RU2414875C1 - Absorbing product of underpants type and method of manufacturing adsorbing products of underpants type - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to absorbing product of underpants type, which contains basic structure, which containing front panel, which has front end edge and first and second side edges, back panel, which has back end edge and first and second side edges, and perineal panel, located between front and back panels. At least, one of said front and back panels contains elastic laminate from nonwoven material and film, and core, incorporated with basic structure. First and second side edges of front panel are connected by side seams with respective first and second side edges of back panel. Each side seam is formed in, at least, partly weldable, connecting element. Connecting element contains first part, connected to side edge on front panel, and second part, connected to respective side edge of back panel Invention also relates to method of manufacturing absorbing product of underpants type.

EFFECT: invention makes it possible to create absorbing product of elastic underpants type, which contains elastic multi-layer materials and has strength, sufficient to bear efforts, which appear in putting on and wearing product.

22 cl, 4 dwg

Description

FIELD OF THE INVENTION

The invention relates to a coward-type absorbent article comprising a base structure comprising a front panel having a front end edge and first and second side edges, a rear panel having a rear end edge and first and second side edges, and a crotch panel located between the front and rear panels, and a core component integrated with the base structure, wherein the first and second side edges of the front panel are connected by side seams to the corresponding first and second side edges of the rear ate.

BACKGROUND OF THE INVENTION

Panty-type absorbent articles typically include a cowl-shaped base structure and an absorbent core component combined with the base structure. When creating products such as underpants, the main goal is to make them look like ordinary underwear to the greatest extent possible. Therefore, absorbent articles, such as diaper pants, hygiene pants and panties used for incontinence, are made with the possibility of their convenient and tight fit to the user. It is also desirable that the products be configured to pull them up and pull them down the hips of the user in order to enable the user or carer to easily remove the stained product and replace it with a new clean product. For these reasons, the base part of the product is usually made of a material that lends itself to elastic stretching, at least around the waist and in areas intended to be “overlaid” over the user's thighs.

Traditionally, the base part of absorbent articles such as pants was made of layers of inelastic thermoplastic non-woven material having elastic elements, such as threads or tapes, placed between the layers to give elasticity to selected parts of the base part. In these products, the fibers and the joints of the nonwoven webs remain unbroken during the manufacture of the base structure and can be used to form durable and nonetheless separable welds and joints between parts of the base part. However, to meet the demand for products such as underpants, which are more similar to the subject of underwear, traditional elasticization by means of elastic elements was replaced by laminates made of elastic non-woven materials and films.

One example of an elastic laminate for use in absorbent articles such as underpants is disclosed in WO 03/047488. Laminate consists of an elastic film located between two layers of non-woven material. During the manufacture of the elastic laminate, nonwoven layers were attached to the film, after which the laminate was subjected to an activating treatment, which involves stepwise stretching of the laminate, which causes the joints and fibers to break in the nonwoven webs. As a result, the elasticity of the activated laminate will be substantially the same as the elasticity of the elastic film. A problem associated with activated laminates of this type, consisting of a nonwoven material and a film, is that welds formed in mechanically weakened materials have low tensile strength. This means that there is a risk that the seams will burst prematurely when a product such as underpants is worn on the wearer or when worn.

Other examples of elastic laminates used in the creation of products such as pants are disclosed in documents WO 2005/122984 and WO 2005/122985. The materials in these applications differ from the materials disclosed in WO 03/041988 in that the compounds and fibers of at least one layer of nonwoven material in the elastic laminate were not completely torn. Instead, the layer retains some residual strength. International applications according to PCT WO 2005/122984 and WO 2005/122985 describe laminates in which a combination of elasticity with the softness and puncture resistance of laminates is provided. However, the welded side seams in pant-like products containing similar laminates still exhibit low tensile strength compared to the welded seams of traditional underpants made from layers of non-woven material that were elasticized with elastic threads or strips.

Panty type absorbent articles are typically formed with seams or joints on the sides of the base structure for attaching the front of the article to the back and for forming panties having a waist opening and a leg opening. Typically, the side joints are positioned so that they will be on the hips of the wearer during use of the absorbent pants, but it is also known to place the side joints to a greater extent in the front of the product.

The side seams are preferably made so that they give sufficient integrity to the base part when it is worn and worn. This means that the side seams must withstand the tensile stresses that occur when pulling a product such as shorts up the hips of the user, as well as any tension that may occur in the side seams as a result of movements of the user during use of the product. However, it has been proven that a significant advantage is provided if it is possible to separate the side seams in an adjustable manner after using the product so that the soiled product can be easily removed from the user without having to pull it down along the legs. Disconnectable side seams are most easily formed by welding technologies such as ultrasonic welding or heat welding of thermoplastic components in the base material. A problem associated with elastic laminated materials used to form an elastic base structure is that they generally have poor weldability, which leads to fragile side seams that will break when put on the product or when the product is worn.

Accordingly, an object of the invention is to provide an absorbent article, such as elastic underpants, containing elastic multilayer materials and having a strength sufficient to withstand the forces arising from putting on and wearing the article.

