MXPA97009954A - An absorbent article such as a diaper, an incontinence protector, a sanitary towel or a semile article - Google Patents

Abstract

The invention relates to an absorbent article such as a diaper, an incontinence protector or a sanitary napkin which includes a superabsorbent material in the form of a film or band having slots placed therein. The film or band is stretched transversely to the longitudinal direction of the grooves, in such a way as to form an aperture.

Description

"AN ABSORBENT ARTICLE SUCH AS A DIAPER, AN INCONTINENCE PROTECTOR, A SANITARY TOWEL OR A SIMILAR ITEM" BACKGROUND An absorbent article such as a diaper, sanitary napkin or incontinence protector will normally include a liquid permeable outer sheet, a liquid impervious barrier sheet and an absorbent body placed therebetween. An absorbent article of one of the aforementioned classes has a generally rectangular shape including two long sides and two short sides. The external canvas is that part of the absorbent body that remains close to the body of the wearer during use, while the barrier layer is that part of the absorbent article that is distant from the wearer's body. The outer canvas is usually comprised of a perforated, non-woven plastic film, or a plastic and non-woven laminate. The plastic can be a thermoplastic material such as polyethylene. The non-woven material can be comprised of natural fibers such as cellulose or cotton fibers or synthetic fibers, such as polyethylene, polypropylene, polyurethane, nylon or regenerated cellulose fibers. The object of the external canvas of an absorbent article of the aforementioned kind is to conduct the fluid towards the article and prevent rewetting of the wearer's skin and create with it a dry surface in contact with the skin. A dry surface in that part of the article that remains against the skin of the user in use is important for the comfort of the user and also to avoid irritation of the skin. The barrier layer is produced in a material impervious to the liquid and functions to prevent the liquid from leaking from the underside of the absorbent article. The barrier layer may comprise any type of material that fulfills the criterion of liquid impermeability that is sufficiently flexible for the purpose for which it is intended. Examples of suitable barrier layer materials are plastic, non-woven and laminated films thereof. The plastic film can comprise, for example, polyethylene, polypropylene, polyester. The absorbent body is usually produced from cellulose pulp. The paste can exist in rolls, sardos or leaves that have been defibrated dry and transformed into a spongy state in a paste mat. As mentioned above, the absorbent body may consist of cellulose fibers. Examples of other fibers conceivable in this respect are cotton fibers and synthetic fibers. The use in the absorbent body of a foamed material is also known. Materials called superabsorbents are sometimes used with the intention of improving the liquid retention capacity of the absorbent body, the superabsorbent materials being polymers that are capable of absorbing several times their own weight of water or body fluid. Examples of these superabsorbent materials are polyacrylates, starch or modified cellulose such as carboxymethyl cellulose. The superabsorbent material is usually added to the absorbent material in powder form, and either mixed uniformly or concentrated in certain parts of the absorbent body. The superabsorbent material can also be supplied to the absorbent body in the form of a band or a film. The advantage with this method of administration is that the superabsorbent material can be easily applied in the manner proposed and in the correct amount. The application of the superabsorbent material in the form of a film or web also avoids the potentially harmful dust that is generated when handling all types of powder material. The inconvenience with the superabsorbent material in the form of a film or web is that this method of administration can easily result in a so-called blocking of the gel. Gel blockage occurs due to rapid filling of the superabsorbent material when applied to the liquid, thus preventing further dispersion of liquid through the absorbent body. Naturally, this can also occur when the superabsorbent material is applied in powder form, even though the risk of gel blocking is naturally greater when the superabsorbent material has been concentrated to a smaller area of the absorbent body, as is the case when applies to the superabsorbent material in a film or web form.

OBJECT OF THE INVENTION The object of the present invention is to alleviate or solve the aforementioned problems associated with the application, the generation of fine powder and the blocking of gel, together with the use of the superabsorbent materials in absorbent articles.

