished diaper with the second elongate side edge 8. Correspondingly, the third corner area 13 is found at the intersection of the second short side 10 of the finished diaper 10 with the first side edge 7 and the fourth corner area at the second short side 10. cutting with the other side edge 8.

In the manufacture of absorbent articles according to the invention, this is done by moving the future articles in a continuous path in the direction of the longitudinal line of symmetry S. In a first exemplary embodiment, shown in Fig. 2, the future article is built up successively by adding the various components to the continuous manufacturing path. In this case, first the liquid-permeable surface layer 55 on the manufacturing web is applied, after which the elastic members are applied and then the absorbent body 1 is applied. Finally, the liquid-tight outer layer 6, as well as any other details, are applied.

When the application of elastic members takes place according to the exemplary embodiment shown in Fig. 2, two sets of elastic members, A, B, are applied; A ', B', on the liquid-permeable surface layer 5, these means A, B; A ', B', on the one hand form leg elastic 16, and on the other hand are included in raised liquid barriers 17 within different areas of the absorbent articles.

Said first pair of elastic members, A, B, and second pairs of elastic members A ', B', respectively, are thus applied starting from two liquid-absorbent articles lying one after the other in the running direction of the production path. The first pair of elastic members A, B first members .A are attached thereto. at the first corner area 11 of a first liquid-absorbent article. The second elastic member B is attached to the second corner area 12 of the first liquid-absorbent article, which is located across the article as seen from said first corner area 11, after which the first pair of elastic members organs A, B first organs A, starting from the first corner area 11 of said first article, are applied substantially rectilinearly to the line of symmetry S at the second short side of the first article 10. This adjoins the first short side of said second article 9. From the first short side of the second article it continues substantially rectilinear application to the fourth corner area 14 of said second article, after which the application changes direction and the elastic member A is correspondingly applied substantially rectilinearly obliquely across two successive articles to a corner area 13. Correspondingly, the third pair of elastic members A of the first fourth article is applied , B other organs B mainly straight line from the second corner area 12 of said first article to the line of symmetry S at: the second short side 10 of the first article, which adjoins the first short side of said second article 9. From there the substantially rectilinear application to the third corner area 13 of said second article continues, after which the application changes direction and said the second elastic member B is similarly applied rectilinearly obliquely over two successive fourth fourth corner areas 14. In the same way and at the corresponding place mainly articles to one article, the application of the second pair of elastic members A ', B' to the first and second corner area 11.12. The period for the application of this second pair of elastic members ends at a configuration of elastic members lying in the direction of manufacture after the fourth article, in a continuous manner. fifth article. In this case, in an application method according to a second exemplary embodiment, which is shown in Fig. 3, the elastic members form both leg elastic and they are included in erected liquid barriers.

The elastic members are applied in a manner similar to that described in connection with Fig. 2.

Characteristic of the elastic layout shown in Fig. 2 is that two sets of elastic members, A, B; A ', B', are applied to the liquid-absorbent article, sub-elements 16,17 of the elastic members A, B; A ', B', in different areas of the absorbent article partly form leg elastic 16, partly are included in raised liquid barriers 17.

The elastic members A, B; A ', B', are arranged starting at two consecutive future absorbent articles and the application of the elastic members takes place with a periodicity of two future, continuous absorbent articles, before these are divided into individual articles. The application takes place by applying a first pair of elastic members, A, B and second pairs of elastic members A ', B', starting with two liquid-absorbent articles lying one behind the other in the manufacture, the first pair of elastic members A, B first elastic members A is attached to the first corner area 11 of a first liquid-absorbent article and the second elastic member B is attached to the second corner area 12 of the first liquid-absorbent article. The second corner area 12 is located across the article, seen from said first corner area. The first pair of elastic members A, B first elastic members A, are then applied, starting from the first corner area 11 of said first article, substantially rectilinearly to, or near, the second short side 10 of said first article intersecting with the line of symmetry S, after which the first the elastic member A changes direction and this is applied substantially rectilinearly to a corner area 13 following the second direction of article following the manufacturing directions. The first pair of elastic members A, B second 10 15 20 25 30 35 513 205 11 member B, is applied correspondingly starting at the second corner area of said first article 12, after which it is applied substantially rectilinearly to, or in the vicinity of, the second side of symmetry line S of said first article 10, after which the application of the second cut with the elastic member B changes direction and is applied substantially rectilinearly to a fourth corner area 14 of the subsequent second article 14. In the same way and in equivalent the application of the second pair of elastic members A ', B' begins on the first 11 and second corner area 12 of a second article, the period for the application of this second pair of elastic members A ', B' ending on one, in the direction of manufacture after the second article lying, third article. By utilizing this method of application, a desired configuration of elastic members is obtained in a continuous manner.