In addition, the aim of the invention is to provide an absorbent article such as elastic underpants containing elastic multilayer materials and having opening side seams.

An additional objective of the invention is to develop a simple and effective method of manufacturing an absorbent product such as elastic pants, having side seams that demonstrate strength sufficient to withstand the forces arising from putting on and wearing the product.

SUMMARY OF THE INVENTION

In accordance with the invention, there is provided an underpants-type absorbent article comprising a base structure comprising a front panel having a front end edge and first and second side edges, a rear panel having a rear end edge and first and second side edges, and a crotch panel located between the front and back panels, wherein at least one of said front and back panels comprises an elastic laminate of non-woven material and a film, and a core integrated with the base structure, while the first and second side edges of the front panel are connected by side seams to the corresponding first and second side edges of the rear panel, each specified side seam being formed in a weldable connecting element, the connecting element comprising a first part attached to a side edge on the front panel and a second a part attached to the corresponding side edge on the rear panel, wherein said first and second parts of said connecting element are heat-sealed to form said th side seam.

To create a shear-tight connection between the connecting element and the front and rear panels of the base structure, the connecting element can be permanently attached to the front and rear panels. One-piece fastening means that the connection between the materials is so strong that the material located outside the connection will rupture before breaking or at the same time as breaking the joint under tensile stress.

The connecting element can be attached to the front and rear panels with glue. Suitable adhesives are thermoplastic hot-melt solvent-free adhesives or latex, with hot-melt solvent-free adhesives being particularly preferred. The glue can be applied in the form of a continuous coating, in the form of a pattern, such as a dot pattern or a line pattern, and in any suitable way, for example by spraying, coating with a nozzle, by printing, etc. However, other fixing methods may be used, such as heat sealing or ultrasonic welding.

The connection between the connecting element and each of the front and rear panels is made within the overlapping zone of the connecting element and the panel of the base structure. Thus, the connecting element will serve to connect the front and rear panels by attaching it to the often relatively weak elastic multilayer material in these panels by means of a connection occupying a relatively large area of about 200 mm ² to about 60,000 mm ² only shear stress, and not causing delamination forces arising in the side seams during normal use of the product. Accordingly, the connecting element serves as an element strengthening the panel material of the base structure at the lateral edges of the absorbent article, and also provides a weldable material to form a durable, preferably separable, weld side seam.

The side joints are preferably disconnectable side joints, which means that they are strong enough to withstand stresses when putting on and wearing an absorbent article such as underpants, but they can be delaminated or torn in a controlled manner when removing the article after use . Preferably, the side joints may be disconnected in the area of the welded side seams. However, it is also possible to make a connection between the connecting element and the front panel, which will lend itself to disconnection and possibly re-closure.

The connecting element is a heat sealable component. Consequently, the connecting element can be welded by any method involving heating and softening or melting the material, such as bonding using heated tools, bonding by mechanical compression with heat (bonding by pressure) or ultrasonic welding. In order for the connecting element to be thermally welded, it must contain a sufficient amount of thermoplastic material. Examples of thermoplastic polymers suitable for use in the connecting element are polyethylene, polyesters, polypropylene and other polyolefin homopolymers and copolymers and mixtures of thermoplastic polymers. The connecting element may comprise a thermoplastic film or a web of thermoplastic non-woven material, or a laminate of two or more layers of a film or non-woven material. Particularly suitable nonwoven webs are those that contain thermoplastic fibers, which are a mixture of polypropylene and polyethylene fibers. Heat-sealable nonwoven webs and films have a high content of thermoplastic material and contain at least 50% thermoplastic material and preferably at least 80% thermoplastic material.

According to a preferred embodiment of the invention, the connecting element consists of two rectangular pieces of material that are connected along a common edge, being placed so that they will be located "face to face". In this embodiment, the connecting element is a rectangular piece of material having a welded joint extending through the piece of material, preferably parallel to the side edges of the front and rear panels on the base structure, and forming a side connection on an absorbent article such as underpants.

The rectangular connecting element may have a width in the direction perpendicular to the side seam, comprising 20-200 mm The width of the connecting element determines the overlap between the connecting element and the material in the front and rear panels. For small products, such as diapers for premature babies, an overlap of 10 mm may be sufficient to provide sufficient area for a reliable connection. However, for large products intended for use by adults with severe incontinence, it may be necessary to have an overlap of up to 100 mm.

The connecting element may have a length in the direction parallel to the side seam corresponding to at least 25% of the length of the side seam. Accordingly, the connecting element can be positioned so that it will only form part of the side seam between the hole for the waist and the holes for the legs. As a rule, the connecting element can only be located along those parts of the corresponding side edges of the front and rear panels, which are made of materials having poor weldability, such as elastic laminates, which are part of the basic structure of a product such as underpants. If the pant-type absorbent article is provided with an elastic waist panel, the waist panel may include layers of a weldable material, such as an inelastic non-woven material. However, in order to take full advantage of the advantages associated with the manufacture and provided through the separate manufacture of the connecting elements and the formation of welds, the connecting elements are preferably placed so that they form side seams along their entire length. Thus, the welding operation can be performed independently of the high-speed main technological process for manufacturing a product such as underpants, and prefabricated connecting elements can be introduced into the high-speed technological process for the production of underpants, without taking into account the relatively low-speed welding operation.