EXHIBITION OF THE INVENTION The aforementioned problems associated with the administration of the superabsorbent material are solved by means of the present invention, by applying the superabsorbent material in the form of a film or a band which has been provided with grooves and elongated transversely towards the direction of the grooves. This results in a band or film of superabsorbent material having a three-dimensional structure and including holes. It is known to produce the superabsorbent material in a film form for use in absorbent articles such as incontinence guards. U.S. Patent No. 4,643,726 discloses an insert for use in the incontinence guard which is inte to be used in conventional uwear. The insert includes a non-woven canvas permeable to the inner liquid, an outer sheet of liquid-impermeable polyethylene film, a single absorbent layer of spongy cellulose placed therebetween, and a layer of superabsorbent polymer placed between the inner canvas and the inner sheet. absorbent layer. The superabsorbent polymer layer is perforated, in order to facilitate liquid passage down through the layer. Even though these perforations prevent the blocking of the gel to a certain degree, at least on the first occasion of wetting the openings will gradually decrease in size as the layer is wetted, due to the swelling of the superabsorbent material. The liquid inlet time will therefore significantly decrease with the repeated wetting of the layer. In accordance with the present invention, the grooved superabsorbent web or film may include a large number of through penetrating slots or grooves. Since the band or film is stretched transversely with respect to the longitudinal direction of the grooves, the grooves will open because the material on opposite sides of the respective grooves is twisted out of the plane of the film or band to form surfaces that they are raised or sunk respectively from the plane of the layer. The grooves are preferably straight, although it may also have some other appropriate shape that will allow the adjacent layer parts to the grooves to twist out of the plane of the layer and thereby form raised edges when the film or web is stretched. . When the grooves are mutually displaced in the manner described above, the edges of the grooves will rise as the web or film extends transversely to the longitudinal direction of the grooves, such that the material will be transformed from a two-dimensional structure. to a three-dimensional network structure wherein the widened grooves form rhomboidal openings. Because the edges of the openings will be placed in different planes, a large open area is obtained and the openings will not swell together as the surface is wetted to the same degree as if the edges of the openings were placed in one and the same plane. The openings therefore maintain a wide open area even after the layer is moistened, thus preventing the blocking of the gene and achieving a high liquid inflow rate even after the repeated wetting of the layer. In a conceivable method for producing an absorbent article that includes an absorbent body made of foamed pulp in accordance with the present invention, a core of pulp mat is first formed. The elongated slotted superabsorbent film is then placed on the pulp core and a second mat core is formed at the top and through the superabsorbent film. A product is thus obtained that is permeable to the ends beyond the film or the superabsorbent web. Thus, when the mats are formed, the pulp fibers will be placed per se in the openings formed in the slotted and elongated superabsorbent film. This aids in the transport of liquid past the superabsorbent film and also disperses the liquid to different parts thereof. In another conceivable method for manufacturing an absorbent article according to the invention, the strip or film or superabsorbent material is placed directly adjacent to the absorbent body on that side thereof which is intended to be against the wearer during use. An external canvas is then placed on top of the superabsorbent film. In another conceivable method for manufacturing an absorbent article in accordance with the present invention, the web or the film of the superabsorbent material is placed directly adjacent to the absorbent body on that side thereof which is intended to be oriented towards the barrier layer.