By e.g. gluing, or some form of welding, the parts of the elastic members A, B and A ', B', respectively, which extend from the crotch portion 15 of the future liquid-absorbent articles, are attached in the direction of the longitudinal line of symmetry S to the short sides 9 of each article, 10 to the inside of the surface layer 5. When the elastic members are attached only to the inside of the liquid-permeable surface layer 5 and not to the absorbent body 1, and when certain areas of said surface layer 5 which are adjacent to the ones subsequently bonded from either, the absorbent body has raised liquid barriers 17 on the elastic member, not the absorbent body 1. top of the liquid absorbent article. It is also conceivable that the elastic members A, B and A ', B' do not bond to any surface within the areas where the liquid barriers 17 are formed, but can move freely within an area where the surface layer 5 and the absorbent body 1 are not connected, these areas by the action of the elastic members form tunnel-like raised liquid barriers 17. In the described exemplary embodiments, prepared according to the invention, the parts of the elastic members A, B and A ', B', respectively, which extend from the crotch portion 15 of the article against the four corner portions of the article 11, 13, 13, 14, to the surrounding material layers in such a way that these parts form leg elastic 16 on the finished product.

In a further embodiment of the invention, shown in Fig. 4, all elastic members are applied to a material layer, or to a laminate layer, which layer itself forms a trouser-like unit. Attached to the outside of this unit is the absorbent body itself, which is provided with a liquid-tight backing layer. The trouser-like unit is in this case provided with one or more openings through which urine and faeces are transferred to the absorption body.

The invention is not to be considered limited to the above-mentioned embodiments, but is also applicable to other embodiments within the scope of the claims of the invention.

It is conceivable, for example, that the elastic members are arranged on the side of the surface layer 5 which in use faces the user, the parts of the elastic members included in the raised liquid barriers 17 being covered by strips of liquid-tight material attached to the surface of the layer 5 along their edges in such a way that said barriers become liquid-tight.

All conceivable combinations of the embodiments described above are further intended to be encompassed by the invention.

Claims (12)