An underpants type absorbent product according to the invention may be provided with an elastic waist panel that is located on at least one of the front and rear panels. The elastic waist panel may extend continuously over the entire length between the side joints and may completely surround the waist opening in the absorbent article.

The absorbent core may be a component that is included in the base structure separately or as part of a core component or “core kit” comprising a top sheet, a barrier sheet and an absorbent core located between the top sheet and the barrier sheet.

In accordance with the invention, a method is also developed for manufacturing an absorbent article such as underpants, wherein each article includes a base structure comprising a front panel having a front end edge and first and second side edges, a rear panel having a rear end edge and first and second side edges, and a crotch panel located between the front and rear panels, while the specified basic structure has a component integrated with it with an absorbing core, and the method includes otsess pant-forming comprising forming a base structure and joining the first and second front panel side edges to the respective first and second side edges of the rear panel, and combining the component with an absorbent core to the base structure.

In accordance with the invention, the process of forming underpants comprises the following additional steps:

a) the manufacture of a continuous web from preforms of connecting elements by connecting two continuous canvases of weldable material located “face to face” along paired welding lines extending in the transverse direction through a web of preforms of connecting elements;

b) cutting the web from the workpieces of the connecting elements between each two welding lines to form separate blanks of the connecting elements;

c) attaching said individual blanks of connecting elements to the base web at predetermined locations along the first edge of said base web, wherein said welding lines are located in the transverse direction of the base web;

d) bending said base web along a longitudinal fold line to align the second edge of said base web with said first edge of said base web;

f) attaching said base web to said blanks of connecting elements along said second edge of said base web;

f) cutting the specified base fabric between the specified welding lines on the specified blanks of connecting elements to separate individual products such as underpants from the specified base fabric.

The blanks of the connecting elements can be attached to the base web in step c) and / or in step e).

The method in accordance with the invention may further include any conventional manufacturing operations used in forming the underpants, such as cutting the base web to form leg openings, attaching elastic elements at the leg openings and for the waist, etc.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described hereinafter in more detail with reference to the attached drawings, in which:

figure 1 is a view of a diaper-type panties in accordance with the invention in a flat state with disconnected side connections,

figure 2 is a view of the diaper of figure 1 with closed side connections,

figure 3 is a view of the web from blanks of connecting elements,

figure 4 - view of the individual blanks of the connecting elements attached to the base fabric,

5 is a detail of the lateral connection in a product such as underpants,

6 is an alternative embodiment of the workpiece of the connecting element; and

7-9 are schematic views illustrating a method for determining the strength of the side joints in a panty type article in accordance with the present invention.

MODES FOR CARRYING OUT THE INVENTION

The panty diaper 1 shown in FIGS. 1 and 2 is intended to cover the lower part of the body of the wearer like a normal underwear. In Fig. 1, the diaper 1 is shown from the inside, that is, from the side facing the user when wearing the product, and in Fig. 2, the diaper is shown from the outside, or from the side facing the garment, which is the side facing away from the user when wearing a diaper.

The diaper 1 is shown in FIG. 1 in a flat state with the lateral joints disconnected and with all the pre-stretched elastic components in a stretched state. In Fig.2, the diaper is shown in a three-dimensional state as it will look when worn by the user.

The diaper has a front panel 2, a rear panel 3 and a crotch panel 4, extending between the front and rear panels 2, 3 and having a relatively small width compared to the front and rear panels 2, 3. The front and rear panels 2, 3 are made so that they covered the user's hips and extended over the abdomen and back of the user to cover the lower body of the user.

The diaper 1 further comprises a core zone 5 extending from the crotch panel 4 to the front panel 2 and the rear panel 3. The front and rear panels 2, 3 form that part of the base part 6, which extends from the side of the diaper 1 facing the garment and closes and surrounds core zone 5. The base part 6 includes a front panel 2, a rear panel 3, a crotch panel 4 and an elastic belt 7 attached to the front and rear panels 2, 3. Each of the front and rear panels 2, 3 has a waist edge 8 and a pair of side edges 9, respectively.

The term “panel” is used here to indicate the functional part of the base part of the diaper, while the terms “zone” and “part (section)” are used to indicate the location of a particular element of the diaper, such as the core, in the base part or to describe the intended location of a certain parts of the diaper relative to the user's body. The panel may be a separate component or part integrally with the base part. The zone or section may fully or partially include one or more panels.

When the components are connected, attached or attached to each other, they are separate parts that have been bonded by any suitable means, for example by adhesive adhesion, by stitching or by ultrasonic welding or heat welding. The term “connected” also encompasses separable connections, such as separable side connections, and re-closable connections, such as hook and loop connections, re-fastenable ribbons, button fasteners, etc. The components that were placed on top of each other need not be bonded, although in the sense used here, the term "located" should be understood in a broad sense as also encompassing bonded components.