The invention is not limited to absorbent articles that include an absorbent body comprising cellulose formed on a mat, but can be applied with other types of absorbent bodies, such as absorbent bodies made of foamed material or a cellulose material of preformed webs . The invention will now be described in greater detail with reference to the exemplary embodiments thereof and also with reference to the accompanying drawings. The invention is not limited to the exemplary embodiments described and illustrated nor to the drawings themselves, which are only intended to explain and illustrate the invention. Figure 1 is a cross-sectional view of a band of superabsorbent material including grooves. Figure 2 is an enlarged sectional view of the extended or elongated grooved material. Figure 3 is a view of the slotted material extended or elongated from above. Figure 1 illustrates an absorbent body constructed in accordance with the invention. The body can be produced by forming a mat of a first core 1 of paste or a layer of paste. The superabsorbent web 2 formerly grooved and extended is placed on top of the first core 1 of paste, after which a second core 3 of paste or layer of paste is formed on the top of the strip 2. When a superabsorbent web constructed in accordance with the invention, is obtained by forming the mat of the second core of paste, an absorbent body whose pass fibers will extend through the holes formed in the superabsorbent web 2 as the web is lengthened and Slots open accordingly. This results in a product that is highly permeable to liquid through the superabsorbent band 2. The grooved web or film 2 of the superabsorbent material is applied to the absorbent product in an elongated state, more specifically, as long as it extends in a direction transverse to the longitudinal direction of the grooves. The material 4 placed on both sides of each groove is twisted or rotated out of the plane of the film or band to form edges 5 that project up and down from the plane. The grooves expanded in this way form diamond-shaped openings 6 whose size will depend on the degree to which the band or film has been lengthened. Preferably, the openings 6 will be in a row opposite the spaces between the openings in the adjacent figures. The distance between slots in the longitudinal direction will preferably be smaller than 1.5 times the length of a slot, appropriately less than or equal to the length of the slot, preferably smaller than the length of the slot. The distance between the mutually adjacent rows of slots will preferably be smaller than 1.5 times the length of the slot, appropriately smaller or equal to the length of the slot, preferably smaller than the length of the slot. The film or band 2 of the slot can be applied to cover the entire absorbent core or to only cover parts thereof. For example, the film or band 2 may be applied in order to cover only the region of anticipated wetting of the absorbent article and the regions bordering the moistened region. It is also conceivable to provide the film or web with one or more larger openings in the vicinity of the anticipated wetting region in order thereby to improve the liquid permeability of this region of the article. It is also conceivable to vary the lengths of the grooves in different regions, such that the grooves have a longer length thus providing larger openings, for example, in those regions where the more intense entry of the liquid can be expected to occur. . Figure 3 shows a diaper including a grooved film of superabsorbent material. The diaper is from the side that is intended to be oriented towards the user during use, which has a part 7 that is intended to be against the stomach of the user and a part 8 that is intended to be against the back of the user. The grooved film 2 would normally not be visible, even though Figure 2 shows a section of the diaper in which the outer canvas and possibly the absorbent body that is above it have been lifted to allow the grooved film 2 to be seen from above.

Claims (10)

R E I V I N D I C A C I O N S

1. An absorbent article such as a diaper, an incontinence protector or a sanitary napkin, including an absorbent body (1, 3) and a superabsorbent material (2) in the form of a band or film applied to the body or in close proximity thereto; whose band or film (2) is grooved and elongated transversely to the longitudinal direction of the grooves which form wider openings (6) with portions (4) of the band material (2) being placed between the openings, characterized in that the parts of the web material (4) placed between the openings (6) are twisted or rotated to respectively form edges projecting upwards and downwards (5) as seen in relation to an imaginary plane of the band (2) or film in a non-elongated state. An absorbent article according to claim 1, characterized in that the grooves are placed in longitudinally extending rows which are generally parallel to the longitudinal axis of the article. An absorbent article according to claim 1, characterized in that the grooves are placed in longitudinally extending rows which are generally transverse to the longitudinal axis of the article. 4. An absorbent article according to one or more of the preceding claims, characterized in that the openings (6) of the rows are opposite the spaces between the openings (6) of the adjacent rows. An absorbent article according to one or more of the preceding claims, characterized in that the distance between the ends of two slots mutually in sequence is smaller than 1.5 times the length of the slot. 6. An absorbent article according to one or more of the preceding claims, characterized in that the distance between the rows is smaller than 1.5 times the length of the slot. An absorbent article according to one or more of the preceding claims, characterized in that the superabsorbent strip (2) or film is placed alone in a part of the length and / or width of the absorbent body (1, 3). An absorbent article of compliance one or more of the preceding claims, characterized in that the band (2) or film includes one or more larger openings in a region opposite a region of the article that is anticipated to be wetted. An absorbent article according to one or more of the preceding claims, characterized in that the lengths of the slots and therefore the sizes of the openings (6) vary in different regions of the band (2) or film. A method for manufacturing an absorbent structure for use in an absorbent article, such as a diaper, an incontinence protector or a sanitary napkin, which includes placing a plurality of through slits in a band (2) or a film of superabsorbent material , after which the band or film is subjected to elongation transversely to the longitudinal direction of the slots, whereby the slits are enlarged to form openings (6), characterized by twisting or rotating the parts of the material (4) in both sides of the respective slots outside the plane of the band (2) or the film to form edges (5) projecting respectively up and down from the plane, therefore, the band or the film is manufactured to change from a two-dimensional structure to a three-dimensional network structure, after which the slit and the elongated band (2) or film is joined with an absorbent body (1, 3). ) made of cellulose formed from a mat, foamed material or cellulose material from a continuous preformed tape.