10 15 20 25 30 35 513 205 13 PATENT REQUIREMENTS A method of continuously applying elastic members (A, B; A ', B') in a continuous web to form elastic on absorbent articles such as diapers, incontinence guards, or sanitary napkins, characterized in that a first pair of elastic members (A, B) symmetrically with an elastic member (A, B) on each side of one: in the running direction of the web extending line of symmetry (S) in a repeating pattern with a period corresponding to the length in the running direction of the web of two absorbent articles, the elastic members ( A, B) are applied so that at the beginning of the period they are at a maximum predetermined distance from the line of symmetry (S), after which the elastic members (A, B) are caused to converge over the length of a first half period to a minimum predetermined distance from the symmetry line (S) and during the length of a second consecutive half period is caused to diverge to the greatest distance from the symmetry line (S), and that a second pair of elastic members (A ', B') are arranged in a complementary pattern. nster with a period length corresponding to the length in the running direction of the web of two absorbent articles, the elastic members (A ', B') at the beginning of the period being arranged at a minimum predetermined distance from the line of symmetry (S), after which the elastic members '(A', B ') is caused to diverge during the length of the first half period to a maximum predetermined distance from the line of symmetry (S) and during the length of the second, subsequent half period is caused to converge to the smallest distance from the line of symmetry (5) - A method according to claim 1, characterized in that the first pair of elastic members (A, B) are caused to cross each other after the first half period. 10 15 20 25 30 35 513 205 14 3. A method according to claim 1 or 2, characterized in that the second pair of elastic members (A ', B') are caused to cross each other after each whole period. 4. A method according to any one of claims 1-3, characterized in that the elastic members (A, B; A ', B') are arranged so that they diverge and converge substantially rectilinearly. 5. A method according to any one of claims 1-4, characterized in that the elastic members (A, B; A ', B') are attached to a liquid-permeable material layer. A method of producing, in a continuous web of material, disposable liquid absorbent articles, such as diapers, incontinence guards or sanitary napkins, each article being elongated around a longitudinal symmetry line (S) extending symmetrically in the material direction of the material. ) with an inside (2) and an outside (3) enclosed by a casing (4) comprising a liquid-permeable surface layer (5) which is arranged against the inside (2) of the absorbent body and a substantially liquid-impermeable surface layer (6) which is arranged against the outside (3) of the absorbent body. ), the article receiving two elongate side edges (7,8), and two short sides (9, 10), which connect the side edges (7,8) at four corner areas (11, 12,13,14) and which article is further provided with a first pair of elastic members (A, B) and a second pair of elastic members (A ', B'), characterized in that the first pair of elastic members (A, B) and the second pair of elastic members, respectively means (A ', B') are applied starting with two successive liquid-absorbent articles in the direction of manufacture, the first pair of elastic members (A, B) first members (A) being attached to a first the first corner area (11) of the liquid absorbent article and the second member (B) are attached to the second corner area (12) of the first liquid absorbent article which is located across the article from said first corner area (11), after which the first pair of elastic members (A, B ) first body (A), starting from the first corner area (ll) of said first article, is applied substantially rectilinearly in the direction of the line of symmetry (S) at the second short side of the first article (10), which adjoins the first short side of a second article (9) , to continue therefrom the substantially rectilinear application to the fourth corner area (14) of said second article, after which the application changes direction and the first elastic member (A) in the first pair of elastic members (A) (B) is similarly applied substantially rectilinearly obliquely across two successive articles to the third corner area of a fourth article (13) and on. correspondingly, the first pair of elastic members (A, B) second members (B) are applied substantially rectilinearly from the second corner area (12) of said first article to the longitudinal line of symmetry (S) at the second short side (10) of the first article, which is adjacent to said first short side (9) of the second article, to continue the application to the third corner area of said second article therefrom substantially rectilinearly (13), after which the application changes direction and the elastic member (B) is correspondingly applied substantially rectilinearly across two successive articles to a the fourth corner area (14) of the fourth article, in the same way and at the corresponding place, the application of the second pair of elastic members (A ', B') to the first and second corner areas of a second article (l1, l2), the period of application of the second the pair of elastic members (A ', B') terminate on a fifth article lying in the direction of manufacture. 10 15 20 25 30 35 513 205 16 A method according to claim 6, wherein each liquid-absorbent article has a branch portion (15) centrally located in the longitudinal direction of the article, characterized in that parts (17) of the first pair of elastic members (A, B) and the second pair of elastic members, respectively means (A ', B'), which are arranged between the crotch portion (15) on each article and the line of symmetry (S) at the short sides (9,10) of the article, are part of liquid barriers on the finished absorbent article which can be raised from the absorbent body (1). Method according to claim 7, characterized in that parts (16) of the first pair of elastic members (A, B) and the second pair of elastic members (A ', B'), respectively, which are applied between the crotch portion (15) on each article and the four corner portions of the article (ll, 12,13,14), form leg elastics on the finished absorbent article. 9. A method of producing, in a continuous web of material, disposable liquid absorbent articles, such as diapers, incontinence guards or sanitary napkins, wherein the article is elongated, the running direction of the web extending around each other in a line of symmetry (S) is substantially symmetrical. ) with an inside (2) and an outside (3) enclosed by a casing (4) liquid-permeable surface layer (5) inside (2) of the absorbent body and a substantially liquid-impermeable surface layer (6) which is arranged against comprising one which is arranged towards the outside of the absorbent body (3) ), the article receiving two elongate side edges (7,8), and two short sides (9,10), which connect the side edges (7,8) at four corner areas (l1,12,13,14) and which article is further provided with a first pair of elastic members (A, B) and a second pair of elastic members (A ', B'), characterized in that the first pair of elastic members (A, B) and the second pair of elastic members, respectively means (A ', B') are applied starting from 10 15 20 25 30 35 513 205 17 two successive liquid-absorbent articles in the direction of manufacture, the first pair of elastic members (A, B) first members (A) being attached to a first the liquid-absorbent article in the first corner region (11) and the second member (B) is attached to the second corner region (12) of the first liquid-absorbent article which is located across the article from said first corner region (11), after which the first pair of elastic members (A, B) first member (A), starting from the first corner area (11) of the said first article, is applied substantially rectilinearly to, or near the second short side (10) of the first article, intersection with the line of symmetry (S), after which the application of the first elastic member (A) changes direction and takes place mainly rectilinearly to a third corner area (13) of the second article following the running direction of the production path, the first pair of elastic members (A, B) second members (B) are applied to m correspondingly starting at the second corner area (12) of said first article, after which it is applied substantially rectilinearly to, or near the intersection of the second short side (10) of the first article with the line of symmetry (S), after which the application of the second elastic member (B) changes direction and takes place substantially rectilinearly to a fourth corner area (14) of the second article following the running direction of the manufacturing path, in the same way and at the corresponding place the application of the second pair of elastic members (A ', B') begins on the first and second corner areas of a second article (1l, l2), the period of application. of 'the second (Ã', B ') direction of manufacture lying third article. the pair of elastic members terminate on an i 10.. method according to claim 9, liquid-absorbent article having a branch portion (15) centrally located in the article, each longitudinal direction being characterized in that parts (17) of the first pair of elastic members (A, B) and the second pair, respectively, Elastic means (A ', B'), which are applied between the crotch portion (15) on each article and the line of symmetry (S) at the short sides (9, 10) of the article, comprise liquid barriers of the absorbent body (1) which can be raised from the absorbent body (1). . Method according to claim 10, characterized in that parts (16) of the first pair of elastic members (A, B) and the second pair of elastic members (A ', B'), respectively, which are applied between the crotch portion (15) on each article and the four corner portions of the article (11, 12, 13, 14) form leg elastics on the finished absorbent article. An absorbent article, such as a diaper, an incontinence guard, or a sanitary napkin, characterized in that it is manufactured in accordance with any one of the methods of claims 1-11.