The front and rear panels 2, 3 are connected to each other along their side edges 9 by means of side seams 10, as shown in FIG. The elastic belt 7 consists of a front waist panel 7a and a rear waist panel 7b, which are attached respectively to the front panel 2 and the rear panel 3. The front and rear waist panels 7a, 7b are also connected to each other by means of side seams 10. By connecting the front and rear panels 2, 3 and waist panels 7a, 7b diaper-pants 1 will be formed with a hole 11 for the waist and two holes 12 for the legs.

The side seams 10 are made in accordance with the invention and include a connecting element 13. The connecting element 13 contains a weldable thermoplastic material and has a first part 14, which is permanently attached along the side edge 9 from the inside of the front panel 2, and the second part 15, which permanently attached along the corresponding side edge 9 on the inner side of the rear panel 3. The first and second parts 14, 15 of each of the connecting elements 13 are connected in the side seams 10 by heat welding or ultrasound wook welding.

Figure 1 shows the diaper 1 in a flat state, with the side seams 10 disconnected and any elastic components that were attached to the base part 6 in the state when they were under tensile load extended to the full dimensions of the base part 6. Figure 2 shows the diaper-panties 1 in the form in which it looks when the side seams 10 are not touched and it was possible to relax all the stretched elastic elements and to assemble the base part into assemblies to form elastic holes 11, 12 for legs and waist.

The front and rear panels 2, 3 are preferably formed of an elastic roll material, such as an elastic laminate, comprising layers of elastic film and non-woven material. The elastic laminate may be of the type disclosed in international patent application No. WO 03/047488. A similar laminate is obtained by stepwise stretching a layer of an elastic film between two inelastic fabric-like layers. Step-by-step stretching is performed by passing a laminate between the engaged gear rollers.

The activation of elastic laminates through stepwise stretching is also disclosed in US Pat. the elasticity of the layer of elastic film.

The front and rear panels 2, 3 are preferably amenable to elastic stretching, at least in the direction of the waist edges 8, but can also be resiliently stretched in the direction perpendicular to the waist edges 8, in the direction of the side edges 9.

The elastic film in the elastic laminate is preferably perforated to impart breathability to the laminate. This can be achieved directly during the lamination process, if, for example, one or two nonwoven webs are attached to the elastic film by extrusion coating. The punching operation can be performed by passing the connected elastic layer and non-woven material over a vacuum lamination drum while the elastic layer is in a molten or semi-molten state. A similar method is disclosed in US patent No. 5733628 and leads to the fact that the elastic film is converted into a three-dimensional layer of the laminate with holes.

The crotch panel 4 is formed of crotch material 16 that has been attached to the front and rear panels 2, 3 in the crotch seams 17. Therefore, crotch material 16, which may be an inelastic material, such as an inelastic non-woven material, is located in zone 5 products provided with a core, and overlaps the elastic front and rear panels 2, 3 to a small extent. The connection can be made in any suitable way, for example by ultrasonic welding, by means of adhesive adhesion or the like. Alternatively, the outer nonwoven fabric can extend continuously along the front and rear panels 2, 3 and the crotch panel 4, so that no seams or joints 17 between the panels 4, 2, 3 are required.

In the example shown, elastic waistband 7 comprises first and second layers of a substantially inelastic nonwoven material that is elasticized by one or more elongated elastic elements 18, such as elastic threads or ribbons. The first and second layers can be formed from one layer of material that has been bent onto it itself, or can be formed from two separate strips of material. The elastic elements 18 are placed in the belt 7 in a stretched state so that they are pulled together and provide the collection of non-woven material in folds in the belt 7, when it is possible to relax, as shown in Fig.2.

The elastic belt 7 is attached to the front and rear panels 2, 3 with elastic elements 18 in a stretched state, and with the material of the front and rear panels located between the layers of non-woven material in the belt. Alternatively, the elastic waistband 7 may be a component that is prefabricated and attached to the outer side or inner side of the front and rear panels 2, 3, respectively. The waist connection 19 between the waistband 7 and the front and rear panels 2, 3 can be made in any suitable way for example by ultrasonic welding, heat sealing or by adhesive adhesion. An additional option is to form a belt 7 from one or more layers of inelastic non-woven material, which also represent parts of the front and rear panels 2, 3 and form their continuous protruding parts. It is also possible to form an elastic waist element by doubling the sections along the waist edges 8 of the elastic front and back panels 2, 3 and possibly adding additional elastic elements to the folded sections.

Elastic elements 20 are also located at the edges of the leg openings 12 and serve to give elasticity to the zones of the leg openings 12. The elastic elements at the openings 12 for the legs can be ordinary elastic elements of any type, such as elastic threads, ribbons, strips of foam material or similar elements.

The extension of the zone 5 with the core in the plane is formed by a liquid-tight barrier sheet 21 located between the absorbent core 22 and the base portion 6. The liquid-tight barrier sheet 21 has a rectangular shape, and the absorbent core 22 has an hourglass shape. A liquid-permeable topsheet 23 is located on top of the core 22 and a liquid-impermeable barrier sheet 21. Therefore, a liquid-impervious barrier sheet 21 is located below the absorbent core 22 and adjacent zones located directly outside the absorbent core 22.

The liquid-permeable topsheet 23 may consist of any material known to be used for this purpose, such as a nonwoven layer, a perforated plastic film, a mesh material, a tow or the like. The top sheet 23, of course, can also consist of a laminate of two or more sheets of the same material or different materials.

The liquid impermeable barrier sheet 21 may consist of a liquid impermeable plastic film, a sheet of nonwoven material that has been coated with a liquid barrier material, or a sheet of some other flexible material that is capable of preventing the penetration of liquids. However, it may be preferable if the liquid impermeable barrier sheet 21 is breathable, that is, allows water vapor to pass through the sheet 21.

The absorbent core 22 may be made of absorbent material, such as fluff pulverized pulp, tissue paper, absorbent foam, etc. The absorbent core may also contain superabsorbents, that is, polymeric materials that are capable of absorbing the fluid released by the body in an amount many times greater than their own weight, and form a hydrogel. Such superabsorbents are usually present in particulate form, but fibers, flakes, granules and films are also possible. In addition, the absorbent core 22 may contain non-absorbent components, such as stiffening elements, shaping elements, binders, etc. Various types of receiving fluids, porous structures, such as fiber wool, open-cell foam, or the like, may also be included in the core.

The top sheet 23, the barrier sheet 21 and the absorbent core 22 can be formed as a separate component or “core pack”, which was subsequently integrated into the base of the diaper. The various components included in the kit with the core can be connected to each other in any conventional manner, for example by adhesion adhesion, ultrasonic welding or heat sealing. Needless to say, a core kit may contain additional components besides the components described herein. The core kit may comprise, for example, a fluid transporting sheet, elastic members, shape stabilizing members, shaping members, or the like.

In addition to the components described in connection with the diaper of FIGS. 1 and 2, the panty type absorbent article according to the invention may contain any other features and elements known in the art. Examples of such additional features (elements) are means for removal in the form of strips for removal or pockets to hold the used product in a folded or folded state, various types of barriers, such as protruding, elasticated side barriers, barrier sheets along the waist edges, etc. , as well as additional fastening elements that can be used to re-fasten the product, which was opened by tearing the side seams.

Figure 3 shows a continuous web 25 of blanks of connecting elements and a blank 26 of a connecting element that was cut off from a continuous web 25. The continuous web 25 is formed by joining two continuous canvases 27, 28 face-to-face weldable material along paired welding lines 29, 30 extending in the transverse direction through the web of blanks 26 of connecting elements. In accordance with a further alternative embodiment of the invention shown in FIG. 6, the welding lines may be combined into a single welding line 40 having a width corresponding to the total width of the individual welding lines 29, 30 and a non-welded gap between the individual welding lines 29, 30 shown in figure 3. Welding lines 29, 30, 40 can be formed from separate, discrete connection points, as shown in FIGS. 3 and 6. Individual connection points can be made in the form of spots, dashed lines or other shaped elements located along lines 29, 30, 40 welding. Alternatively, the welding lines may be joints in the form of continuous lines.

The individual workpieces 26 of the connecting elements are cut off from the continuous web 25 from the workpieces of the connecting elements by cutting the web 25 between each two welding lines 29, 30 or between each wide welding line 40 or in the area of each wide welding line 40 to form separate workpieces of the connecting elements, each of which contains a group of two separate welding lines 29, 30 or one wide welding line 40.

In the embodiment shown in FIGS. 3 and 4, the continuous web 25 of the blanks of the connecting elements was made with possible connections 31 for transportation in the form of small fragile point connections located along the edges of the web 25. The connections 31 for transportation provide holding not bonded to other places of sections of layers 27, 28 on both sides of welding lines 29, 30 from separation from each other during subsequent technological operations. The transport connections 31 are preferably formed at the same time as the connections along the welding lines 29, 30 by heat bonding or ultrasonic welding.

Then, the individual blanks 26 of the connecting elements are introduced into the process of forming cowards to form an absorbent product such as cowards, and one of the layers 28 in each blank 26 of the connecting element is permanently or detachably attached to the base web 32, as shown in FIG. 4. The base web 32 is schematically shown in FIG. 4 with cutouts for the leg openings 12 and the boundaries between the individual base structures 6 shown by dashed lines 37. A core component including a core 22, a top sheet 23 and a back sheet 21 is shown as being placed between the cutouts 12 for the legs. The workpieces 26 of the connecting elements are attached in predetermined places along the first edge 33 of the base web 32, corresponding to those in which the side seams 10 will be located in the finished absorbent product such as underpants. The blanks 26 of the connecting elements are attached so that the lines 29, 30 or 40 are located in the transverse direction of the base web 32. The blanks 26 of the connecting elements can be attached to the base web 32 either before the cutouts 12 for the legs, or after the cutouts 12 for the legs on web 32. In addition, leg cutouts 12 can be formed while the web 32 is in the state shown in FIG. 4, or can be formed later in the process of forming cowards after folding the base web 32 along a longitudinal line 35 fold. If the blanks 26 of the connecting elements are attached to the base web 32 before forming the cutouts 12 for the legs, the cutouts for the legs can be partially formed on the part of the blanks 26 of the connecting elements.

The fastening is preferably provided by means of an adhesive, such as a thermoplastic hot-melt adhesive without adhesive or latex. However, it is possible to use other types of fastening, such as heat welding, ultrasonic welding or stitching. The fastening may be permanent or may be removable. The connection between the base web 32 and each workpiece 26 of the connecting element occupies a relatively large area, which provides a strong, reliable connection. During normal use of a panty-type product, the joint will only be exposed to shear stress between the material in the base web and the connecting member.

After attaching the blanks 26 of the connecting elements to the first edge of the base web 32, the base web 32 is folded along the longitudinal fold line 35 to align the second edge 34 of the base web 32 with the first edge 33 of the base web 32 and to close the blanks 26 of the connecting elements.

After that, the base fabric 32 is constantly or with the possibility of separation attached to another layer 27 of the blanks 26 of the connecting elements along the second edge 34 of the base fabric 32.

In conclusion, the folded, “bundled” base fabric 32 is cut in the transverse direction along the line 37 between the welding lines 29, 30 in the workpieces 26 of the connecting elements to separate individual items such as pants from the base fabric 32. In an embodiment in which each of the workpieces 26 the connecting elements contains one wide welding line 40, individual items such as pants are formed by cutting the fabric along the welding line 40, preferably in the center of the welding line 40, along its center line 37, as shown in Fig.6 .

It goes without saying that the technological process may include additional operations, such as applying an elastic element for a belt, applying an elastic element for legs, a barrier elastic element, etc. For absorbent articles such as underpants, the elastic element for the belt can be continuously applied to the base web in the form of a pre-formed elastic belt or in the form of continuous or intermittent elastic elements superimposed on the component representing the base at one or both edges 33, 34 of the base web 32 The elastic element for the belt can be applied to the base web 32 before joining or after joining the blanks of the connecting elements to the web.

In a finished pant-type absorbent product, each welding line 29, 30 or each part of the combined wider welding line 40 forms a side seam 10. Therefore, in accordance with the invention, a method for pre-forming side seams and incorporating pre-formed side seams into an absorbent product such as panties is proposed. This is a significant advantage in the process of forming cowards, since the welding operation is a relatively slow technological operation, which limits productivity. By manufacturing the workpieces 26 of the connecting elements separately, the workpieces 26 of the connecting elements can subsequently be introduced into the process of forming cowards at a much higher speed than would otherwise be possible. Each billet 26 of the connecting element forms two connecting elements 13, which are included in the side seams in successive absorbent products, which are cut or cut from the base fabric.

5 shows a side seam 10 with a portion of the side edge of the base structure 36 and a connecting element 13. The side seam 10 is formed by means of bonding technology, the use of which produces a joint that has a strength sufficient to withstand any stress caused by normal use an absorbent article, and which can preferably be separated by delamination or tear in a controlled manner when the article is removed from the user. By selecting a material having a high thermoplastic content, heat sealing technologies can be used for the connecting element to produce a compound having the necessary delamination resistance, but in which the delamination resistance can be adjusted to allow the connection to be disconnected manually.

The connecting element may consist of a thermoplastic film or include a thermoplastic film, but is preferably made of a web of inelastic fibrous non-woven material containing thermoplastic fibers. Examples of thermoplastic polymers suitable for use in nonwoven webs and thermoplastic films are polyethylene, polyesters, polypropylene and other polyolefin homopolymers and copolymers. Particularly suitable nonwoven webs are those that contain thermoplastic fibers, which are a mixture of polypropylene and polyethylene fibers. Weldable nonwoven webs have a high content of thermoplastic fibers and contain at least 50% thermoplastic fibers and preferably at least 80% thermoplastic fibers.

DESCRIPTION OF TEST METHODS

Elasticity test

The method allows to determine how the elastic material behaves with repeated loading and unloading cycles. The sample is stretched to a predetermined elongation and a cyclic movement from 0 to the specified predetermined elongation is performed. Target forces during loading and unloading are recorded. The residual, i.e. remaining, elongation of the material subjected to relaxation is measured.

A tensile tester, Lloyd LRX, with the ability to perform cyclic movements and equipped with a printer / plotter or software for presenting data, is used. A sample is prepared by cutting it with a width of 25 mm and a length that is preferably 20 mm greater than the distance between the clamps in the tensile testing apparatus.

The tensile tester is calibrated in accordance with the instructions for the device. The parameters required for the test (efforts under loading and unloading) are adjusted to the following values:

Slider Speed: 500mm / min

Clamp distance: 50 mm

Preload: 0.05 N

The sample is placed in the clamps in accordance with the marks and ensure that the sample is centered and fixed perpendicular to the clamps. The tensile tester is started and three cycles are performed from 0 to a predetermined elongation corresponding to the largest given first load. Before the last cycle, the sample is kept in an unstressed state for 1 minute, and then the residual elongation is measured by stretching the sample until a force of 0.1 N is determined, and the elongation is recorded.

An elastic material is defined as a material having a residual elongation after relaxation of less than 10% after subjecting the material to an elongation of 30% in the above test. Elongation of 30% means elongation to a length that is 30% more than the original length of the sample.

An inelastic material is a material that has a residual elongation after relaxation of more than 10% after subjecting the material to an elongation of 30%.

Tensile strength, side joints

The tensile strength of the lateral joints is determined in accordance with the following method (Ref: ASTM D 882 (ASTM - American Society of Testing Materials)

DEVICE:

A tensile tester connected to a computer

Slider Speed: 500 m / min

Clamp distance: 50 mm

Cutting tool or cutting tool, accuracy ± 0.1 mm

SAMPLE PREPARATION

Test samples 41 are cut from a coward type absorbent article 1, as shown in FIG. 7, in areas that are provided with a connecting element 13 in accordance with the invention. The width of the test samples 41 is 25.4 mm and the length, if possible, should be 50 mm greater than the distance between the clamps in the Instron 4301 tensile test device. Figs. 8 and 9 show how test samples 41 are secured in clamps 42.

It should be checked that the blade of the cutting device is not damaged, since it is important that the edges of the specimen are even and free from tears and incisions. Samples are incubated for at least 4 hours at a relative humidity of 50 ± 5% and a temperature of 23 ± 1 ° C before testing.

METHODOLOGY

The tensile tester is calibrated in accordance with the instructions for the device and set to zero. Prevent slipping of material by using clamps coated with galun or similar material. The specimen is fixed in the clamps and ensured that it is not secured obliquely or unevenly and the tensile testing apparatus is started. The tensile tester is started and stopped after the material ruptures (in the absence of automatic control). Test specimens that fail prematurely, for example, by rupture at the clamps or due to damage during sample preparation, should be ignored if possible.

The following results are displayed using a tensile tester / computer:

- Maximum effort, N / 25,4 mm

- Elongation at maximum effort,%

- Tearing force, N / 25.4 mm

- Relative elongation at tearing force,%

- Bend point characteristics N /%

The tensile strength of each lateral joint is recorded as the force required to break the joint.

The tensile strength of the lateral joints in the direction transverse to the side seams 10 should preferably exceed 5 N / 25.4 mm, more preferably the minimum tensile strength exceeds 10 N / 25.4 mm or 12 N / 25.4 mm and may the average is at least 15 N / 25.4 mm or 12 N / 25.4 mm, while the tensile strength of the coating materials in an absorbent article such as pants in the transverse direction preferably exceeds the tensile strength for the side joints formed in the joint element 10, and the connections between will connect an element and material in the front and back panels of the product.

Claims (22)

1. A method of manufacturing an absorbent product such as underpants, each product comprising a base structure (6) comprising a front panel (2) having a front end edge (8) and first and second side edges (9), a rear panel (3) having a rear end edge (8) and first and second side edges (9), and a crotch panel (4) located between the front and rear panels (2, 3), while the specified base structure (6) is integrated with it component (22) with an absorbent core, the method includes the process of formation of Rus, according to which they form the basic structure (6) and attach the first and second side edges (9) of the front panel (2) to the corresponding first and second side edges (9) of the rear panel (3), and combine the component (22) with an absorbent core with a basic structure (6), characterized in that in the formation of underpants:
a) a continuous web (25) is made from blanks (26) of connecting elements by joining two continuous canvases (27, 28) of the weldable material located “face to face” along the paired welding lines (29, 30) extending in the transverse direction through the web (25) from the blanks (26) of the connecting elements;
b) cutting the web (25) from the workpieces (26) of the connecting elements between each two welding lines (29, 30) to form separate blanks (26) of the connecting elements;
c) attach said individual blanks (26) of connecting elements to the base web (32) at predetermined locations along the first edge of said base web (32), wherein said welding lines (29, 30) are located in the transverse direction of the base web (32);
d) bending said base web (32) along a longitudinal fold line (35) to align the second edge (34) of said base web (32) with said first edge (33) of said base web (32);
e) attach said base web (32) to said blanks (26) of connecting elements along said second edge (34) of said base web (32);
f) cut the specified base fabric (32) between the specified lines (29, 30) of welding on the specified blanks (26) of connecting elements for separating individual products (1) type of underpants from the specified base fabric (32),
wherein said blanks (26) of connecting elements are permanently attached to said base web in steps c) and / or in step e). 2. The method according to claim 1, characterized in that the integral fastening is formed by means of glue. 3. A method of manufacturing an absorbent product such as underpants, each product comprising a base structure (6) comprising a front panel (2) having a front end edge (8) and first and second side edges (9), a rear panel (3) having a rear end edge (8) and first and second side edges (9), and a crotch panel (4) located between the front and rear panels (2, 3), while the specified base structure (6) is integrated with it component (22) with an absorbent core, and the method includes the process of formation of tr owls, according to which a basic structure (6) is formed and the first and second side edges (9) of the front panel (2) are attached to the corresponding first and second side edges (9) of the rear panel (3), and the component (22) is combined with the absorbent core with a basic structure (6), characterized in that in the formation of underpants:
a) a continuous web (25) is made from blanks (26) of connecting elements by joining two continuous canvases (27, 28), weldable material, located “face to face”, along one welding line (40), passing in the transverse direction through web (25) from blanks (26) of connecting elements;
b) cutting the web (25) from the blanks (26) of the connecting elements between each one line (40) of welding to form separate blanks (26) of the connecting elements;
c) attach said individual blanks (26) of connecting elements to the base web (32) at predetermined locations along the first edge of said base web (32), wherein said welding line (40) is located in the transverse direction of the base web (32);
d) bending said base web (32) along a longitudinal fold line (35) to align the second edge (34) of said base web (32) with said first edge (33) of said base web (32);
e) attach said base web (32) to said blanks (26) of connecting elements along said second edge (34) of said base web (32);
f) cut the specified base fabric (32) along the specified line (40) of welding on the specified blanks (26) of connecting elements for separating individual products (1) type of underpants from the specified base fabric (32),
wherein said blanks (26) of connecting elements are permanently attached to said base web in steps c) and / or in step e). 4. The method according to claim 3, characterized in that the integral fastening is formed by means of glue. 5. The method according to any one of claims 1 to 4, characterized in that the continuous web (25) of the blanks (26) of the connecting elements contains a thermoplastic film. 6. The method according to claim 5, characterized in that the continuous web (25) of the blanks (26) of the connecting elements contains at least 50% and preferably at least 80% of a thermoplastic polymer material. 7. The method according to any one of claims 1 to 4, characterized in that the continuous web (25) of the blanks (26) of the connecting elements comprises a web of thermoplastic non-woven material. 8. The method according to claim 7, characterized in that the continuous web (25) of the blanks (26) of the connecting elements contains at least 50% and preferably at least 80% of a thermoplastic polymer material. 9. An absorbent article (1) of a panty type, manufactured in accordance with the method according to any one of claims 1 to 6, containing a base structure (6), comprising a front panel (2), having a front end edge (8) and the first and second side edges (9), a rear panel (3) having a rear end edge (8) and first and second side edges (9), and a crotch panel (4) located between the front and rear panels (2, 3), while at least one of these front and rear panels (2, 3) contains an elastic laminate of nonwoven material and a film, and a core (22), integral integral with the base structure (6), while the first and second side edges (9) of the front panel (2) are connected by side seams (10) with the corresponding first and second side edges (9) of the rear panel (3), characterized in that each specified side seam (10) is formed by a heat-welded connection formed in a weldable connecting element (13), while the connecting element (13) contains the first part (27) attached to the side edge (9) on the front panel (2), and the second part (28) attached to the corresponding side edge (9) on the rear panel (3), said first and second parts (27, 28) of said connecting element (13) being connected by means of a heat-welded connection, said connecting element (13) being permanently attached to the front and back panels. 10. An absorbent article (1) of a panty type according to claim 9, characterized in that the connecting element (13) is attached to the front and rear panels (2, 3) by means of glue. 11. An absorbent article (1) of a panty type according to claim 10, characterized in that the side seams (10) are opening side seams. 12. An absorbent article (1) of a panty type according to claim 9, characterized in that the side seams (10) are opening side seams. 13. An absorbent article (1) of the type of underpants according to any one of claims 9-12, characterized in that the connecting element (13) contains a thermoplastic film. 14. An absorbent article (1) of a panty type according to any one of claims 9-12, characterized in that the connecting element (13) comprises a web of thermoplastic non-woven material. 15. An absorbent article (1) of a panty type according to any one of claims 9-12, characterized in that the connecting element (13) contains at least 50% and preferably at least 80% of a thermoplastic polymeric material. 16. An absorbent article (1) of a panty type according to any one of claims 9-12, characterized in that the connecting element (13) is a rectangular piece of material having a welded joint (29, 30) extending through a piece of material, preferably parallel to the side the edges (9) of the front and rear panels (2, 3) on the base structure (6), and forming a side seam (10) on an absorbent product (1) such as underpants. 17. An absorbent article (1) of a panty type according to claim 16, characterized in that the connecting element (13) has a width in the direction perpendicular to the side seam (10) of 20-200 mm. 18. An absorbent article (1) of a panty type according to claim 17, characterized in that the connecting element (13) has a length in the direction parallel to the side seam (10), corresponding to at least 25% of the length of the side seam (10). 19. An absorbent article (1) of a panty type according to claim 16, characterized in that the connecting element (13) has a length in the direction parallel to the side seam (10), corresponding to at least 25% of the length of the side seam (10). 20. An absorbent product (1) of a type of underpants according to any one of claims 9-12 or 17-19, characterized in that the elastic waist panel (7a, 7b) is located on at least one of the front and rear panels (2, 3). 21. An absorbent product (1) such as underpants according to claim 20, characterized in that the elastic waist panel (7a, 7b) extends continuously between the side edges (10). 22. An absorbent article (1) according to any one of claims 9-12, 17-19 or 21, characterized in that the absorbent core (22) is part of a core component comprising a top sheet (23), a barrier sheet (21) and an absorbent core (22) located between the top sheet (23) and the barrier sheet (21).

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